Two-dimensional(2D)materials have attracted tremendous interest in view of the outstanding optoelectronic properties,showing new possibilities for future photovoltaic devices toward high performance,high specific powe...Two-dimensional(2D)materials have attracted tremendous interest in view of the outstanding optoelectronic properties,showing new possibilities for future photovoltaic devices toward high performance,high specific power and flexibility.In recent years,substantial works have focused on 2D photovoltaic devices,and great progress has been achieved.Here,we present the review of recent advances in 2D photovoltaic devices,focusing on 2D-material-based Schottky junctions,homojunctions,2D−2D heterojunctions,2D−3D heterojunctions,and bulk photovoltaic effect devices.Furthermore,advanced strategies for improving the photovoltaic performances are demonstrated in detail.Finally,conclusions and outlooks are delivered,providing a guideline for the further development of 2D photovoltaic devices.展开更多
Flexible microelectronic devices have seen an increasing trend toward development of miniaturized,portable,and integrated devices as wearable electronics which have the requirement for being light weight,small in dime...Flexible microelectronic devices have seen an increasing trend toward development of miniaturized,portable,and integrated devices as wearable electronics which have the requirement for being light weight,small in dimension,and suppleness.Traditional three-dimensional(3D)and two-dimensional(2D)electronics gadgets fail to effectively comply with these necessities owing to their stiffness and large weights.Investigations have come up with a new family of one-dimensional(1D)flexible and fiber-based electronic devices(FBEDs)comprising power storage,energy-scavenging,implantable sensing,and flexible displays gadgets.However,development and manufacturing are still a challenge owing to their small radius,flexibility,low weight,weave ability and integration in textile electronics.This paper will provide a detailed review on the importance of substrates in electronic devices,intrinsic property requirements,fabrication classification and applications in energy harvesting,energy storage and other flexible electronic devices.Fiber-and textile-based electronic devices for bulk/scalable fabrications,encapsulation,and testing are reviewed and presented future research ideas to enhance the commercialization of these fiber-based electronics devices.展开更多
The enhanced performance of a squaraine compound, with 2,4-bis[4-(N,N-diisobutylamino)-2,6-dihydroxyphenyl] squaraine as the donor and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) as the acceptor, in soluti...The enhanced performance of a squaraine compound, with 2,4-bis[4-(N,N-diisobutylamino)-2,6-dihydroxyphenyl] squaraine as the donor and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) as the acceptor, in solution-processed or- ganic photovoltaic devices is obtained by using UV-ozone-treated MoO3 as the hole-collecting buffer layer. The optimized thickness of the MoO3 layer is 8 nm, at which the device shows the best power conversion efficiency (PCE) among all devices, resulting from a balance of optical absorption and charge transport. After being treated by UV-ozone for 10 min, the transmittance of the MoO3 film is almost unchanged. Atomic force microscopy results show that the treated surface morphology is improved. A high PCE of 3.99% under AM 1.5 G illumination (100 mW/cm2) is obtained.展开更多
Based on the transport equation of the semiconductor device model for 0.524 e V Ge Sn alloy and the experimental parameters of the material,the thermal-electricity conversion performance governed by a Ge Sn diode has ...Based on the transport equation of the semiconductor device model for 0.524 e V Ge Sn alloy and the experimental parameters of the material,the thermal-electricity conversion performance governed by a Ge Sn diode has been systematically studied in its normal and inverted structures.For the normal p^(+)/n(n^(+)/p)structure,it is demonstrated here that an optimal base doping N_(d(a))=3(7)×10^(18)cm^(-3) is observed,and the superior p^(+)/n structure can achieve a higher performance.To reduce material consumption,an economical active layer can comprise a 100 nm-300 nm emitter and a 3μm-6μm base to attain comparable performance to that for the optimal configuration.Our results offer many useful guidelines for the fabrication of economical Ge Sn thermophotovoltaic devices.展开更多
Due to their potentials in light‐weight,flexible,and semitransparent devices,organic photovoltaics are of great significance in the field of renewable energy.However,the narrow intrinsic absorption spectrum of organi...Due to their potentials in light‐weight,flexible,and semitransparent devices,organic photovoltaics are of great significance in the field of renewable energy.However,the narrow intrinsic absorption spectrum of organic materials hinders the full utilization of solar energy.To fabricate a highly efficient opaque solar cell,it is greatly necessary to modify the optical properties of the device to improve light absorption.In addition,the growing interest in building‐integrated photovoltaics drives the development of semitransparent devices.The preparation of semitransparent solar cells with excellent performance imposes high requirements on the high efficiency and appropriate visible light transmittance of effective optical management.In this review,the recent research progress of optical management in organic photovoltaics is reviewed,including the design of light‐absorbing materials,the modification of different layers,adding a lighttrapping structure,and changing the light absorption capabilities of specific materials,so as to provide strategies of how to improve the performance of organic photovoltaic devices and present the prospect of the area.展开更多
The blend morphology and vertical arrangement are critical to the performance of organic bulk-heterojunction photovoltaic devices.In the present paper,the authors proposed a new annealing method that controls the blen...The blend morphology and vertical arrangement are critical to the performance of organic bulk-heterojunction photovoltaic devices.In the present paper,the authors proposed a new annealing method that controls the blend morphology and vertical arrangement of two materials by means of simultaneously applying external electrical field and violet irradiation on the active layer of poly(3-hexylthiophene) (P3HT) and -phenyl C61-butyric acid methyl ester(PCBM) during annealing process.By using this annealing method,the power conversion efficiency increased by 36%,which was caused by vertical phased-separated blend of crystalline P3HT and PCBM and better charge extraction of electrodes.X-ray photoelectron spectroscopy(XPS) was measured to prove more fullerene derivatives at the organic/cathode interfaces by using this annealing method.The X-ray diffraction(XRD) analysis and UV-Vis absorption spectrum analysis also revealed more ordered polymer crystallization.展开更多
For the purpose of developing organic photovoltaic devices with good performance characteristics, we have fabricated two devices using 4T-CHO, 5T-CHO and PTCDA. The ITO/4T-CHO/PTCDA/Al device has a Voc of 2.45 V and p...For the purpose of developing organic photovoltaic devices with good performance characteristics, we have fabricated two devices using 4T-CHO, 5T-CHO and PTCDA. The ITO/4T-CHO/PTCDA/Al device has a Voc of 2.45 V and photoelectric conversion efficiency of 2.76%. The ITO/ST-CHO/PTCDA/Al device has a Voc of 2.1 3V and photoelectric conversion efficiency of 2.90%. The two devices have higher Voc (2.45 and 2.13 V). It is possible that intennolecular hydrogen bonding between -CHO group of nT-CHO and carboxylic dianhydride of PTCDA contribute to enhance the efficiency by promoting interracial electron transfer and eliminating the subconducting band trap sites.展开更多
The properties of poly(3-hexylthiophene):(6,6)-phenyl C61 butyric acid methyl ester (P3HT:PCBM) organic pho- tovoltaic devices (OPVs) with an indium tin oxide (ITO) anode treated by a KMnO4 solution are in...The properties of poly(3-hexylthiophene):(6,6)-phenyl C61 butyric acid methyl ester (P3HT:PCBM) organic pho- tovoltaic devices (OPVs) with an indium tin oxide (ITO) anode treated by a KMnO4 solution are investigated. The optimized KMnO4 solution has a concentration of 50 rag/L, and ITO is treated for 15 min. The modification of ITO anode results in an enhancement of the power conversion efficiency (PCE) of the device, which is responsible for the increase of the photocurrent. The performance enhancement is attributed to the work function modification of the ITO substrate through the strong oxygenation of KMnO4, and then the charge collection efficiency is improved.展开更多
For the purpose of developing flexible organic photovoltaic devices, we have fabricated two flexible devices using 5-formyl- 2,2′:5′,2″:5″,2′″-quaterthiophene (4T-CHO), 5-formyl-2,2′:5′, 2″:5″,2′″:...For the purpose of developing flexible organic photovoltaic devices, we have fabricated two flexible devices using 5-formyl- 2,2′:5′,2″:5″,2′″-quaterthiophene (4T-CHO), 5-formyl-2,2′:5′, 2″:5″,2′″:5′″,2″″-quinquethiophene (5T-CHO) and 3,4,9,10-perylenetertracarboxylic dianhydride (PTCDA). The PET-ITO/4T-CHO/PTCDA/A1 device has an open circuit voltage (Voc) of 1.56 V, photoelectric conversion efficiency of 0.77%. The PET-ITO/5T-CHO/PTCDA/A1 device has a Voc of 1.70 V, photoelectric conversion efficiency of 0.84%. The two flexible devices have high Voc (1.56 and 1.70 V). It is possible that intermolecular hydrogen bonding between -CHO group of nT-CHO and carboxylic dianhydride of PTCDA contributes to enhancing the efficiency by promoting interfacial electron transfer and eliminating the subconducting band trap sites.展开更多
Perovskite-type photovoltaic devices with polysilane hole transport layers were fabricated by a spin-coating method. In the present work, poly(methyl phenylsilane) (PMPS) and decaphenylcyclopentasilane (DPPS) were use...Perovskite-type photovoltaic devices with polysilane hole transport layers were fabricated by a spin-coating method. In the present work, poly(methyl phenylsilane) (PMPS) and decaphenylcyclopentasilane (DPPS) were used as the hole transport layers. First, structural and optical properties of the PMPS and DPPS films were investigated, and the as-prepared PMPS and DPPS films were amorphous. Optical absorption spectra of the amorphous PMPS and DPPS showed some marked features due to the nature of polysilanes. Then, microstructures, optical and photovoltaic properties of the perovskite-type photovoltaic devices with polysilane hole transport layers were investigated. Current density-voltage characteristics and incident photon to current conversion efficiency of the photovoltaic devices with the polysilane layers showed different photovoltaic performance each other, attributed to molecular structures of the polysilanes and Si content in the present hole transport layers.展开更多
To better utilize the infrared(IR)region in sunlight for photovoltaic devices(PVs),upconversion nanoparticles(UCNPs)have been proposed to improve power conversion efficiency(PCE).However,researchers recently have foun...To better utilize the infrared(IR)region in sunlight for photovoltaic devices(PVs),upconversion nanoparticles(UCNPs)have been proposed to improve power conversion efficiency(PCE).However,researchers recently have found that the upconversion(UC)effect is negligible in PVs performance improvement for their ultra-low UC photoluminescence quantum yields of UCNPs solid film,while the real mechanism of UCNPs in PVs has not been clearly studied.Herein,based on the material inorganic perovskitesγ-CsPbI_(3),NaYF_(4):20%Yb^(3+),2%Er^(3+)UCNPs were integrated into different transport layer to optimize device performance.Compared with reference device,the short-circuit current density and PCE of optimized device reached 20.87 mA/cm^(2)(20.39 mA/cm^(2))and 18.34%(17.72%),respectively,without sacrificing open-circuit voltage and filling factor.Further experimental characterizations verified that the improved performance was attributable to enhanced visible light absorption instead of IR.To theoretically explain the statement,the light field distribution in device was simulated and the absorption in different layers was calculated.The results revealed that the introduction of UCNPs with different refractive index from other layers caused light field disturbance,and improved visible light captured by γ-CsPbI_(3).Importantly,through experiments and theoretical calculation,the research deeply explored the potential mechanism of UCNPs in optimizing PVs performance.展开更多
Over the past decade,perovskite photovoltaics have approached other currently available technologies and proven to be the most prospective type of solar cells.Although the many-sided research in this very active field...Over the past decade,perovskite photovoltaics have approached other currently available technologies and proven to be the most prospective type of solar cells.Although the many-sided research in this very active field has generated consistent results with regard to their undisputed consistently increasing power conversion efficiency,it also produced several rather contradictory opinions.Among other important details,debate surrounding their proneness to surface degradation and poor mechanical robustness,as well as the environmental footprint of this materials class,remains a moot point.The application of ionic liquids appears as one of the potential remedies to some of these challenges due to their high conductivity,the opportunities for chemical"tuning"of the structure,and relatively lower environmental footprint.This article provides an overview,classification,and applications of ionic liquids in perovskite solar cells.We summarize the use and role of ionic liquids as versatile additives,solvents,and modifiers in perovskite precursor solution,in charge transport layer,and in interfacial and stability engineering.Finally,challenges and the future prospects for the design and/or selection of ionic liquids with a specific profile that meets the requirements for next-generation highly efficient and stable perovskite solar cells are proposed.展开更多
Thin films and thin film devices have a ubiquitous presence in numerous conventional and emerging technologies. This is because of the recent advances in nanotechnology, the development of functional and smart materia...Thin films and thin film devices have a ubiquitous presence in numerous conventional and emerging technologies. This is because of the recent advances in nanotechnology, the development of functional and smart materials,conducting polymers, molecular semiconductors, carbon nanotubes, and graphene, and the employment of unique properties of thin films and ultrathin films, such as high surface area, controlled nanostructure for effective charge transfer, and special physical and chemical properties, to develop new thin film devices. This paper is therefore intended to provide a concise critical review and research directions on most thin film devices, including thin film transistors, data storage memory, solar cells, organic light-emitting diodes, thermoelectric devices, smart materials, sensors, and actuators. The thin film devices may consist of organic, inorganic, and composite thin layers, and share similar functionality, properties, and fabrication routes. Therefore, due to the multidisciplinary nature of thin film devices, knowledge and advances already made in one area may be applicable to other similar areas. Owing to the importance of developing low-cost, scalable, and vacuum-free fabrication routes, this paper focuses on thin film devices that may be processed and deposited from solution.展开更多
A new europium(Ⅲ) complex, tris(dibertzoylmethanate){ 1-[9-hexyl-9-carbazole]-2-(2-pyridyl)-bertzimidazole}europium(Ⅲ) [Eu(DBM)a(CPyBM)] was synthesized and used as an electron-acceptor and electron-tran...A new europium(Ⅲ) complex, tris(dibertzoylmethanate){ 1-[9-hexyl-9-carbazole]-2-(2-pyridyl)-bertzimidazole}europium(Ⅲ) [Eu(DBM)a(CPyBM)] was synthesized and used as an electron-acceptor and electron-transport layer in organic photovoltaic (PV) device. Power conversion efficiency achieved from the device was 1.04% under illumination with 365 nm UV light at 1.6 mW/cm^2. Compared with the previous reported devices based on Eu(Ⅲ) complexes, the PV performances were improved. The working mechanism of the organic PV device was discussed.展开更多
The ITO/5T/PCH/Al1 device has a short circuit current of 3.4 mA/cm^2, an open circuit voltage of 2.1 V, fill fact of 27.5 % and photoelectric conversion efficiency of 2.5 %.
Excellent electrical properties and the impact of latest power devices for improving the efficiency of photovohaic(PV) inverters are presented.Power modules using SiC-MOSFET and SBD exhibit the possibility to realiz...Excellent electrical properties and the impact of latest power devices for improving the efficiency of photovohaic(PV) inverters are presented.Power modules using SiC-MOSFET and SBD exhibit the possibility to realize PV inverters with peak efficiency beyond 99%.Si-IGBT modules using reverse-blocking(RB)-IGBT have enabled to massproduce PV inverters with peak efficiency of 98.4%.Si superjunction(SJ)-MOSFET and discrete IGBT have enabled to improve the efficiency of small power PV inverters by 0.5 point.展开更多
The porphyrin derivatives, 5,10,15,20-tetra(4-(N-pentane-carboxamide) phenyl) porphyrin(4 NC5-TPP), 5,10,15,20-tetra(4-(N-dodecane-carboxamide) phenyl) porphyrin(4 NC12-TPP) and their zinc-complexes(4 NC5...The porphyrin derivatives, 5,10,15,20-tetra(4-(N-pentane-carboxamide) phenyl) porphyrin(4 NC5-TPP), 5,10,15,20-tetra(4-(N-dodecane-carboxamide) phenyl) porphyrin(4 NC12-TPP) and their zinc-complexes(4 NC5-TPPZn and 4 NC12-TPPZn), have been synthesized. Their thermal properties and morphologies were investigated via thermal gravity analysis(TGA), differential scanning calorimetry(DSC) and polarized optical microscopy(POM). It was found that the 4 NC5-TPP was amorphous and the 4 NC5-TPPZn was crystalline at room temperature, while the 4 NC12-TPP formed the columnar liquid crystal and the 4 NC12-TPPZn showed the spherulite texture. The electron state density distributions and the optimum configuration of the porphyrin derivatives were calculated by chemical simulation. The electrochemical oxidation and reduction abilities of the porphyrin derivatives were studied by cyclic voltammetry(CV). It was indicated that the porphyrin derivatives had the potential to develop organic photovoltaic(OPV) devices. Using the porphyrin derivatives as donor materials and the 3,4,9,10-perylenetetracarboxylic dianhydride(PTCDA) as the acceptor material, the OPV devices were fabricated. The device structure is ITO/porphyrin derivatives:PTCDA/Al. The relationship between the morphology and performance of OPV was studied. It was found that the crystalline morphology of the film was beneficial to improve the efficiency of the devices.展开更多
This paper mainly studies scheduling type photovoltaic generation system, and establishes a three-phase photovoltaic grid-connected model in Matlab/Simulink, which uses the MPPT control that can make full use of the s...This paper mainly studies scheduling type photovoltaic generation system, and establishes a three-phase photovoltaic grid-connected model in Matlab/Simulink, which uses the MPPT control that can make full use of the solar energy. At the same time, energy storage device is added. The inverter of the energy storage device adopts V/f control. In the running state of the islanding because of a certain power failure, it can maintain a constant voltage and frequency. The simulation shows that as the output of the photovoltaic power increases, harmonic rate decreases under the same conditions, and the energy storage device can increase the stability of photovoltaic grid and reduce harmonic contents. So it’s very necessary to add energy storage device in the photovoltaic system.展开更多
100-W class power storage systems were developed, which comprised spherical Si solar cells, a maximum power point tracking charge control-ler, a lithium-ion battery, and one of two different types of direct current (D...100-W class power storage systems were developed, which comprised spherical Si solar cells, a maximum power point tracking charge control-ler, a lithium-ion battery, and one of two different types of direct current (DC)-alter- nating current (AC) converters. One inverter used SiC met-al-oxide-semicon-ductor field-effect transistors (MOSFETs) as switching devices while the other used Si MOSFETs. In these 100-W class inverters, the ON resistance was considered to have little influence on the efficiency. Nevertheless, the SiC-based inverter exhibited an approximately 3% higher DC-AC conversion efficiency than the Si-based inverter. Power loss analysis indicated that the higher efficiency resulted predominantly from lower switching and reverse recovery losses in the SiC MOSFETs compared with in the Si MOSFETs.展开更多
To study the efficiency increasing of electric energy generation in the Photovoltaic System is concentrated on this paper. There are four cases to improve the efficiency of power producing from the Photovoltaic System...To study the efficiency increasing of electric energy generation in the Photovoltaic System is concentrated on this paper. There are four cases to improve the efficiency of power producing from the Photovoltaic System. This article not only describes the differences of facilities before and after the proposal, but also evaluates the electric energy generation efficiency and improved results for each proposal. Finally, the better efficiency of all improving ways is analyzed to get into conclusions in order to provide further improvement and reference for the industry in the future. Overall, these proposed methods can improve the efficiency of solar photovoltaic electric energy generation in about 30.18%.展开更多
基金supported by the National Natural Science Foundation of China(52322210,52172144,22375069,21825103,and U21A2069)National Key R&D Program of China(2021YFA1200501)+1 种基金Shenzhen Science and Technology Program(JCYJ20220818102215033,JCYJ20200109105422876)the Innovation Project of Optics Valley Laboratory(OVL2023PY007).
文摘Two-dimensional(2D)materials have attracted tremendous interest in view of the outstanding optoelectronic properties,showing new possibilities for future photovoltaic devices toward high performance,high specific power and flexibility.In recent years,substantial works have focused on 2D photovoltaic devices,and great progress has been achieved.Here,we present the review of recent advances in 2D photovoltaic devices,focusing on 2D-material-based Schottky junctions,homojunctions,2D−2D heterojunctions,2D−3D heterojunctions,and bulk photovoltaic effect devices.Furthermore,advanced strategies for improving the photovoltaic performances are demonstrated in detail.Finally,conclusions and outlooks are delivered,providing a guideline for the further development of 2D photovoltaic devices.
基金National Funds through FCT–Portuguese Foundation for Science and Technology under the projects PTDC/CTM-CTM/1571/2020(All-Fi BRE),LA/P/0037/2020,UIDP/50025/2020 and UIDB/50025/2020(CENIMAT/I3N)by ERC-Co G-2014,CapTherPV,647596。
文摘Flexible microelectronic devices have seen an increasing trend toward development of miniaturized,portable,and integrated devices as wearable electronics which have the requirement for being light weight,small in dimension,and suppleness.Traditional three-dimensional(3D)and two-dimensional(2D)electronics gadgets fail to effectively comply with these necessities owing to their stiffness and large weights.Investigations have come up with a new family of one-dimensional(1D)flexible and fiber-based electronic devices(FBEDs)comprising power storage,energy-scavenging,implantable sensing,and flexible displays gadgets.However,development and manufacturing are still a challenge owing to their small radius,flexibility,low weight,weave ability and integration in textile electronics.This paper will provide a detailed review on the importance of substrates in electronic devices,intrinsic property requirements,fabrication classification and applications in energy harvesting,energy storage and other flexible electronic devices.Fiber-and textile-based electronic devices for bulk/scalable fabrications,encapsulation,and testing are reviewed and presented future research ideas to enhance the commercialization of these fiber-based electronics devices.
基金Project supported by the Program for New Century Excellent Talents in University of Ministry of Education of China(Grant No.NCET-10-0220)the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20120009130005)the Fundamental Research Funds for the Central Universities of Ministry of Education of China(Grant No.2012JBZ001)
文摘The enhanced performance of a squaraine compound, with 2,4-bis[4-(N,N-diisobutylamino)-2,6-dihydroxyphenyl] squaraine as the donor and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) as the acceptor, in solution-processed or- ganic photovoltaic devices is obtained by using UV-ozone-treated MoO3 as the hole-collecting buffer layer. The optimized thickness of the MoO3 layer is 8 nm, at which the device shows the best power conversion efficiency (PCE) among all devices, resulting from a balance of optical absorption and charge transport. After being treated by UV-ozone for 10 min, the transmittance of the MoO3 film is almost unchanged. Atomic force microscopy results show that the treated surface morphology is improved. A high PCE of 3.99% under AM 1.5 G illumination (100 mW/cm2) is obtained.
基金Project supported by the Beijing Natural Science Foundation Program,China(Grant No.4192016)。
文摘Based on the transport equation of the semiconductor device model for 0.524 e V Ge Sn alloy and the experimental parameters of the material,the thermal-electricity conversion performance governed by a Ge Sn diode has been systematically studied in its normal and inverted structures.For the normal p^(+)/n(n^(+)/p)structure,it is demonstrated here that an optimal base doping N_(d(a))=3(7)×10^(18)cm^(-3) is observed,and the superior p^(+)/n structure can achieve a higher performance.To reduce material consumption,an economical active layer can comprise a 100 nm-300 nm emitter and a 3μm-6μm base to attain comparable performance to that for the optimal configuration.Our results offer many useful guidelines for the fabrication of economical Ge Sn thermophotovoltaic devices.
基金This study was mostly supported by the National Key Researchand Development Program of China(Grant No.2017YFA0206600)the Key Research Program of FrontierScience,Chinese Academy of Sciences(Grant No.QYZDBSSW‐SLH006)+5 种基金the National Natural Science Foundation ofChina(Contract No.61674141,51972300,62011530022,and 21975245)the Strategic Priority Research Program ofChinese Academy of Sciences(Grant No.XDB43000000)Prof.Zhijie Wang appreciates support from the Hundred Talents Program(Chinese Academy of Sciences)Kong Liualso acknowledges the support from the Youth InnovationPromotion Associationthe Chinese Academy of Sciences(No.2020114)the NOVA of Beijing Science andTechnology(No.2020117).
文摘Due to their potentials in light‐weight,flexible,and semitransparent devices,organic photovoltaics are of great significance in the field of renewable energy.However,the narrow intrinsic absorption spectrum of organic materials hinders the full utilization of solar energy.To fabricate a highly efficient opaque solar cell,it is greatly necessary to modify the optical properties of the device to improve light absorption.In addition,the growing interest in building‐integrated photovoltaics drives the development of semitransparent devices.The preparation of semitransparent solar cells with excellent performance imposes high requirements on the high efficiency and appropriate visible light transmittance of effective optical management.In this review,the recent research progress of optical management in organic photovoltaics is reviewed,including the design of light‐absorbing materials,the modification of different layers,adding a lighttrapping structure,and changing the light absorption capabilities of specific materials,so as to provide strategies of how to improve the performance of organic photovoltaic devices and present the prospect of the area.
基金supported by the National Natural Science Foundation of China under grant No.10934001the National Basic Research Program of China under grant No.2009CB930504
文摘The blend morphology and vertical arrangement are critical to the performance of organic bulk-heterojunction photovoltaic devices.In the present paper,the authors proposed a new annealing method that controls the blend morphology and vertical arrangement of two materials by means of simultaneously applying external electrical field and violet irradiation on the active layer of poly(3-hexylthiophene) (P3HT) and -phenyl C61-butyric acid methyl ester(PCBM) during annealing process.By using this annealing method,the power conversion efficiency increased by 36%,which was caused by vertical phased-separated blend of crystalline P3HT and PCBM and better charge extraction of electrodes.X-ray photoelectron spectroscopy(XPS) was measured to prove more fullerene derivatives at the organic/cathode interfaces by using this annealing method.The X-ray diffraction(XRD) analysis and UV-Vis absorption spectrum analysis also revealed more ordered polymer crystallization.
基金the Ministry of Science and Technology of China (National Key Program for Basic Research, No. 2001-CCA03500) NNSFC (Nos. 20674022 and 20534020)+1 种基金Science Foundation of Guangdong (Nos. 04105931 and 2006A10702003) Guangzhou (No. 2004J1-C0041) for financial support.
文摘For the purpose of developing organic photovoltaic devices with good performance characteristics, we have fabricated two devices using 4T-CHO, 5T-CHO and PTCDA. The ITO/4T-CHO/PTCDA/Al device has a Voc of 2.45 V and photoelectric conversion efficiency of 2.76%. The ITO/ST-CHO/PTCDA/Al device has a Voc of 2.1 3V and photoelectric conversion efficiency of 2.90%. The two devices have higher Voc (2.45 and 2.13 V). It is possible that intennolecular hydrogen bonding between -CHO group of nT-CHO and carboxylic dianhydride of PTCDA contribute to enhance the efficiency by promoting interracial electron transfer and eliminating the subconducting band trap sites.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.10974013 and 60978060)the Research Fund for the Doctoral Program of Higher Education,China(Grant No.20090009110027)+3 种基金the Beijing Municipal Natural Science Foundation,China(Grant No.1102028)the New Century Excellent Talents in University,China(Grant No.NCET-10-0220)the Fundamental Research Funds for the Central Universities,China(Grant No.2012JBZ001)the Technology Innovation Fund for Outstanding Ph.D.Students of Beijing Jiaotong University,China(Grant No.48034)
文摘The properties of poly(3-hexylthiophene):(6,6)-phenyl C61 butyric acid methyl ester (P3HT:PCBM) organic pho- tovoltaic devices (OPVs) with an indium tin oxide (ITO) anode treated by a KMnO4 solution are investigated. The optimized KMnO4 solution has a concentration of 50 rag/L, and ITO is treated for 15 min. The modification of ITO anode results in an enhancement of the power conversion efficiency (PCE) of the device, which is responsible for the increase of the photocurrent. The performance enhancement is attributed to the work function modification of the ITO substrate through the strong oxygenation of KMnO4, and then the charge collection efficiency is improved.
基金supported by the Ministry of Science and Technology of China(National Key Program for Basic Research,No.2001-CCA03500)NSFC(Nos.20674022,20534020,and 20774031)+1 种基金the Natural Science Foundation of Guangdong(Nos.04105931 and 2006A10702003)Guangzhou(No.2004J1-C0041)for financial support.
文摘For the purpose of developing flexible organic photovoltaic devices, we have fabricated two flexible devices using 5-formyl- 2,2′:5′,2″:5″,2′″-quaterthiophene (4T-CHO), 5-formyl-2,2′:5′, 2″:5″,2′″:5′″,2″″-quinquethiophene (5T-CHO) and 3,4,9,10-perylenetertracarboxylic dianhydride (PTCDA). The PET-ITO/4T-CHO/PTCDA/A1 device has an open circuit voltage (Voc) of 1.56 V, photoelectric conversion efficiency of 0.77%. The PET-ITO/5T-CHO/PTCDA/A1 device has a Voc of 1.70 V, photoelectric conversion efficiency of 0.84%. The two flexible devices have high Voc (1.56 and 1.70 V). It is possible that intermolecular hydrogen bonding between -CHO group of nT-CHO and carboxylic dianhydride of PTCDA contributes to enhancing the efficiency by promoting interfacial electron transfer and eliminating the subconducting band trap sites.
文摘Perovskite-type photovoltaic devices with polysilane hole transport layers were fabricated by a spin-coating method. In the present work, poly(methyl phenylsilane) (PMPS) and decaphenylcyclopentasilane (DPPS) were used as the hole transport layers. First, structural and optical properties of the PMPS and DPPS films were investigated, and the as-prepared PMPS and DPPS films were amorphous. Optical absorption spectra of the amorphous PMPS and DPPS showed some marked features due to the nature of polysilanes. Then, microstructures, optical and photovoltaic properties of the perovskite-type photovoltaic devices with polysilane hole transport layers were investigated. Current density-voltage characteristics and incident photon to current conversion efficiency of the photovoltaic devices with the polysilane layers showed different photovoltaic performance each other, attributed to molecular structures of the polysilanes and Si content in the present hole transport layers.
基金funded by the National Natural Science Foundation of China(52073131,51902148,61874166,51802024,11974069 and U1832149)the Fundamental Research Funds for the Central Universities(lzujbky-2020-61,lzujbky-2020-64,lzujbky-2021-it31,lzujbky-2021-ct15 and lzujbky-2021-ct01)+2 种基金the Natural Science Foundation of Gansu Province(20JR5RA278 and 20JR5RA24)the LiaoNing Revitalization Talents Program(XLYC1902113)the Science and Technology Program of Qinghai Province(2020-HZ-809)。
文摘To better utilize the infrared(IR)region in sunlight for photovoltaic devices(PVs),upconversion nanoparticles(UCNPs)have been proposed to improve power conversion efficiency(PCE).However,researchers recently have found that the upconversion(UC)effect is negligible in PVs performance improvement for their ultra-low UC photoluminescence quantum yields of UCNPs solid film,while the real mechanism of UCNPs in PVs has not been clearly studied.Herein,based on the material inorganic perovskitesγ-CsPbI_(3),NaYF_(4):20%Yb^(3+),2%Er^(3+)UCNPs were integrated into different transport layer to optimize device performance.Compared with reference device,the short-circuit current density and PCE of optimized device reached 20.87 mA/cm^(2)(20.39 mA/cm^(2))and 18.34%(17.72%),respectively,without sacrificing open-circuit voltage and filling factor.Further experimental characterizations verified that the improved performance was attributable to enhanced visible light absorption instead of IR.To theoretically explain the statement,the light field distribution in device was simulated and the absorption in different layers was calculated.The results revealed that the introduction of UCNPs with different refractive index from other layers caused light field disturbance,and improved visible light captured by γ-CsPbI_(3).Importantly,through experiments and theoretical calculation,the research deeply explored the potential mechanism of UCNPs in optimizing PVs performance.
基金support from the National Natural Science Foundation of China(62004129,22005202)is gratefully acknowledgedNew York University Abu Dhabi for financial support.
文摘Over the past decade,perovskite photovoltaics have approached other currently available technologies and proven to be the most prospective type of solar cells.Although the many-sided research in this very active field has generated consistent results with regard to their undisputed consistently increasing power conversion efficiency,it also produced several rather contradictory opinions.Among other important details,debate surrounding their proneness to surface degradation and poor mechanical robustness,as well as the environmental footprint of this materials class,remains a moot point.The application of ionic liquids appears as one of the potential remedies to some of these challenges due to their high conductivity,the opportunities for chemical"tuning"of the structure,and relatively lower environmental footprint.This article provides an overview,classification,and applications of ionic liquids in perovskite solar cells.We summarize the use and role of ionic liquids as versatile additives,solvents,and modifiers in perovskite precursor solution,in charge transport layer,and in interfacial and stability engineering.Finally,challenges and the future prospects for the design and/or selection of ionic liquids with a specific profile that meets the requirements for next-generation highly efficient and stable perovskite solar cells are proposed.
基金Research funding from the Shanghai Municipal Education Commission in the framework of the oriental scholar and distinguished professor designationfunding from the National Natural Science Foundation of China(NSFC)
文摘Thin films and thin film devices have a ubiquitous presence in numerous conventional and emerging technologies. This is because of the recent advances in nanotechnology, the development of functional and smart materials,conducting polymers, molecular semiconductors, carbon nanotubes, and graphene, and the employment of unique properties of thin films and ultrathin films, such as high surface area, controlled nanostructure for effective charge transfer, and special physical and chemical properties, to develop new thin film devices. This paper is therefore intended to provide a concise critical review and research directions on most thin film devices, including thin film transistors, data storage memory, solar cells, organic light-emitting diodes, thermoelectric devices, smart materials, sensors, and actuators. The thin film devices may consist of organic, inorganic, and composite thin layers, and share similar functionality, properties, and fabrication routes. Therefore, due to the multidisciplinary nature of thin film devices, knowledge and advances already made in one area may be applicable to other similar areas. Owing to the importance of developing low-cost, scalable, and vacuum-free fabrication routes, this paper focuses on thin film devices that may be processed and deposited from solution.
基金The authors gratefully thank the financial supports of 0ne Hundred Talents Project from Chinese Academy of Sciencesthe National Natural Science Foundations of China(No.20571071).
文摘A new europium(Ⅲ) complex, tris(dibertzoylmethanate){ 1-[9-hexyl-9-carbazole]-2-(2-pyridyl)-bertzimidazole}europium(Ⅲ) [Eu(DBM)a(CPyBM)] was synthesized and used as an electron-acceptor and electron-transport layer in organic photovoltaic (PV) device. Power conversion efficiency achieved from the device was 1.04% under illumination with 365 nm UV light at 1.6 mW/cm^2. Compared with the previous reported devices based on Eu(Ⅲ) complexes, the PV performances were improved. The working mechanism of the organic PV device was discussed.
基金Ministry of Education of the People's Republic of China (Research Funds for Chinese Scholars Returning from Abroad) the Ministry of Science and Technology of the People's Republic of China (National Key Program for Basic Research, 2001-CCA03500)+1 种基金 the Natural Science Foundation of Guangdong (No. 04105931) Guangzhou for financial support.
文摘The ITO/5T/PCH/Al1 device has a short circuit current of 3.4 mA/cm^2, an open circuit voltage of 2.1 V, fill fact of 27.5 % and photoelectric conversion efficiency of 2.5 %.
文摘Excellent electrical properties and the impact of latest power devices for improving the efficiency of photovohaic(PV) inverters are presented.Power modules using SiC-MOSFET and SBD exhibit the possibility to realize PV inverters with peak efficiency beyond 99%.Si-IGBT modules using reverse-blocking(RB)-IGBT have enabled to massproduce PV inverters with peak efficiency of 98.4%.Si superjunction(SJ)-MOSFET and discrete IGBT have enabled to improve the efficiency of small power PV inverters by 0.5 point.
基金Funded by the National Natural Science Foundation of China(Nos.20674022,20774031,21074039)the Natural Science Foundation of Guangdong(Nos.2006A10702003,2009B090300025,2010A090100001,2014A030313241,2014B090901068,2016A010103003)+1 种基金the Science and Technology Program of Guangdong and GuangzhouThe Ministry of Education of the People’s Republic of China(No.20090172110011)
文摘The porphyrin derivatives, 5,10,15,20-tetra(4-(N-pentane-carboxamide) phenyl) porphyrin(4 NC5-TPP), 5,10,15,20-tetra(4-(N-dodecane-carboxamide) phenyl) porphyrin(4 NC12-TPP) and their zinc-complexes(4 NC5-TPPZn and 4 NC12-TPPZn), have been synthesized. Their thermal properties and morphologies were investigated via thermal gravity analysis(TGA), differential scanning calorimetry(DSC) and polarized optical microscopy(POM). It was found that the 4 NC5-TPP was amorphous and the 4 NC5-TPPZn was crystalline at room temperature, while the 4 NC12-TPP formed the columnar liquid crystal and the 4 NC12-TPPZn showed the spherulite texture. The electron state density distributions and the optimum configuration of the porphyrin derivatives were calculated by chemical simulation. The electrochemical oxidation and reduction abilities of the porphyrin derivatives were studied by cyclic voltammetry(CV). It was indicated that the porphyrin derivatives had the potential to develop organic photovoltaic(OPV) devices. Using the porphyrin derivatives as donor materials and the 3,4,9,10-perylenetetracarboxylic dianhydride(PTCDA) as the acceptor material, the OPV devices were fabricated. The device structure is ITO/porphyrin derivatives:PTCDA/Al. The relationship between the morphology and performance of OPV was studied. It was found that the crystalline morphology of the film was beneficial to improve the efficiency of the devices.
文摘This paper mainly studies scheduling type photovoltaic generation system, and establishes a three-phase photovoltaic grid-connected model in Matlab/Simulink, which uses the MPPT control that can make full use of the solar energy. At the same time, energy storage device is added. The inverter of the energy storage device adopts V/f control. In the running state of the islanding because of a certain power failure, it can maintain a constant voltage and frequency. The simulation shows that as the output of the photovoltaic power increases, harmonic rate decreases under the same conditions, and the energy storage device can increase the stability of photovoltaic grid and reduce harmonic contents. So it’s very necessary to add energy storage device in the photovoltaic system.
文摘100-W class power storage systems were developed, which comprised spherical Si solar cells, a maximum power point tracking charge control-ler, a lithium-ion battery, and one of two different types of direct current (DC)-alter- nating current (AC) converters. One inverter used SiC met-al-oxide-semicon-ductor field-effect transistors (MOSFETs) as switching devices while the other used Si MOSFETs. In these 100-W class inverters, the ON resistance was considered to have little influence on the efficiency. Nevertheless, the SiC-based inverter exhibited an approximately 3% higher DC-AC conversion efficiency than the Si-based inverter. Power loss analysis indicated that the higher efficiency resulted predominantly from lower switching and reverse recovery losses in the SiC MOSFETs compared with in the Si MOSFETs.
文摘To study the efficiency increasing of electric energy generation in the Photovoltaic System is concentrated on this paper. There are four cases to improve the efficiency of power producing from the Photovoltaic System. This article not only describes the differences of facilities before and after the proposal, but also evaluates the electric energy generation efficiency and improved results for each proposal. Finally, the better efficiency of all improving ways is analyzed to get into conclusions in order to provide further improvement and reference for the industry in the future. Overall, these proposed methods can improve the efficiency of solar photovoltaic electric energy generation in about 30.18%.