We develop the effective modification strategy based on molecular engineering of s-triazine and its derivatives to improve the photoelectric performance of all-inorganic perovskites(AIP)for the first time.The surface ...We develop the effective modification strategy based on molecular engineering of s-triazine and its derivatives to improve the photoelectric performance of all-inorganic perovskites(AIP)for the first time.The surface modification strategy with cyanuric acid successfully increases the PLQY of AIP from 40.55%to 88.15%,and significantly enhances the current of the AIP film under 3 V by almost 20-fold(from4.44 m A to 81.20 m A).This work has proven the effectiveness of improving the photoelectric performances of AIP via s-triazine and its derivatives and also suggested the potential risks of reducing the photoelectric performance of AIP due to inappropriate substituents in conjugated organic ligands.展开更多
A design of an inverse U-shape buried doping in a pinned photodiode (PPD) of CMOS image sensors is proposed for electrical crosstalk suppression between adjacent pixels. The architecture achieves no extra fill facto...A design of an inverse U-shape buried doping in a pinned photodiode (PPD) of CMOS image sensors is proposed for electrical crosstalk suppression between adjacent pixels. The architecture achieves no extra fill factor consumption, and proper built-in electric fields can be established according to the doping gradient created by the injections of the extremely low P-type doping buried regions in the epitaxial layer, causing the excess electrons to easily drift back to the photosensitive area rarely with a diffusion probability; the overall junction capacitance and photosensitive area extensions for a full well capacity (FWC) and internal quantum efficiency (IQE) improving are achieved by the injection of a buried N-type doping. By considering the image lag issue, the process parameters of all the injections have been precisely optimized. Optical simulation results based on the finite difference time domain method show that compared to the conventional PPD, the electrical crosstalk rate of the proposed architecture can be decreased by 60%-80% at an incident wavelength beyond 450 nm, IQE can be clearly improved at an incident wavelength between 400 and 600 nm, and the FWC can be enhanced by 107.5%. Furthermore, the image lag performance is sustained to a perfect low level. The present study provides important guidance on the design of ultra high resolution image sensors.展开更多
Near-infrared organic photodiodes (NIR OPDs) have tremendous potential in industrial, military, and scientific applications, due to their unique features of lightweight, low toxicity, high structural flexibility, cool...Near-infrared organic photodiodes (NIR OPDs) have tremendous potential in industrial, military, and scientific applications, due to their unique features of lightweight, low toxicity, high structural flexibility, cooling-system-free, etc. However, the overall performance of currently available NIR OPDs still lags behind the commercial inorganic photodetectors, ascribed to the critical challenge of realizing organic semiconductors with sufficiently low optical bandgap and excellent optoelectronic properties simultaneously. Among various types of NIR-absorbing organic semiconductors, polymethine dyes not only possess advantages of simple synthesis and structural diversity, but also show fascinating optical and aggregation features in the solid state, making them attractive material candidates for NIR OPDs. In this review, after a brief introduction of NIR OPDs and polymethine dyes, we comprehensively summarize the advances of polymethine dyes for broadband and narrowband NIR OPDs, and further introduce their applications in all-organic optical upconversion devices and photoplethysmography sensors. In particular, the relationship between the chemical structure and the aggregation behaviors of polymethine dyes and the device performance is carefully discussed, providing some important molecular insights for developing high performance NIR OPDs.展开更多
Comprehensive Summary 2D materials have attracted intensive attention due to their unique electrical and optical properties associated with their strictly defined low dimensionalities.They provide a wide range of basi...Comprehensive Summary 2D materials have attracted intensive attention due to their unique electrical and optical properties associated with their strictly defined low dimensionalities.They provide a wide range of basic building blocks for future electronics and optoelectronics.The chemical vapor deposition(CVD)has been proposed to be efficient to realize the controllable thickness,scalable size,which are necessary for both industrial applications and fundamental researches.Herein,we share our research works to realize the controllable growth of 2D materials.We found that stable growth microenvironment can regulate the growth of 2D materials.Thus,we developed near-steady source supply,space-confined,and additive-assisted passivated growth methods to solve the problem of unstable growth environment caused by uneven source and mass transfer.Then,we developed several strategies to precisely control the parity,separation,and transport of the carriers in 2D materials including fabricating defect-free interface via van der Waals dielectrics,modulating the parity of carriers via ferroelectric-field,and the separation of carriers via band engineering.Toward future development,we highlight the opportunities and challenges inthis field.展开更多
In this work, a three-layer TiO2 composite film consisting of flower-like TiO2 (Flo-TiO2) as overlayer, TiOa nanotube arrays as interlayer and TiO2 nanoparticle (P25) as underlayer was fabricated as the photoelect...In this work, a three-layer TiO2 composite film consisting of flower-like TiO2 (Flo-TiO2) as overlayer, TiOa nanotube arrays as interlayer and TiO2 nanoparticle (P25) as underlayer was fabricated as the photoelectrode of dyesensitized solar cells (DSSCs). Due to the introduction of Flo-TiO2, the three-layer composite film has strong lightscattering ability. Then, we have investigated and compared the photoelectric conversion properties of DSSCs based on three-layer structure (P25/TNT arrays/Flo-TiO2) photoelectrode and double-layer film (P25/TNT arrays) photoelectrode. It is found that DSSCs based on three-layer structure exhibit a high power conversion efficiency of 6.48% compared with the DSSCs composed of double-layer film (5.11%).展开更多
基金funded by National Natural Science Foundation of China(No.52073045)the Key Scientific and Technological Project of Jilin Province(No.20190701010GH)+2 种基金the Development and Reform Commission of Jilin Province(No.2020C0355)the support from the Key Laboratory of Nanobiosensing and Nanobioanalysis at the Universities of Jilin Provincethe support from the Jilin Provincial Department of Education。
文摘We develop the effective modification strategy based on molecular engineering of s-triazine and its derivatives to improve the photoelectric performance of all-inorganic perovskites(AIP)for the first time.The surface modification strategy with cyanuric acid successfully increases the PLQY of AIP from 40.55%to 88.15%,and significantly enhances the current of the AIP film under 3 V by almost 20-fold(from4.44 m A to 81.20 m A).This work has proven the effectiveness of improving the photoelectric performances of AIP via s-triazine and its derivatives and also suggested the potential risks of reducing the photoelectric performance of AIP due to inappropriate substituents in conjugated organic ligands.
基金supported by the National Defense Pre-Research Foundation of China(No.51311050301095)
文摘A design of an inverse U-shape buried doping in a pinned photodiode (PPD) of CMOS image sensors is proposed for electrical crosstalk suppression between adjacent pixels. The architecture achieves no extra fill factor consumption, and proper built-in electric fields can be established according to the doping gradient created by the injections of the extremely low P-type doping buried regions in the epitaxial layer, causing the excess electrons to easily drift back to the photosensitive area rarely with a diffusion probability; the overall junction capacitance and photosensitive area extensions for a full well capacity (FWC) and internal quantum efficiency (IQE) improving are achieved by the injection of a buried N-type doping. By considering the image lag issue, the process parameters of all the injections have been precisely optimized. Optical simulation results based on the finite difference time domain method show that compared to the conventional PPD, the electrical crosstalk rate of the proposed architecture can be decreased by 60%-80% at an incident wavelength beyond 450 nm, IQE can be clearly improved at an incident wavelength between 400 and 600 nm, and the FWC can be enhanced by 107.5%. Furthermore, the image lag performance is sustained to a perfect low level. The present study provides important guidance on the design of ultra high resolution image sensors.
基金financially supported by the National Natural Science Foundation of China(Nos.21975085 and 22175067)the excellent Youth Foundation of Hubei Scientific Committee(No.2021CFA065)+1 种基金the Innovation and Talent Recruitment Base of New Energy Chemistry and Device(No.B21003)the Fundamental Research Funds for the Central Universities(No.2021yjsCXCY060).
文摘Near-infrared organic photodiodes (NIR OPDs) have tremendous potential in industrial, military, and scientific applications, due to their unique features of lightweight, low toxicity, high structural flexibility, cooling-system-free, etc. However, the overall performance of currently available NIR OPDs still lags behind the commercial inorganic photodetectors, ascribed to the critical challenge of realizing organic semiconductors with sufficiently low optical bandgap and excellent optoelectronic properties simultaneously. Among various types of NIR-absorbing organic semiconductors, polymethine dyes not only possess advantages of simple synthesis and structural diversity, but also show fascinating optical and aggregation features in the solid state, making them attractive material candidates for NIR OPDs. In this review, after a brief introduction of NIR OPDs and polymethine dyes, we comprehensively summarize the advances of polymethine dyes for broadband and narrowband NIR OPDs, and further introduce their applications in all-organic optical upconversion devices and photoplethysmography sensors. In particular, the relationship between the chemical structure and the aggregation behaviors of polymethine dyes and the device performance is carefully discussed, providing some important molecular insights for developing high performance NIR OPDs.
基金supported by the National Natural Science Foundation of China(Grant Nos.21825103,52172144,and U21A2069)the Ministry of Science and Technology of China(2021YFA1200500).
文摘Comprehensive Summary 2D materials have attracted intensive attention due to their unique electrical and optical properties associated with their strictly defined low dimensionalities.They provide a wide range of basic building blocks for future electronics and optoelectronics.The chemical vapor deposition(CVD)has been proposed to be efficient to realize the controllable thickness,scalable size,which are necessary for both industrial applications and fundamental researches.Herein,we share our research works to realize the controllable growth of 2D materials.We found that stable growth microenvironment can regulate the growth of 2D materials.Thus,we developed near-steady source supply,space-confined,and additive-assisted passivated growth methods to solve the problem of unstable growth environment caused by uneven source and mass transfer.Then,we developed several strategies to precisely control the parity,separation,and transport of the carriers in 2D materials including fabricating defect-free interface via van der Waals dielectrics,modulating the parity of carriers via ferroelectric-field,and the separation of carriers via band engineering.Toward future development,we highlight the opportunities and challenges inthis field.
基金supported by the National Natural Science Foundation of China (Nos. 51572072 and 11204070)the Fundamental Research Funds for the Central Universities (No. 2014-Ia-028)financially supported by State Key Laboratory of Advanced Technology for Materials Synthesis and Processing (No. 2016-KF-13)
文摘In this work, a three-layer TiO2 composite film consisting of flower-like TiO2 (Flo-TiO2) as overlayer, TiOa nanotube arrays as interlayer and TiO2 nanoparticle (P25) as underlayer was fabricated as the photoelectrode of dyesensitized solar cells (DSSCs). Due to the introduction of Flo-TiO2, the three-layer composite film has strong lightscattering ability. Then, we have investigated and compared the photoelectric conversion properties of DSSCs based on three-layer structure (P25/TNT arrays/Flo-TiO2) photoelectrode and double-layer film (P25/TNT arrays) photoelectrode. It is found that DSSCs based on three-layer structure exhibit a high power conversion efficiency of 6.48% compared with the DSSCs composed of double-layer film (5.11%).