Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP),of much interest owing to its high ionic conductivity,superior air stability,and low cost,has been regarded as one of the most promising solid-state electrolytes for next-gen...Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP),of much interest owing to its high ionic conductivity,superior air stability,and low cost,has been regarded as one of the most promising solid-state electrolytes for next-generation solid-state lithium batteries(SSLBs).Unfortunately,the commercialization of SSLBs is still impeded by severe interfacial issues,such as high interfacial impedance and poor chemical stability.Herein,we proposed a simple and convenient in-situ approach to constructing a tight and robust interface between the Li anode and LATP electrolyte via a SnO_(2)gradient buffer layer.It is firmly attached to the surface of LATP pellets due to the volume expansion of SnO_(2)when in-situ reacting with Li metal,and thus effectively alleviates the physical contact loosening during cycling,as confirmed by the mitigated impedance rising.Meanwhile,the as-formed SnO_(2)/Sn/LixSn gradient buffer layer with low electronic conductivity successfully protects the LATP electrolyte surface from erosion by the Li metal anode.Additionally,the LixSn alloy formed at the Li surface can effectively regulate uniform lithium deposition and suppress Li dendrite growth.Therefore,this work paves a new way to simultaneously address the chemical instability and poor physical contact of LATP with Li metal in developing low-cost and highly stable SSLBs.展开更多
In the past few years,the all-solid lithium battery has attracted worldwide attentions,the ionic conductivity of some all-solid lithium-ion batteries has reached 10^(-3)-10^(-2) S/cm,indicating that the transport of l...In the past few years,the all-solid lithium battery has attracted worldwide attentions,the ionic conductivity of some all-solid lithium-ion batteries has reached 10^(-3)-10^(-2) S/cm,indicating that the transport of lithium ions in solid electrolytes is no longer a major problem.However,some interface issues become research hotspots.Examples of these interfacial issues include the electrochemical decomposition reaction at the electrode-electrolyte interface;the low effective contact area between the solid electrolyte and the electrode etc.In order to solve the issues,researchers have pursued many different approaches.The addition of a buffer layer between the electrode and the solid electrolyte has been at the center of this endeavor.In this review paper,we provide a systematic summarization of the problems on the electrode-solid electrolyte interface and detailed reflection on the latest works of buffer-based therapies,and the review will end with a personal perspective on the improvement of buffer-based therapies.展开更多
The interface between the active layer and the electrode is one of the most critical factors that could affect the device performance of polymer solar cells. In this work, based on the typical poly(3-hexylthiophene)...The interface between the active layer and the electrode is one of the most critical factors that could affect the device performance of polymer solar cells. In this work, based on the typical poly(3-hexylthiophene):[6,6]-phenyl C61-butyric acid methyl ester (P3HT:PCBM) polymer solar cell, we studied the effect of the cathode buffer layer (CBL) between the top metal electrode and the active layer on the device performance. Several inorganic and organic materials commonly used as the electron injection layer in an organic light-emitting diode (OLED) were employed as the CBL in the P3HT:PCBM polymer solar cells. Our results demonstrate that the inorganic and organic materials like Cs2CO3, bathophenanthroline (Bphen), and 8-hydroxyquinolatolithium (Liq) can be used as CBL to efficiently improve the device performance of the P3HT:PCBM polymer solar cells. The P3HT:PCBM devices employed various CBLs possess power conversion efficiencies (PCEs) of 3.0%-3.3%, which are ca. 50% improved compared to that of the device without CBL. Furthermore, by using the doped organic materials Bphen:Cs2CO3 and Bphen:Liq as the CBL, the PCE of the P3HT:PCBM device will be further improved to 3.5%, which is ca. 70% higher than that of the device without a CBL and ca. 10% increased compared with that of the devices with a neat inorganic or organic CBL.展开更多
A silicon carbide (SIC) based metal semiconductor field effect transistor (MESFET) is fabricated by using a standard SiC MESFET structure with the application of a dual p-buffer layer and a multi-recessed gate to ...A silicon carbide (SIC) based metal semiconductor field effect transistor (MESFET) is fabricated by using a standard SiC MESFET structure with the application of a dual p-buffer layer and a multi-recessed gate to the process for an S-band power amplifier. The lower doped upper-buffer layer serves to maintain the channel current, while the higher doped lowerbuffer layer is used to provide excellent electron confinement in the channel layer. A 20-mm gate periphery SiC MESFET biased at a drain voltage of 85 V demonstrates a pulsed wave saturated output power of 94 W, a linear gain of 11.7 dB, and a maximum power added efficiency of 24.3% at 3.4 GHz. These results are improved compared with those of the conventional single p-buffer MESFET fabricated in this work using the same process. A radio-frequency power output greater than 4.7 W/mm is achieved, showing the potential as a high-voltage operation device for high-power solid-state amplifier applications.展开更多
When we use MOCVD technique,an excellent CdTe epi-layer was grown on GaAs substrates and the CdTe/GaAs hybrid substrates suitable for growing Hg_(1-x)Cd_xTe(CMT)were obtained.The x value in CMT is between 0.2 and 0.8....When we use MOCVD technique,an excellent CdTe epi-layer was grown on GaAs substrates and the CdTe/GaAs hybrid substrates suitable for growing Hg_(1-x)Cd_xTe(CMT)were obtained.The x value in CMT is between 0.2 and 0.8.The electrical properties of CMT depend upon the thickness of CdTe epi-layers.The CdTe/GaAs interface was examined by both scanning electron microscope(SEM)and electron auger spectra (EAS).The influence of defects observed at interface on electrical and optical properties of CMT fihns was dis- cussed.展开更多
Microcrystalline silicon(μc-Si:H) solar cell with graded band gap microcrystalline silicon oxide(μc-SiOx:H) buffer layer is prepared by plasma enhanced chemical vapor deposition and exhibits improved performan...Microcrystalline silicon(μc-Si:H) solar cell with graded band gap microcrystalline silicon oxide(μc-SiOx:H) buffer layer is prepared by plasma enhanced chemical vapor deposition and exhibits improved performance compared with the cell without it. The buffer layer moderates the band gap mismatch by reducing the barrier of the p/i interface, which promotes the nucleation of the i-layer and effectively eliminates the incubation layer, and then enhances the collection efficiency of the cell in the short wavelength region of the spectrum. The p/i interface defect density also decreases from 2.2 × 10^12cm^-2to 5.0 × 10^11cm^-2. This graded buffer layer allows to simplify the deposition process for the μc-Si:H solar cell application.展开更多
通过利用 TEM研究 Si Cp/ Al- Si复合材料发现 :Si C/ Al界面结合紧密 ,在靠近 Si C界面的 Al基体中 ,有一层厚度小于 1μm的“亚晶铝带”,它紧靠 Si C表面形成 ,与远离 Si C的 Al基体有几度的位向差 ;这种“亚晶铝带”在 Si C/ Al界面...通过利用 TEM研究 Si Cp/ Al- Si复合材料发现 :Si C/ Al界面结合紧密 ,在靠近 Si C界面的 Al基体中 ,有一层厚度小于 1μm的“亚晶铝带”,它紧靠 Si C表面形成 ,与远离 Si C的 Al基体有几度的位向差 ;这种“亚晶铝带”在 Si C/ Al界面上普遍存在 ,其内有大量位错。展开更多
Hydrogenated microcrystalline silicon (μc-Si:H) intrinsic films and solar cells with n-i-p configuration were prepared by plasma enhanced chemical vapor deposition (PECVD). The influence of n/i and i/p buffer la...Hydrogenated microcrystalline silicon (μc-Si:H) intrinsic films and solar cells with n-i-p configuration were prepared by plasma enhanced chemical vapor deposition (PECVD). The influence of n/i and i/p buffer layers on the μc-Si:H cell performance was studied in detail. The experimental results demonstrated that the efficiency is much improved when there is a higher crystallinity at n/i interface and an optimized a-Si:H buffer layer at i/p interface. By combining the above methods, the performance of μc-Si:H single-junction and a-Si:H/μc-Si:H tandem solar cells has been significantly improved.展开更多
A methanol-soluble diamine-modified fullerene derivative(denoted as PCBDANI)was applied as an efficient cathode buffer layer(CBL)in planar p-i-n perovskite solar cells(pero-SCs)based on the CH_3NH_3PbI_(3-x)Cl_x absor...A methanol-soluble diamine-modified fullerene derivative(denoted as PCBDANI)was applied as an efficient cathode buffer layer(CBL)in planar p-i-n perovskite solar cells(pero-SCs)based on the CH_3NH_3PbI_(3-x)Cl_x absorber.The device with PCBDANI single CBL exhibited significantly improved performance with a power conversion efficiency(PCE)of 15.45%,which is approximately17%higher than that of the control device without the CBL.The dramatic improvement in PCE can be attributed to the formation of an interfacial dipole at the PCBM/Al interface originating from the amine functional group and the suppression of interfacial recombinationby the PCBDANI interlayer.To further improve the PCE of pero-SCs,PCBDANI/LiF double CBLs were introduced between PCBM and the top Al electrode.An impressive PCE of 15.71%was achieved,which is somewhat higher than that of the devices with LiF or PCBDANI single CBL.Besides the PCE,the long-term stability of the device with PCBDANI/LiF double CBLs is also superior to that of the device with LiF single CBL.展开更多
基金financially supported by the China Postdoctoral Science Foundation(2021M700396)the National Natural Science Foundation of China(52102206)the research grants from the National Research Foundation(2022K1A3A1A20014496 and 2022R1F1A1074707)funded by the government of the Republic of Korea。
文摘Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP),of much interest owing to its high ionic conductivity,superior air stability,and low cost,has been regarded as one of the most promising solid-state electrolytes for next-generation solid-state lithium batteries(SSLBs).Unfortunately,the commercialization of SSLBs is still impeded by severe interfacial issues,such as high interfacial impedance and poor chemical stability.Herein,we proposed a simple and convenient in-situ approach to constructing a tight and robust interface between the Li anode and LATP electrolyte via a SnO_(2)gradient buffer layer.It is firmly attached to the surface of LATP pellets due to the volume expansion of SnO_(2)when in-situ reacting with Li metal,and thus effectively alleviates the physical contact loosening during cycling,as confirmed by the mitigated impedance rising.Meanwhile,the as-formed SnO_(2)/Sn/LixSn gradient buffer layer with low electronic conductivity successfully protects the LATP electrolyte surface from erosion by the Li metal anode.Additionally,the LixSn alloy formed at the Li surface can effectively regulate uniform lithium deposition and suppress Li dendrite growth.Therefore,this work paves a new way to simultaneously address the chemical instability and poor physical contact of LATP with Li metal in developing low-cost and highly stable SSLBs.
基金financially supported by the Fundamental Research Funds for the Central Universities of China(No.FRF-BD-19-008A)the Brain Pool program funded by the Ministry of Science and ICT through the National Research Foundation of Korea(No.2019H1D3A2A02100593)the National Research Foundation of Korea(NRF)grant funded by the Korean government(Nos.2019R1C1C 1006310,2020R1I1A1A01072996,2021K2A9A2A06044652,and 2019R1A2C1002844).
文摘In the past few years,the all-solid lithium battery has attracted worldwide attentions,the ionic conductivity of some all-solid lithium-ion batteries has reached 10^(-3)-10^(-2) S/cm,indicating that the transport of lithium ions in solid electrolytes is no longer a major problem.However,some interface issues become research hotspots.Examples of these interfacial issues include the electrochemical decomposition reaction at the electrode-electrolyte interface;the low effective contact area between the solid electrolyte and the electrode etc.In order to solve the issues,researchers have pursued many different approaches.The addition of a buffer layer between the electrode and the solid electrolyte has been at the center of this endeavor.In this review paper,we provide a systematic summarization of the problems on the electrode-solid electrolyte interface and detailed reflection on the latest works of buffer-based therapies,and the review will end with a personal perspective on the improvement of buffer-based therapies.
基金Project supported by the National Natural Science Foundation of China(Grant No.61204014)the“Chenguang”Project(13CG42)+1 种基金supported by Shanghai Municipal Education Commission and Shanghai Education Development Foundation,Chinathe Shanghai University Young Teacher Training Program of Shanghai Municipality,China
文摘The interface between the active layer and the electrode is one of the most critical factors that could affect the device performance of polymer solar cells. In this work, based on the typical poly(3-hexylthiophene):[6,6]-phenyl C61-butyric acid methyl ester (P3HT:PCBM) polymer solar cell, we studied the effect of the cathode buffer layer (CBL) between the top metal electrode and the active layer on the device performance. Several inorganic and organic materials commonly used as the electron injection layer in an organic light-emitting diode (OLED) were employed as the CBL in the P3HT:PCBM polymer solar cells. Our results demonstrate that the inorganic and organic materials like Cs2CO3, bathophenanthroline (Bphen), and 8-hydroxyquinolatolithium (Liq) can be used as CBL to efficiently improve the device performance of the P3HT:PCBM polymer solar cells. The P3HT:PCBM devices employed various CBLs possess power conversion efficiencies (PCEs) of 3.0%-3.3%, which are ca. 50% improved compared to that of the device without CBL. Furthermore, by using the doped organic materials Bphen:Cs2CO3 and Bphen:Liq as the CBL, the PCE of the P3HT:PCBM device will be further improved to 3.5%, which is ca. 70% higher than that of the device without a CBL and ca. 10% increased compared with that of the devices with a neat inorganic or organic CBL.
基金Project supported by the National Natural Science Foundation of China (Grant No. 61076072)
文摘A silicon carbide (SIC) based metal semiconductor field effect transistor (MESFET) is fabricated by using a standard SiC MESFET structure with the application of a dual p-buffer layer and a multi-recessed gate to the process for an S-band power amplifier. The lower doped upper-buffer layer serves to maintain the channel current, while the higher doped lowerbuffer layer is used to provide excellent electron confinement in the channel layer. A 20-mm gate periphery SiC MESFET biased at a drain voltage of 85 V demonstrates a pulsed wave saturated output power of 94 W, a linear gain of 11.7 dB, and a maximum power added efficiency of 24.3% at 3.4 GHz. These results are improved compared with those of the conventional single p-buffer MESFET fabricated in this work using the same process. A radio-frequency power output greater than 4.7 W/mm is achieved, showing the potential as a high-voltage operation device for high-power solid-state amplifier applications.
文摘When we use MOCVD technique,an excellent CdTe epi-layer was grown on GaAs substrates and the CdTe/GaAs hybrid substrates suitable for growing Hg_(1-x)Cd_xTe(CMT)were obtained.The x value in CMT is between 0.2 and 0.8.The electrical properties of CMT depend upon the thickness of CdTe epi-layers.The CdTe/GaAs interface was examined by both scanning electron microscope(SEM)and electron auger spectra (EAS).The influence of defects observed at interface on electrical and optical properties of CMT fihns was dis- cussed.
基金supported by the Key Basic Research Project of Hebei Province,China(Grant Nos.12963930D and 12963929D)the Natural Science Foundation of Hebei Province,China(Grant Nos.F2013201250 and E2012201059)the Science and Technology Research Projects of the Education Department of Hebei Province,China(Grant No.ZH2012030)
文摘Microcrystalline silicon(μc-Si:H) solar cell with graded band gap microcrystalline silicon oxide(μc-SiOx:H) buffer layer is prepared by plasma enhanced chemical vapor deposition and exhibits improved performance compared with the cell without it. The buffer layer moderates the band gap mismatch by reducing the barrier of the p/i interface, which promotes the nucleation of the i-layer and effectively eliminates the incubation layer, and then enhances the collection efficiency of the cell in the short wavelength region of the spectrum. The p/i interface defect density also decreases from 2.2 × 10^12cm^-2to 5.0 × 10^11cm^-2. This graded buffer layer allows to simplify the deposition process for the μc-Si:H solar cell application.
基金supported by the State Key Development Program for Basic Research of China (Nos. 2006CB202602, 2006CB202603)the Tianjin Assistant Foundation for the National Basic Research Program of China (No. 07QTPTJC29500).
文摘Hydrogenated microcrystalline silicon (μc-Si:H) intrinsic films and solar cells with n-i-p configuration were prepared by plasma enhanced chemical vapor deposition (PECVD). The influence of n/i and i/p buffer layers on the μc-Si:H cell performance was studied in detail. The experimental results demonstrated that the efficiency is much improved when there is a higher crystallinity at n/i interface and an optimized a-Si:H buffer layer at i/p interface. By combining the above methods, the performance of μc-Si:H single-junction and a-Si:H/μc-Si:H tandem solar cells has been significantly improved.
基金the National Natural Science Foundation of China(21204054,51303118,91333204)the Natural Science Foundation of Jiangsu Province(BK20130289)+3 种基金the Ph.D.Programs Foundation of Ministry of Education of China(20133201120008)the Priority Academic Program Development of Jiangsu Higher Education Institutionsthe Scientific Research Foundation for Returned Scholars,Ministry of Education of ChinaBeijing National Laboratory for Molecular Sciences,State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials
文摘A methanol-soluble diamine-modified fullerene derivative(denoted as PCBDANI)was applied as an efficient cathode buffer layer(CBL)in planar p-i-n perovskite solar cells(pero-SCs)based on the CH_3NH_3PbI_(3-x)Cl_x absorber.The device with PCBDANI single CBL exhibited significantly improved performance with a power conversion efficiency(PCE)of 15.45%,which is approximately17%higher than that of the control device without the CBL.The dramatic improvement in PCE can be attributed to the formation of an interfacial dipole at the PCBM/Al interface originating from the amine functional group and the suppression of interfacial recombinationby the PCBDANI interlayer.To further improve the PCE of pero-SCs,PCBDANI/LiF double CBLs were introduced between PCBM and the top Al electrode.An impressive PCE of 15.71%was achieved,which is somewhat higher than that of the devices with LiF or PCBDANI single CBL.Besides the PCE,the long-term stability of the device with PCBDANI/LiF double CBLs is also superior to that of the device with LiF single CBL.