Through theoretical analyses of the Shockley equation and the difference between a practical P-N junction and its ideal model, the mathematical models of P-N junction and solar cells had been obtained. With Matlab sof...Through theoretical analyses of the Shockley equation and the difference between a practical P-N junction and its ideal model, the mathematical models of P-N junction and solar cells had been obtained. With Matlab software, the V-I characteristics of diodes and solar cells were simulated, and a computer simulation model of the solar cells based on P-N junction was also established. Based on the simulation model, the influences of solar cell’s internal resistances on open-circuit voltage and short-circuit current under certain illumination were numerically analyzed and solved. The simulation results showed that the equivalent series resistance and shunt resistance could strongly affect the V-I characteristics of solar cell, but their influence styles were different.展开更多
In the present paper, some novel opportunities for the development of high-efficient Si and III-V-based solar cells are considered: energy-saving environment friendly low-temperature technology of forming p-n junction...In the present paper, some novel opportunities for the development of high-efficient Si and III-V-based solar cells are considered: energy-saving environment friendly low-temperature technology of forming p-n junctions in Si (1), elaboration of structurally perfect GaAs/Ge/Si epitaxial substrates (2) and application of protective antireflecting coatings based on cubic zirconia (3). As a result: 1) New technique of forming p-n junctions in silicon has been elaborated. The technique provided easy and comparatively cheap process of production of semiconductor devices such as solar cells. The essence of the technique under the study is comprised in formation p-n junctions in silicon by a change of conductivity in the bulk of the sample occurring as a result of redistribution of the impurities, which already exists in the sample before its processing by ions. It differs from the techniques of diffusion and ion doping where change of conductivity and formation of p-n junction in the sample occur as a result of introduction of atoms of the other dopants from the outside;2) The conditions for synthesis of GaAs/Ge/Si epitaxial substrates with a thin (200 nm) Ge buffer layer featured with (1 - 2) × 105 cm-2 density of the threading dislocation in the GaAs layer. Ge buffer was obtained by chemical vapor deposition with a hot wire and GaAs layer of 1 μm thick was grown by the metal organic chemical vapor deposition. Root mean square surface roughness of GaAs layers of the less than 1 nm and good photoluminescence properties along with their high uniformity were obtained;3) The conditions ensuring the synthesis of uniform functional (buffer, insulating and protective) fianite layers on Si and GaAs substrates by means of magnetron and electron-beam sputtering have been determined. Fianite films have been shown to be suitable for the use as an ideal anti-reflecting material with high protective and anticorrosive properties.展开更多
Polymer light-emitting electrochemical cells (PLECs) employ a thin layer of a luminescent conjugated polymer admixed with an ionic source and an ionic conductor for the in-situ formation of p-i-n junction and subseque...Polymer light-emitting electrochemical cells (PLECs) employ a thin layer of a luminescent conjugated polymer admixed with an ionic source and an ionic conductor for the in-situ formation of p-i-n junction and subsequent efficient injections of both electrons and holes.The junction formation enables the use of air-stable conductors as the cathode and a relatively thick emissive polymer layer that is more compatible with low-cost solution-based processes.This paper overviews the operation mechanism of the PLECs,the properties and drawbacks of the devices.The employment of crosslinkable ionic conductors to stabilize the p-i-n junction is reviewed.The resulting static junction electroluminesces light at high brightness,high efficiency,and prolonged lifetime.Silver paste and carbon nanotubes can be used as the cathode,thus,PLECs were fabricated by lamination.Using single wall carbon nanotubes coated elastic substrate as both anode and cathode,the PLECs can be made highly stretchable.展开更多
基于胶质量子点(CQD)半导体材料的第三代薄膜太阳能电池,因为材料的量子尺寸调谐特性,在宽光谱太阳能发电领域有其独特的优势。该文将CQD薄膜近似为传统半导体材料,介绍了CQD太阳能电池的工作原理及表征电池性能的主要参数,指明了CQD材...基于胶质量子点(CQD)半导体材料的第三代薄膜太阳能电池,因为材料的量子尺寸调谐特性,在宽光谱太阳能发电领域有其独特的优势。该文将CQD薄膜近似为传统半导体材料,介绍了CQD太阳能电池的工作原理及表征电池性能的主要参数,指明了CQD材料与块半导体材料的差异,分析了影响CQD电池性能的材料方面的几个因素。按照研究的时间顺序,回顾了6种结构的Pb S CQD电池发展情况及最新现状,指出提升材料性能,改进材料中光电转换过程的物理模型,及优化器件结构都能够帮助提高CQD电池的效率。展开更多
The P+ α-Si /N+ polycrystalline solar cell is molded using the AMPS-1D device simulator to explore the new high efficiency thin film poly-silicon solar cell. In order to analyze the characteristics of this device and...The P+ α-Si /N+ polycrystalline solar cell is molded using the AMPS-1D device simulator to explore the new high efficiency thin film poly-silicon solar cell. In order to analyze the characteristics of this device and the thickness of N+ poly-silicon, we consider the impurity concentration in the N+ poly-silicon layer and the work function of transparent conductive oxide (TCO) in front contact in the calculation. The thickness of N+ poly-silicon has little impact on the device when the thickness varies from 20 μm to 300 μm. The effects of impurity concentration in polycrystalline are analyzed. The conclusion is drawn that the open-circuit voltage (Voc) of P+ α-Si /N+ polycrystalline solar cell is very high, reaching 752 mV, and the conversion efficiency reaches 9.44%. Therefore, based on the above optimum parameters the study on the device formed by P+ α-Si/N+ poly-silicon is significant in exploring the high efficiency poly-silicon solar cell.展开更多
Light-emitting electrochemical cells(LECs) are organic photonic devices based on a mixed electronic and ionic conductor.The active layer of a polymer-based LEC consists of a luminescent polymer,an ion-solvating/transp...Light-emitting electrochemical cells(LECs) are organic photonic devices based on a mixed electronic and ionic conductor.The active layer of a polymer-based LEC consists of a luminescent polymer,an ion-solvating/transport polymer,and a compatible salt.The LEC p-n or p-i-n junction is ultimately responsible for the LEC performance.The LEC junction,however,is still poorly understood due to the difficulties of characterizing a dynamic-junction LEC.In this paper,we present an experimental and modeling study of the LEC junction using scanning optical imaging techniques.Planar LECs with an interelectrode spacing of 560μm have been fabricated,activated,frozen and scanned using a focused laser beam.The optical-beam-induced-current(OBIC)and photoluminescence(PL) data have been recorded as a function of beam location.The OBIC profile has been simulated in COMSOL that allowed for the determination of the doping concentration and the depletion width of the LEC junction.展开更多
文摘Through theoretical analyses of the Shockley equation and the difference between a practical P-N junction and its ideal model, the mathematical models of P-N junction and solar cells had been obtained. With Matlab software, the V-I characteristics of diodes and solar cells were simulated, and a computer simulation model of the solar cells based on P-N junction was also established. Based on the simulation model, the influences of solar cell’s internal resistances on open-circuit voltage and short-circuit current under certain illumination were numerically analyzed and solved. The simulation results showed that the equivalent series resistance and shunt resistance could strongly affect the V-I characteristics of solar cell, but their influence styles were different.
文摘In the present paper, some novel opportunities for the development of high-efficient Si and III-V-based solar cells are considered: energy-saving environment friendly low-temperature technology of forming p-n junctions in Si (1), elaboration of structurally perfect GaAs/Ge/Si epitaxial substrates (2) and application of protective antireflecting coatings based on cubic zirconia (3). As a result: 1) New technique of forming p-n junctions in silicon has been elaborated. The technique provided easy and comparatively cheap process of production of semiconductor devices such as solar cells. The essence of the technique under the study is comprised in formation p-n junctions in silicon by a change of conductivity in the bulk of the sample occurring as a result of redistribution of the impurities, which already exists in the sample before its processing by ions. It differs from the techniques of diffusion and ion doping where change of conductivity and formation of p-n junction in the sample occur as a result of introduction of atoms of the other dopants from the outside;2) The conditions for synthesis of GaAs/Ge/Si epitaxial substrates with a thin (200 nm) Ge buffer layer featured with (1 - 2) × 105 cm-2 density of the threading dislocation in the GaAs layer. Ge buffer was obtained by chemical vapor deposition with a hot wire and GaAs layer of 1 μm thick was grown by the metal organic chemical vapor deposition. Root mean square surface roughness of GaAs layers of the less than 1 nm and good photoluminescence properties along with their high uniformity were obtained;3) The conditions ensuring the synthesis of uniform functional (buffer, insulating and protective) fianite layers on Si and GaAs substrates by means of magnetron and electron-beam sputtering have been determined. Fianite films have been shown to be suitable for the use as an ideal anti-reflecting material with high protective and anticorrosive properties.
基金supported by the National Science Foundation (ECCS1028412)
文摘Polymer light-emitting electrochemical cells (PLECs) employ a thin layer of a luminescent conjugated polymer admixed with an ionic source and an ionic conductor for the in-situ formation of p-i-n junction and subsequent efficient injections of both electrons and holes.The junction formation enables the use of air-stable conductors as the cathode and a relatively thick emissive polymer layer that is more compatible with low-cost solution-based processes.This paper overviews the operation mechanism of the PLECs,the properties and drawbacks of the devices.The employment of crosslinkable ionic conductors to stabilize the p-i-n junction is reviewed.The resulting static junction electroluminesces light at high brightness,high efficiency,and prolonged lifetime.Silver paste and carbon nanotubes can be used as the cathode,thus,PLECs were fabricated by lamination.Using single wall carbon nanotubes coated elastic substrate as both anode and cathode,the PLECs can be made highly stretchable.
文摘基于胶质量子点(CQD)半导体材料的第三代薄膜太阳能电池,因为材料的量子尺寸调谐特性,在宽光谱太阳能发电领域有其独特的优势。该文将CQD薄膜近似为传统半导体材料,介绍了CQD太阳能电池的工作原理及表征电池性能的主要参数,指明了CQD材料与块半导体材料的差异,分析了影响CQD电池性能的材料方面的几个因素。按照研究的时间顺序,回顾了6种结构的Pb S CQD电池发展情况及最新现状,指出提升材料性能,改进材料中光电转换过程的物理模型,及优化器件结构都能够帮助提高CQD电池的效率。
基金supported by the Natural Science Foundation of Fujian Province of China (Grant No. A0220001)Science Research Project of Leshan Vocational & Technical College (Grant No. KY2011001)the Key Research Project in Science and Technology of Leshan (Grant No. 2011GZD050)
文摘The P+ α-Si /N+ polycrystalline solar cell is molded using the AMPS-1D device simulator to explore the new high efficiency thin film poly-silicon solar cell. In order to analyze the characteristics of this device and the thickness of N+ poly-silicon, we consider the impurity concentration in the N+ poly-silicon layer and the work function of transparent conductive oxide (TCO) in front contact in the calculation. The thickness of N+ poly-silicon has little impact on the device when the thickness varies from 20 μm to 300 μm. The effects of impurity concentration in polycrystalline are analyzed. The conclusion is drawn that the open-circuit voltage (Voc) of P+ α-Si /N+ polycrystalline solar cell is very high, reaching 752 mV, and the conversion efficiency reaches 9.44%. Therefore, based on the above optimum parameters the study on the device formed by P+ α-Si/N+ poly-silicon is significant in exploring the high efficiency poly-silicon solar cell.
基金supported by the Natural Sciences and Engineering Research Council of Canada.Faleh AlTal is supported by an Ontario Trillium Fellowship
文摘Light-emitting electrochemical cells(LECs) are organic photonic devices based on a mixed electronic and ionic conductor.The active layer of a polymer-based LEC consists of a luminescent polymer,an ion-solvating/transport polymer,and a compatible salt.The LEC p-n or p-i-n junction is ultimately responsible for the LEC performance.The LEC junction,however,is still poorly understood due to the difficulties of characterizing a dynamic-junction LEC.In this paper,we present an experimental and modeling study of the LEC junction using scanning optical imaging techniques.Planar LECs with an interelectrode spacing of 560μm have been fabricated,activated,frozen and scanned using a focused laser beam.The optical-beam-induced-current(OBIC)and photoluminescence(PL) data have been recorded as a function of beam location.The OBIC profile has been simulated in COMSOL that allowed for the determination of the doping concentration and the depletion width of the LEC junction.