The numerical simulations were performed using the AMPS-1D simulator to study the effects of the CZTS as an absorber layer and the contacts’barrier height on the performance of four ZnO/CdS/CZTS solar cells.To obtain...The numerical simulations were performed using the AMPS-1D simulator to study the effects of the CZTS as an absorber layer and the contacts’barrier height on the performance of four ZnO/CdS/CZTS solar cells.To obtain the best cell performances,the barrier heights of the back and front contacts were adjusted between 0.01,0.77,0.5,and 1.55 eV,respectively.For simulations,we used the lifetime mode,and the device performances were evaluated under AM1.5 illumination spectra.We found that the efficiency,fill factor,and open-circuit voltage were almost constant at a front contact barrier height of less than 0.31 eV.The short-current density was not affected by the front contact barrier height.The back contact material had a significant impact on the CZTS cells parameters.The best performance was obtained for the CZTS550 cell with JSC=29.53 mA/cm2,VOC=1.07 V,FF=0.88,andη=28.08%at barrier heights of 0.31 and 1.55 eV for front and back contacts,respectively.The conduction band offset at the CZTS550/CdS hetero-junction was found to be spike-like with 0.21 eV.The obtained conversion efficiency is comparable to those previously reported in the literature.展开更多
Cu(In, Al)Se2 thin films were prepared by electrodeposition from the aqueous solution consisting of CuCl2, InCl3, AlCl3 and SeO2 onto ITO coated glass substrates. The as-deposited films were annealed under vacuum for ...Cu(In, Al)Se2 thin films were prepared by electrodeposition from the aqueous solution consisting of CuCl2, InCl3, AlCl3 and SeO2 onto ITO coated glass substrates. The as-deposited films were annealed under vacuum for 30 min at temperature ranging between 200°C and 400°C. The structural, composition, morphology, optical band gap and electrical resistivity of elaborated thin films were studied, respectively using x-ray diffraction, energy dispersive analysis of x-ray, scanning electron microscopy, UV spectrophotometer and four-point probe method. The lattice constant and structural parameters viz. crystallite size, dislocation density and strain of the films were also calculated. After vacuum annealing, x-ray diffraction results revealed that all films were polycrystalline in nature and exhibit chalcopyrite structure with (112) as preferred orientation. The film annealed at 350°C showed the coexistence of CIASe and InSe phases. The average crystallite size increases linearly with annealing temperature, reaching a maximum value for 350°C. The films show a direct allowed band gap which increases from 1.59 to 1.78 eV with annealing temperature. We have also found that the electrical resistivity of films is controlled by the carrier concentration rather than by their mobility.展开更多
文摘The numerical simulations were performed using the AMPS-1D simulator to study the effects of the CZTS as an absorber layer and the contacts’barrier height on the performance of four ZnO/CdS/CZTS solar cells.To obtain the best cell performances,the barrier heights of the back and front contacts were adjusted between 0.01,0.77,0.5,and 1.55 eV,respectively.For simulations,we used the lifetime mode,and the device performances were evaluated under AM1.5 illumination spectra.We found that the efficiency,fill factor,and open-circuit voltage were almost constant at a front contact barrier height of less than 0.31 eV.The short-current density was not affected by the front contact barrier height.The back contact material had a significant impact on the CZTS cells parameters.The best performance was obtained for the CZTS550 cell with JSC=29.53 mA/cm2,VOC=1.07 V,FF=0.88,andη=28.08%at barrier heights of 0.31 and 1.55 eV for front and back contacts,respectively.The conduction band offset at the CZTS550/CdS hetero-junction was found to be spike-like with 0.21 eV.The obtained conversion efficiency is comparable to those previously reported in the literature.
文摘Cu(In, Al)Se2 thin films were prepared by electrodeposition from the aqueous solution consisting of CuCl2, InCl3, AlCl3 and SeO2 onto ITO coated glass substrates. The as-deposited films were annealed under vacuum for 30 min at temperature ranging between 200°C and 400°C. The structural, composition, morphology, optical band gap and electrical resistivity of elaborated thin films were studied, respectively using x-ray diffraction, energy dispersive analysis of x-ray, scanning electron microscopy, UV spectrophotometer and four-point probe method. The lattice constant and structural parameters viz. crystallite size, dislocation density and strain of the films were also calculated. After vacuum annealing, x-ray diffraction results revealed that all films were polycrystalline in nature and exhibit chalcopyrite structure with (112) as preferred orientation. The film annealed at 350°C showed the coexistence of CIASe and InSe phases. The average crystallite size increases linearly with annealing temperature, reaching a maximum value for 350°C. The films show a direct allowed band gap which increases from 1.59 to 1.78 eV with annealing temperature. We have also found that the electrical resistivity of films is controlled by the carrier concentration rather than by their mobility.