The Experts below are selected from a list of 23577 Experts worldwide ranked by ideXlab platform
Fei Huang - One of the best experts on this subject based on the ideXlab platform.
-
impacts of surface or interface chemistry of znse Passivation Layer on the performance of cds cdse quantum dot sensitized solar cells
Nano Energy, 2017Co-Authors: Fei Huang, Qifeng Zhang, Hongen Wang, Hao Tang, Lisha Zhang, Shanglong PengAbstract:Abstract ZnSe deposited via successive ionic Layer adsorption and reaction (SILAR) method onto TiO 2 /CdS/CdSe photoanode has been proven as an effective Passivation Layer to suppressing charge recombination and enhancing power conversion efficiency in quantum dot-sensitized solar cells (QDSCs). However, the device performance varies appreciably with the deposition process as the chemical identity and the interfacial structure between the Passivation Layer and the quantum dots and electrolytes have retained quite some unanswered questions. The present paper reports the significant impacts of ZnSe Passivation Layer with different surface or interface chemistry on the performance of CdS/CdSe QDSCs. The photovoltaic properties show that the performance of assembled cells has a strong dependence on the SILAR immersion sequences started with Zn 2+ or Se 2- . When Zn 2+ was initially deposited, the unintentionally formed QDs/ZnSe/Se/SeO 2 structure with a large amount of ZnSe leads to a significant increase in the photovoltaic properties. When Se 2- was first deposited, most of the Se 2- absorbed on the surface of the photoanode would be oxidized to form Se° and SeO 2 , with a small fraction of ZnSe formed. The resulted QDs/Se/SeO 2 /ZnSe structure leads to a drastic decrease of the solar cell performance.
-
doubling the power conversion efficiency in cds cdse quantum dot sensitized solar cells with a znse Passivation Layer
Nano Energy, 2016Co-Authors: Fei Huang, Qifeng Zhang, Yuan Wang, Robert C Masse, Shanglong Peng, Huanli WangAbstract:Abstract The surface Passivation Layer in quantum dot sensitized solar cells (QDSSCs) plays a very important role in preventing surface charge recombination and, thus, improving the power conversion efficiency. The present study demonstrated the introduction of a ZnSe Passivation Layer prepared with a successive ionic Layer absorption and reaction (SILAR) method in CdS/CdSe co-sensitized solar cells, though not likely in the ideal form of a conformal overLayer, have significantly enhanced the power conversion efficiency, which was found to be far more efficient than the most widely used ZnS Passivation Layer. Not only can the ZnSe Passivation Layer reduce surface charge recombination, but can also enhance the light harvesting. The short-circuit current density, open-circuit voltage, fill factor, and the corresponding photovoltaic conversion efficiency were all significantly improved with the introduction of a ZnSe Passivation Layer but varied appreciably with the Layer thickness. When three SILAR cycle Layer was applied, the power conversion efficiency is as high as 6.4%, which is almost doubled the efficiency of 3.4% for the solar cell without ZnSe Passivation Layer. For the comparison, the CdS/CdSe co-sensitized solar cells with optimum ZnS Passivation Layer was also fabricated, which generated a power conversion efficiency of 4.9%, much lower than 6.4% of ZnSe passivated QDSSCs. This work demonstrated that ZnSe would be a good alternative to ZnS as a Passivation material.
J R Morante - One of the best experts on this subject based on the ideXlab platform.
-
insight on the su 8 resist as Passivation Layer for transparent ga2o3 in2o3 zno thin film transistors
Journal of Applied Physics, 2010Co-Authors: Antonis Olziersky, Pedro Barquinha, A Vila, Luis Pereira, Goncalo Goncalves, Elvira Fortunato, Rodrigo Martins, J R MoranteAbstract:A nonvacuum and low temperature process for passivating transparent metal oxides based thin-film transistors is presented. This process uses the epoxy-based SU-8 resist which prevents device degradation against environmental conditions, vacuum or sputtering surface damage. The incorporation of SU-8 as a Passivation Layer is based on the ability of this polymer to provide features with high mechanical and chemical stability. With this approach, lithography is performed to pattern the resist over the active area of the device in order to form the Passivation Layer. The resulting transistors demonstrate very good electrical characteristics, such as μFE=61 cm2/V s, VON=−3 V, ON/OFF=4.4×109, and S=0.28 V/dec. Electrical behavior due to the SU-8/metal oxide interface characteristics is also reported on the basis of Fourier transform infrared analysis. In contrast, we demonstrate how sputtering of SiO2 as a Passivation Layer results in severely degraded devices that cannot be switched-off. In order to obtain pro...
Shanglong Peng - One of the best experts on this subject based on the ideXlab platform.
-
impacts of surface or interface chemistry of znse Passivation Layer on the performance of cds cdse quantum dot sensitized solar cells
Nano Energy, 2017Co-Authors: Fei Huang, Qifeng Zhang, Hongen Wang, Hao Tang, Lisha Zhang, Shanglong PengAbstract:Abstract ZnSe deposited via successive ionic Layer adsorption and reaction (SILAR) method onto TiO 2 /CdS/CdSe photoanode has been proven as an effective Passivation Layer to suppressing charge recombination and enhancing power conversion efficiency in quantum dot-sensitized solar cells (QDSCs). However, the device performance varies appreciably with the deposition process as the chemical identity and the interfacial structure between the Passivation Layer and the quantum dots and electrolytes have retained quite some unanswered questions. The present paper reports the significant impacts of ZnSe Passivation Layer with different surface or interface chemistry on the performance of CdS/CdSe QDSCs. The photovoltaic properties show that the performance of assembled cells has a strong dependence on the SILAR immersion sequences started with Zn 2+ or Se 2- . When Zn 2+ was initially deposited, the unintentionally formed QDs/ZnSe/Se/SeO 2 structure with a large amount of ZnSe leads to a significant increase in the photovoltaic properties. When Se 2- was first deposited, most of the Se 2- absorbed on the surface of the photoanode would be oxidized to form Se° and SeO 2 , with a small fraction of ZnSe formed. The resulted QDs/Se/SeO 2 /ZnSe structure leads to a drastic decrease of the solar cell performance.
-
doubling the power conversion efficiency in cds cdse quantum dot sensitized solar cells with a znse Passivation Layer
Nano Energy, 2016Co-Authors: Fei Huang, Qifeng Zhang, Yuan Wang, Robert C Masse, Shanglong Peng, Huanli WangAbstract:Abstract The surface Passivation Layer in quantum dot sensitized solar cells (QDSSCs) plays a very important role in preventing surface charge recombination and, thus, improving the power conversion efficiency. The present study demonstrated the introduction of a ZnSe Passivation Layer prepared with a successive ionic Layer absorption and reaction (SILAR) method in CdS/CdSe co-sensitized solar cells, though not likely in the ideal form of a conformal overLayer, have significantly enhanced the power conversion efficiency, which was found to be far more efficient than the most widely used ZnS Passivation Layer. Not only can the ZnSe Passivation Layer reduce surface charge recombination, but can also enhance the light harvesting. The short-circuit current density, open-circuit voltage, fill factor, and the corresponding photovoltaic conversion efficiency were all significantly improved with the introduction of a ZnSe Passivation Layer but varied appreciably with the Layer thickness. When three SILAR cycle Layer was applied, the power conversion efficiency is as high as 6.4%, which is almost doubled the efficiency of 3.4% for the solar cell without ZnSe Passivation Layer. For the comparison, the CdS/CdSe co-sensitized solar cells with optimum ZnS Passivation Layer was also fabricated, which generated a power conversion efficiency of 4.9%, much lower than 6.4% of ZnSe passivated QDSSCs. This work demonstrated that ZnSe would be a good alternative to ZnS as a Passivation material.
Sung-hwan Choi - One of the best experts on this subject based on the ideXlab platform.
-
Effect of Deposition Temperature of SiOx Passivation Layer on the Electrical Performance of a-IGZO TFTs
IEEE Electron Device Letters, 2012Co-Authors: Sung-hwan ChoiAbstract:We investigated the effect of the deposition temperature on the electrical performance of SiOx Passivation Layers for amorphous indium-gallium-zinc-oxide thin-film transistors (a-IGZO TFTs). Compared to the time-of-flight secondary ion mass spectroscopy depth profile of the IGZO film with a SiOx Passivation Layer deposited at low temperature (150oC ), that with the SiOx film formed at 300oC exhibited the significant migration of metal ions from the IGZO film into the SiOx Passivation Layer. These results were attributed to the high-energy ion bombardment on the IGZO channel Layer. In order to suppress the interdiffusion of In, Ga, and Zn atoms between the IGZO and Passivation Layers, we proposed double SiOx Passivation using different substrate temperatures. It combines the merits of low-temperature (150oC) and high-temperature (300oC) Passivations and compensates for their individual weaknesses. We confirmed the enhanced electrical characteristics and improved reliability of the IGZO TFTs compared to those of the conventional device.
Fanying Meng - One of the best experts on this subject based on the ideXlab platform.
-
underdense a si h film capped by a dense film as the Passivation Layer of a silicon heterojunction solar cell
Journal of Applied Physics, 2016Co-Authors: Liping Zhang, Renfang Chen, Fanying MengAbstract:Underdense hydrogenated amorphous silicon (a-Si:H) prepared by plasma-enhanced chemical vapor deposition was used as a Passivation Layer in silicon heterojunction (SHJ) solar cells. By reducing the thickness of the underdense a-Si:H Passivation Layer from 15 nm to 5 nm, the open circuit voltage (Voc) of the corresponding SHJ solar cell increased significantly from 724.3 mV to 738.6 mV. For comparison, a widely used transition-zone a-Si:H Passivation Layer was also examined, but reducing its thickness from 15 nm to 5 nm resulted in a continuous Voc reduction, from 724.1 mV to 704.3 mV. The highest efficiency was achieved using a 5-nm-thick underdense a-Si:H Passivation Layer. We propose that this advantageous property of underdense a-Si:H reflects its microstructural characteristics. While the porosity of a-Si:H Layer enables H penetration into the amorphous network and the a-Si:H/c-Si interface, a high degree of disorder inhibits the formation of the epitaxial Layer at the a-Si:H/c-Si interface during pos...