ZnSe as a surface passivation layer in quantum dot-sensitized solar cells plays an important role in preventing charge recombination and thus improves the power conversion efficiency(PCE).However, as a wide bandgap se...ZnSe as a surface passivation layer in quantum dot-sensitized solar cells plays an important role in preventing charge recombination and thus improves the power conversion efficiency(PCE).However, as a wide bandgap semiconductor, ZnSe cannot efficiently absorb and convert long-wavelength light.Doping transition metal ions into ZnSe semiconductors is an effective way to adjust the band gap, such as manganese ions.In this paper, it is found by the method of density functional theory calculation that the valence band of ZnSe moves upward with manganese ions doping, which leads to acceleration of charge separation, wider light absorption range, and enhancing light harvesting.Finally, by using ZnSe doped with manganese ions as the passivation layer, the TiO2/CdS/CdSe co-sensitized solar cell has a PCE of 6.12%, and the PCE of the solar cell increases by 9% compared with the undoped one(5.62%).展开更多
For zinc air batteries,a non-noble metal-based electrocatalyst with a high performance and stability in oxygen evolution reaction(OER)and oxygen reduction reaction(ORR)is imperative in application.Herein,a catalyst ba...For zinc air batteries,a non-noble metal-based electrocatalyst with a high performance and stability in oxygen evolution reaction(OER)and oxygen reduction reaction(ORR)is imperative in application.Herein,a catalyst based on FeCo-N encapsuled in nitrogen-doped carbon nanotubes has been prepared,which provides an implementable method to design controlled structures with excellent bifunction al electrocatalytic activities.By adjusting the molar ratio of two metals,the synthesized FeCo-N-C catalyst delivers a competitive ORR and OER performance compared with commercial Pt/C and IrO_(2),performing a low overvoltage gap between ORR(E_(1/2))and OER(E_(j=10))of 0.8 V.Moreover,as a promising cathode in zinc air battery,the FeCo-N-C catalyst possesses an affirmative stability of over 100 h and large power density(129 mW·cm^(-2)).This work demonstrates that FeCo-N-C is one of the most promising catalysts for zinc air batteries and provides a possibility for exploration of batteries with high stability by adjusting the molar ratio of metals in the catalysts.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61376011,61704114,51402141,and 61604086)the Gansu Provincial Natural Science Foundation,China(Grant No.17JR5RA198)+2 种基金the Fundamental Research Funds for the Central Universities,China(Grant Nos.lzujbky-2018-119 and lzujbky-2018-ct08)the Fund from Shenzhen Science and Technology Innovation Committee,China(Grant No.JCYJ20170818155813437)the Key Areas Scientific and Technological Research Projects in Xinjiang Production and Construction Corps(Grant No.2018AB004)
文摘ZnSe as a surface passivation layer in quantum dot-sensitized solar cells plays an important role in preventing charge recombination and thus improves the power conversion efficiency(PCE).However, as a wide bandgap semiconductor, ZnSe cannot efficiently absorb and convert long-wavelength light.Doping transition metal ions into ZnSe semiconductors is an effective way to adjust the band gap, such as manganese ions.In this paper, it is found by the method of density functional theory calculation that the valence band of ZnSe moves upward with manganese ions doping, which leads to acceleration of charge separation, wider light absorption range, and enhancing light harvesting.Finally, by using ZnSe doped with manganese ions as the passivation layer, the TiO2/CdS/CdSe co-sensitized solar cell has a PCE of 6.12%, and the PCE of the solar cell increases by 9% compared with the undoped one(5.62%).
基金financially supported by Gansu Provincial Natural Science Foundation of China(Nos.17JR5RA198,2020HZ-2)the Cooperation project of Gansu Academy of Sciences(No.2020HZ-2)+1 种基金the Fundamental Research Funds for the Central Universities(Nos.lzujbky-2018-119,lzujbky-2018-ct08,lzujbky-2019-it23)the Key Areas Scientific and Technological Research Projects in Xinjiang Production and Construction Corps(No.2018AB004)。
文摘For zinc air batteries,a non-noble metal-based electrocatalyst with a high performance and stability in oxygen evolution reaction(OER)and oxygen reduction reaction(ORR)is imperative in application.Herein,a catalyst based on FeCo-N encapsuled in nitrogen-doped carbon nanotubes has been prepared,which provides an implementable method to design controlled structures with excellent bifunction al electrocatalytic activities.By adjusting the molar ratio of two metals,the synthesized FeCo-N-C catalyst delivers a competitive ORR and OER performance compared with commercial Pt/C and IrO_(2),performing a low overvoltage gap between ORR(E_(1/2))and OER(E_(j=10))of 0.8 V.Moreover,as a promising cathode in zinc air battery,the FeCo-N-C catalyst possesses an affirmative stability of over 100 h and large power density(129 mW·cm^(-2)).This work demonstrates that FeCo-N-C is one of the most promising catalysts for zinc air batteries and provides a possibility for exploration of batteries with high stability by adjusting the molar ratio of metals in the catalysts.