We report a transition metal such as manganese doped methylammonium lead halide perovskite(MA(Pb:Mn)I_(3)) solar cell with an power conversion efficiency(PCE) over 20%. The rational design and fabrication of MA(Pb:Mn)...We report a transition metal such as manganese doped methylammonium lead halide perovskite(MA(Pb:Mn)I_(3)) solar cell with an power conversion efficiency(PCE) over 20%. The rational design and fabrication of MA(Pb:Mn)I3 lead to the enhancements of all the photovoltaic parameters. To incorporate Mn can effectively eliminate the trap-assist and bi-molecular recombination. The photo-absorption ability at shorter wavelengths(i.e., less than 500 nm) and charge carrier lifetime can be elaborated. More importantly, the existence of the Mn^(2+)-I~--Mn^(3+)motif contributes for the double exchange effect, giving rise to the charge/spin transport. By a combination of linearly and circularly polarized photo-excitations, we have explicitly determined the role of intrinsic spin–orbit coupling(SOC) in MA(Pb:Mn)I_(3). More dark states are expected to be available for the photocurrent generation. This study may pave the way for deep understandings of transition metals doped hybrid perovskites for highly efficient solar cell applications.展开更多
Piezoelectric ceramics based on Pb(Zr_xTi_(1-x))O_3(PZT)are widely used in electronic and microelectronic devices.Most commercially available PZT formulations have Curie temperature T_C～300℃which limits the operatin...Piezoelectric ceramics based on Pb(Zr_xTi_(1-x))O_3(PZT)are widely used in electronic and microelectronic devices.Most commercially available PZT formulations have Curie temperature T_C～300℃which limits the operating temperatures to～150℃.However,a number of piezoelectric applications require operating at higher temperatures than are currently available with conventional PZT ceramics.Eitel et al.used a perovskite tolerance factor relationship with T_C to predict that Bi(Me)O_3-PbTiO_3 systems(Me:Sc,In,Y,Y...展开更多
The redox property and oxygen species play an important role in the catalytic oxidation of volatile organic compounds(VOCs).In this paper,a series of Mn_(x)Co_(3-x)O_(4)catalysts with tubular structure were synthesize...The redox property and oxygen species play an important role in the catalytic oxidation of volatile organic compounds(VOCs).In this paper,a series of Mn_(x)Co_(3-x)O_(4)catalysts with tubular structure were synthesized and applied for the catalytic combustion of toluene.Various characterization technologies were employed to reveal the relationship between the catalytic performance of the Mn_(x)Co_(3-x)O_(4)catalysts and Mn doping.The results of XRD,SEM and N2 adsorption-desorption analyses showed that the Mn doping had significant effects on the structure and morphology of the Mn_(x)Co_(3-x)O_(4)catalysts.The H2-TPR,O2-TPD,and XPS results proved that the strong interaction between Co and Mn resulted in the enhanced Olatt mobility,the richer active oxygen species,and the enhanced redox property in comparison with the pure Co_(3)O_(4)sample,which were crucial to the improvement of the catalytic activity of Co-Mn catalysts.The best catalyst,Co5-Mn5 sample,exhibited a good and stable activity to catalytically oxidize toluene at low temperatures even in the presence of water vapor,indicating that it is a potential material to be used in the commercialization of catalytic abatement of toluene.展开更多
Pure and Mn-doped NaTaO3 nanoparticles were synthesized by a simple hydro- thermal method. XRD and XPS results suggested that manganese ions were successfully doped into the NaTaO3 crystalline in Mn2＋ state. UV-vis d...Pure and Mn-doped NaTaO3 nanoparticles were synthesized by a simple hydro- thermal method. XRD and XPS results suggested that manganese ions were successfully doped into the NaTaO3 crystalline in Mn2＋ state. UV-vis diffuse reflectance spectra revealed the obvious red-shift in the series of manganese doped NaTaO3 nanoparticles, resulting in a decrease in the band gap of NaTaO3 with the increase of Mn2＋ doping concentration. The photo-degradation experiment indicated that manganese doped NaTaO3 showed good photocatalytic performance and methylene blue（MB） degradation is improved with lower doping concentration of manganese ions under visible light. The simulation of energy band structure by density functional theory unfolded that the substitution of Ta5＋ ions by Mn2＋ ions resulted in an intermediate band（IB） below the bottom of the conduction band（CB）, which was mainly attributed to the state of Mn 3d.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 61634001, 11942413, 61974010, and 61904011)the Intergovernmental Cooperation Project, National Key Research and Development Program, Ministry of Science and Technology, China (Grant No. 2019YFE0108400)。
文摘We report a transition metal such as manganese doped methylammonium lead halide perovskite(MA(Pb:Mn)I_(3)) solar cell with an power conversion efficiency(PCE) over 20%. The rational design and fabrication of MA(Pb:Mn)I3 lead to the enhancements of all the photovoltaic parameters. To incorporate Mn can effectively eliminate the trap-assist and bi-molecular recombination. The photo-absorption ability at shorter wavelengths(i.e., less than 500 nm) and charge carrier lifetime can be elaborated. More importantly, the existence of the Mn^(2+)-I~--Mn^(3+)motif contributes for the double exchange effect, giving rise to the charge/spin transport. By a combination of linearly and circularly polarized photo-excitations, we have explicitly determined the role of intrinsic spin–orbit coupling(SOC) in MA(Pb:Mn)I_(3). More dark states are expected to be available for the photocurrent generation. This study may pave the way for deep understandings of transition metals doped hybrid perovskites for highly efficient solar cell applications.
文摘Piezoelectric ceramics based on Pb(Zr_xTi_(1-x))O_3(PZT)are widely used in electronic and microelectronic devices.Most commercially available PZT formulations have Curie temperature T_C～300℃which limits the operating temperatures to～150℃.However,a number of piezoelectric applications require operating at higher temperatures than are currently available with conventional PZT ceramics.Eitel et al.used a perovskite tolerance factor relationship with T_C to predict that Bi(Me)O_3-PbTiO_3 systems(Me:Sc,In,Y,Y...
基金This work is supported by the Interdisciplinary Integration and Innovation Project of JLU(JLUXKJC 2020204)the National Natural Science Foundation of China(No.51672276,51772294,51972306)the Fundamental Research Funds for the Central Universities,JLU.
文摘The redox property and oxygen species play an important role in the catalytic oxidation of volatile organic compounds(VOCs).In this paper,a series of Mn_(x)Co_(3-x)O_(4)catalysts with tubular structure were synthesized and applied for the catalytic combustion of toluene.Various characterization technologies were employed to reveal the relationship between the catalytic performance of the Mn_(x)Co_(3-x)O_(4)catalysts and Mn doping.The results of XRD,SEM and N2 adsorption-desorption analyses showed that the Mn doping had significant effects on the structure and morphology of the Mn_(x)Co_(3-x)O_(4)catalysts.The H2-TPR,O2-TPD,and XPS results proved that the strong interaction between Co and Mn resulted in the enhanced Olatt mobility,the richer active oxygen species,and the enhanced redox property in comparison with the pure Co_(3)O_(4)sample,which were crucial to the improvement of the catalytic activity of Co-Mn catalysts.The best catalyst,Co5-Mn5 sample,exhibited a good and stable activity to catalytically oxidize toluene at low temperatures even in the presence of water vapor,indicating that it is a potential material to be used in the commercialization of catalytic abatement of toluene.
基金Supported by the National Natural Science Foundation of China(Nos.21103081 and 21267014)the Project of Scientific and Technological Innovation Team of Inner Mongolia University(12110614)
文摘Pure and Mn-doped NaTaO3 nanoparticles were synthesized by a simple hydro- thermal method. XRD and XPS results suggested that manganese ions were successfully doped into the NaTaO3 crystalline in Mn2＋ state. UV-vis diffuse reflectance spectra revealed the obvious red-shift in the series of manganese doped NaTaO3 nanoparticles, resulting in a decrease in the band gap of NaTaO3 with the increase of Mn2＋ doping concentration. The photo-degradation experiment indicated that manganese doped NaTaO3 showed good photocatalytic performance and methylene blue（MB） degradation is improved with lower doping concentration of manganese ions under visible light. The simulation of energy band structure by density functional theory unfolded that the substitution of Ta5＋ ions by Mn2＋ ions resulted in an intermediate band（IB） below the bottom of the conduction band（CB）, which was mainly attributed to the state of Mn 3d.
