Abstract: Transient photocurrents induced by shoft light pulses at lanice-mathed GaAs/Alx.Ga1-x multiple quantum well (MQW) electrodes were studied as a function of electrode potential. Dual exponential photocurrent d...Abstract: Transient photocurrents induced by shoft light pulses at lanice-mathed GaAs/Alx.Ga1-x multiple quantum well (MQW) electrodes were studied as a function of electrode potential. Dual exponential photocurrent decay indents were observed at various potentials. By analysis of the dual exponented decay transients, information on steady state photocurrents (Is). surface collection of photoexcoted mmority cCarriers(GO) and lifetimes of surfaCe states (Ts) was obtained. The kinetic behaviors of photoprocesses at illuminated MQW/electrolyte interface were discussed.展开更多
Single quantum wells(SQWs)of GaAs/Al_xGa_(1-x)As have been investigated as photoelectrodes in photoelectrochemical cells.Structured photocurrent spectra for well widths of 50 and 100 SQWs were obtained in nonaqueous s...Single quantum wells(SQWs)of GaAs/Al_xGa_(1-x)As have been investigated as photoelectrodes in photoelectrochemical cells.Structured photocurrent spectra for well widths of 50 and 100 SQWs were obtained in nonaqueous solution.The dependence of structured photocurrent spectra on electrode potential were exhibited.The quantum yield was higher in SQW with 100 well compared to 50 well.展开更多
It is well known that conventional CalnP/GMnAs/Ce three-junction (3J) solar cells are difficult to continue to ascend when the effieiencies reach 32% and 42% under AMO and AM1.5D concentrated, respectively. In AlCaI...It is well known that conventional CalnP/GMnAs/Ce three-junction (3J) solar cells are difficult to continue to ascend when the effieiencies reach 32% and 42% under AMO and AM1.5D concentrated, respectively. In AlCaInP/AiGMnAs/CalnAs/CalnNAs/Ce five-junction (5,/) solar cells, the performance of the AlGaInP, Al- CalnAs and CalnNAs sub cell is the key factor for conversion efficiency of the 5J solar cell. We investigate the AlCaInP/AlCaInAs/Ge 3J solar cell. By incorporating surfactant trimthylantimony into the AlGaInP material, the crystal quality of AICalnP is improved and the spectrum absorption range of AICalnAs is extended. The current density of each sub cell exceeds ll.3mA/cm2 as is desired. Then we apply this 3J structure to grow the lattice-matched 5J solar ceil and obtain the short circuit current of 134.96 mA, open circuit voltage of 4399.6 m V, fill factor of 81.7% and conversion efficiency of 29.87%.展开更多
The notorious dendrite and infinite volume change seriously restrict the advancement of lithium metal anodes(LMAs),during the long-term process of stripping/plating.Herein,the nanosheets of metal fluoride(CoF_(2))and ...The notorious dendrite and infinite volume change seriously restrict the advancement of lithium metal anodes(LMAs),during the long-term process of stripping/plating.Herein,the nanosheets of metal fluoride(CoF_(2))and metal nitride(CoN)with magnificent lithiophilicity on the nickel(Ni)foam are designed as the“regulator”to uniform the Li plating and build stronger solid electrolyte interface(SEI)layer for dendrite free LMAs.The Ni foam offers abundant space to receive deposited Li metal.The CoN nanosheets can guarantee the fast transfer of electrons,which provides a stable interface of Li^(+)reduction.Moreover,the nanosheet structure with lithiophilicity would accelerate the move of Li+and decrease the nucleation barrier,due to the high lattice-matching of Li and CoN.Meanwhile,the CoF_(2) could increase the content of F(LiF)in the SEI layer,which enhances the strength and avoids the destruction of SEI layer.With the cooperation of CoN and CoF_(2),the composited anode(Li/NF@CNCF)exhibits ultra-long cycle performance(more than 1200 h)and fantastic structure stability at 1 mA·cm^(-2) with 1 mAh·cm^(-2).Based on the LiFePO_(4) and Li/NF@CNCF,the full cells deliver excellent specifical capacity and steady coulombic efficiency.The strategy contributes an effective approach to alleviate the issues of lithium metal anodes in the field of LMAs.展开更多
Within density functional theory based on the full potentiM-linearized augmented plane wave method, we carry out the first-principles calculation of the structural, electronic, and optical properties of the zinc blend...Within density functional theory based on the full potentiM-linearized augmented plane wave method, we carry out the first-principles calculation of the structural, electronic, and optical properties of the zinc blende quaternary alloy Zn1-xBexSySe1-y. The Perdew-Burke-Ernzerhof generaized gradient approximation based on the optimization of total energy and the Engel-Vosko generalized gradient approximation based on the optimization of the corresponding potential are used. Our investigation on the effect of the composition on lattice constants, bulk modulus, band gap, optical dielectric constant, and refractive index shows a non-linear dependence. The energy gap Eg(x, y) has been determined over the entire compositions x and y. In addition, the energy band gap of the technologically important quaternary alloy Znl-xBexSySe1-y in conditions of being lattice matched to ZnS substrate has been investigated. It is noteworthy that the present work is the first theoretical study of the quaternary alloy of interest.展开更多
The controlled self-assembly of organic heterostructures(OHSs)with precisely defined compositions,architectures,and interfaces,have largely remained a challenge.Herein,we introduce an effective approach to accurately ...The controlled self-assembly of organic heterostructures(OHSs)with precisely defined compositions,architectures,and interfaces,have largely remained a challenge.Herein,we introduce an effective approach to accurately construct three types of axial branching OHSs including unilateral axial OHSs,bilateral single-branching axial OHSs and bilateral multi-branching axial OHSs through modulating hierarchical charge-transfer intermolecular interactions and sequential crystal nucleation rate on account of the two different cocrystals with the low lattice mismatching rate of~2.2%.The present work opens an avenue for rationally designing and finely synthesizing more kinds of OHSs.展开更多
文摘Abstract: Transient photocurrents induced by shoft light pulses at lanice-mathed GaAs/Alx.Ga1-x multiple quantum well (MQW) electrodes were studied as a function of electrode potential. Dual exponential photocurrent decay indents were observed at various potentials. By analysis of the dual exponented decay transients, information on steady state photocurrents (Is). surface collection of photoexcoted mmority cCarriers(GO) and lifetimes of surfaCe states (Ts) was obtained. The kinetic behaviors of photoprocesses at illuminated MQW/electrolyte interface were discussed.
基金This work was supported by the National Natural Science Foundation of China.
文摘Single quantum wells(SQWs)of GaAs/Al_xGa_(1-x)As have been investigated as photoelectrodes in photoelectrochemical cells.Structured photocurrent spectra for well widths of 50 and 100 SQWs were obtained in nonaqueous solution.The dependence of structured photocurrent spectra on electrode potential were exhibited.The quantum yield was higher in SQW with 100 well compared to 50 well.
文摘It is well known that conventional CalnP/GMnAs/Ce three-junction (3J) solar cells are difficult to continue to ascend when the effieiencies reach 32% and 42% under AMO and AM1.5D concentrated, respectively. In AlCaInP/AiGMnAs/CalnAs/CalnNAs/Ce five-junction (5,/) solar cells, the performance of the AlGaInP, Al- CalnAs and CalnNAs sub cell is the key factor for conversion efficiency of the 5J solar cell. We investigate the AlCaInP/AlCaInAs/Ge 3J solar cell. By incorporating surfactant trimthylantimony into the AlGaInP material, the crystal quality of AICalnP is improved and the spectrum absorption range of AICalnAs is extended. The current density of each sub cell exceeds ll.3mA/cm2 as is desired. Then we apply this 3J structure to grow the lattice-matched 5J solar ceil and obtain the short circuit current of 134.96 mA, open circuit voltage of 4399.6 m V, fill factor of 81.7% and conversion efficiency of 29.87%.
基金supported by the Fundamental Research Funds for the Central Universities(No.3132023503).
文摘The notorious dendrite and infinite volume change seriously restrict the advancement of lithium metal anodes(LMAs),during the long-term process of stripping/plating.Herein,the nanosheets of metal fluoride(CoF_(2))and metal nitride(CoN)with magnificent lithiophilicity on the nickel(Ni)foam are designed as the“regulator”to uniform the Li plating and build stronger solid electrolyte interface(SEI)layer for dendrite free LMAs.The Ni foam offers abundant space to receive deposited Li metal.The CoN nanosheets can guarantee the fast transfer of electrons,which provides a stable interface of Li^(+)reduction.Moreover,the nanosheet structure with lithiophilicity would accelerate the move of Li+and decrease the nucleation barrier,due to the high lattice-matching of Li and CoN.Meanwhile,the CoF_(2) could increase the content of F(LiF)in the SEI layer,which enhances the strength and avoids the destruction of SEI layer.With the cooperation of CoN and CoF_(2),the composited anode(Li/NF@CNCF)exhibits ultra-long cycle performance(more than 1200 h)and fantastic structure stability at 1 mA·cm^(-2) with 1 mAh·cm^(-2).Based on the LiFePO_(4) and Li/NF@CNCF,the full cells deliver excellent specifical capacity and steady coulombic efficiency.The strategy contributes an effective approach to alleviate the issues of lithium metal anodes in the field of LMAs.
文摘Within density functional theory based on the full potentiM-linearized augmented plane wave method, we carry out the first-principles calculation of the structural, electronic, and optical properties of the zinc blende quaternary alloy Zn1-xBexSySe1-y. The Perdew-Burke-Ernzerhof generaized gradient approximation based on the optimization of total energy and the Engel-Vosko generalized gradient approximation based on the optimization of the corresponding potential are used. Our investigation on the effect of the composition on lattice constants, bulk modulus, band gap, optical dielectric constant, and refractive index shows a non-linear dependence. The energy gap Eg(x, y) has been determined over the entire compositions x and y. In addition, the energy band gap of the technologically important quaternary alloy Znl-xBexSySe1-y in conditions of being lattice matched to ZnS substrate has been investigated. It is noteworthy that the present work is the first theoretical study of the quaternary alloy of interest.
基金The authors acknowledge financial support from the National Natural Science Foundation of China(Nos.21971185,51821002)this project is also funded by the Collaborative Innovation Center of Suzhou Nano Science and Technology(CIC-Nano)+1 种基金by the“111”Project of the State Administration of Foreign Experts Affairs of Chinaby the National Natural Science Foundation of China(Nos.52173177,21971185).
文摘The controlled self-assembly of organic heterostructures(OHSs)with precisely defined compositions,architectures,and interfaces,have largely remained a challenge.Herein,we introduce an effective approach to accurately construct three types of axial branching OHSs including unilateral axial OHSs,bilateral single-branching axial OHSs and bilateral multi-branching axial OHSs through modulating hierarchical charge-transfer intermolecular interactions and sequential crystal nucleation rate on account of the two different cocrystals with the low lattice mismatching rate of~2.2%.The present work opens an avenue for rationally designing and finely synthesizing more kinds of OHSs.