The preparation of bifunctional catalysts for oxygen reduction(ORR)and oxygen evolution(OER)is crucial for Zn-air batteries.Here,we report a La doped CoFe_(2)O_(4) spinel catalyst supported on threedimensional graphen...The preparation of bifunctional catalysts for oxygen reduction(ORR)and oxygen evolution(OER)is crucial for Zn-air batteries.Here,we report a La doped CoFe_(2)O_(4) spinel catalyst supported on threedimensional graphene(3D-G),where La can facilitate electron transfer from Co to Fe,leading to increased electron cloud density in Fe and improved catalytic performance.The redshift of the G peak in the Raman spectra indicates the interaction between theπbond of 3D-G and d orbitals in La_(0.2)CoFe_(1.8)O_(4).La_(0.2)CoFe_(1.8)/3D-G exhibits superior ORR performance(E_(1/2)=0.86 V vs.RHE)and OER performance(E_(j=10)=1.55 V vs.RHE)to CoFe_(2)O_(4)/3D-G(E_(1/2)=0.831 V vs.RHE,E_(j=10)=1.603 V vs.RHE).Furthermore,it demonstrates excellent bifunctional oxygen catalytic performance while maintaining high power density and stability in liquid zinc-air batteries(ZABs)and flexible ZABs(F-ZABs).This work presents a viable strategy for utilizing rare earth element doped spinels to enhance oxygen catalyst and ZABs performance.展开更多
Three methods,isotopic tracing,fluorescence quenching and electrophysiological technique, are normally used to study transmernbrane transport. Planar lipid bilayer system is an electrophysiological method,in which art...Three methods,isotopic tracing,fluorescence quenching and electrophysiological technique, are normally used to study transmernbrane transport. Planar lipid bilayer system is an electrophysiological method,in which artificial lipid and electrical measurement are used to simulate the ion-permeability of bio-membrane.It can展开更多
Recent progress in ultrafast lasers,ultrafast X-rays and ultrafast electron beams has made it possible to watch the motion of atoms in real time through pumpprobe technique.In this review,we focus on how the molecular...Recent progress in ultrafast lasers,ultrafast X-rays and ultrafast electron beams has made it possible to watch the motion of atoms in real time through pumpprobe technique.In this review,we focus on how the molecular dynamics can be studied with ultrafast electron diffraction where the dynamics is initiated by a pumping laser and then probed by pulsed electron beams.This technique allows one to track the molecular dynamics with femtosecond time resolution and Angstr6m spatial resolution.We present the basic physics and latest development of this technique.Representative applications of ultrafast electron diffraction in studies of laser-induced molecular dynamics are also discussed.This table-top technique is complementary to X-ray free-electron laser and we expect it to have a strong impact in studies of chemical dynamics.展开更多
基金financially supported by the National Natural Science Foundation of China(22172093 and 21776167)the Natural Science Foundation of Shandong Province,China(ZR2023MB061).
文摘The preparation of bifunctional catalysts for oxygen reduction(ORR)and oxygen evolution(OER)is crucial for Zn-air batteries.Here,we report a La doped CoFe_(2)O_(4) spinel catalyst supported on threedimensional graphene(3D-G),where La can facilitate electron transfer from Co to Fe,leading to increased electron cloud density in Fe and improved catalytic performance.The redshift of the G peak in the Raman spectra indicates the interaction between theπbond of 3D-G and d orbitals in La_(0.2)CoFe_(1.8)O_(4).La_(0.2)CoFe_(1.8)/3D-G exhibits superior ORR performance(E_(1/2)=0.86 V vs.RHE)and OER performance(E_(j=10)=1.55 V vs.RHE)to CoFe_(2)O_(4)/3D-G(E_(1/2)=0.831 V vs.RHE,E_(j=10)=1.603 V vs.RHE).Furthermore,it demonstrates excellent bifunctional oxygen catalytic performance while maintaining high power density and stability in liquid zinc-air batteries(ZABs)and flexible ZABs(F-ZABs).This work presents a viable strategy for utilizing rare earth element doped spinels to enhance oxygen catalyst and ZABs performance.
文摘Three methods,isotopic tracing,fluorescence quenching and electrophysiological technique, are normally used to study transmernbrane transport. Planar lipid bilayer system is an electrophysiological method,in which artificial lipid and electrical measurement are used to simulate the ion-permeability of bio-membrane.It can
基金The work was supported by the National Natural Science Foundation of China(No.11925505).
文摘Recent progress in ultrafast lasers,ultrafast X-rays and ultrafast electron beams has made it possible to watch the motion of atoms in real time through pumpprobe technique.In this review,we focus on how the molecular dynamics can be studied with ultrafast electron diffraction where the dynamics is initiated by a pumping laser and then probed by pulsed electron beams.This technique allows one to track the molecular dynamics with femtosecond time resolution and Angstr6m spatial resolution.We present the basic physics and latest development of this technique.Representative applications of ultrafast electron diffraction in studies of laser-induced molecular dynamics are also discussed.This table-top technique is complementary to X-ray free-electron laser and we expect it to have a strong impact in studies of chemical dynamics.
