The Fe–N–C material is a promising non-noblemetal electrocatalyst for oxygen reduction reaction(ORR).Further improvement on the ORR activity is highly desired in order to replace Pt/C in acidic media.Herein,we devel...The Fe–N–C material is a promising non-noblemetal electrocatalyst for oxygen reduction reaction(ORR).Further improvement on the ORR activity is highly desired in order to replace Pt/C in acidic media.Herein,we developed a new-type of single-atom Fe–N–C electrocatalyst,in which Fe–Nxactive sites were modified by P atoms.The half-wave potential of the optimized material reached 0.858 V,which is 23 mV higher than that of the pristine one in a 0.1 mol L-1 HClO4 solution.Density functional theory(DFT)calculations revealed that P-doping can reduce the thermodynamic overpotential of the rate determining step and consequently improve the ORR activity.展开更多
Single-atom catalyst(SAC)is one of the newest catalysts,and attracts people’s wide attention in cancer therapy based on their characteristics of maximum specific catalytic activity and high stability.We designed and ...Single-atom catalyst(SAC)is one of the newest catalysts,and attracts people’s wide attention in cancer therapy based on their characteristics of maximum specific catalytic activity and high stability.We designed and synthesized a Fe-N decorated graphene nanosheet(Fe-N5/GN SAC)with the coordination number of five.Through enzymology and theoretical calculations,the Fe-N5/GN SAC has outstanding intrinsic peroxidase-like catalytic activity due to single-atom Fe site with five-N-coordination structure.We explored its potential on lung cancer therapy,and found that it could kill human lung adenocarcinoma cells(A549)by decomposing hydrogen peroxide(H_(2)O_(2))into toxic reactive oxygen species(ROS)under acidic microenvironment in threedimensional(3D)lung cancer cell model.Our study demonstrates a promising application of SAC with highly efficient single-atom catalytic sites for cancer treatment.展开更多
The enzyme-mimicking catalytic activity of single-atom nanozymes has been widely used in tumor treatment.However,research on alleviating metabolic diseases,such as hyperglycemia,has not been reported.Herein,we found t...The enzyme-mimicking catalytic activity of single-atom nanozymes has been widely used in tumor treatment.However,research on alleviating metabolic diseases,such as hyperglycemia,has not been reported.Herein,we found that the single-atom Ce-N_(4)-C-(OH)_(2)(SACe-N_(4)-C-(OH)_(2))nanozyme promoted glucose absorption in lysosomes,resulting in increased reactive oxygen species production in HepG2 cells.Furthermore,the SACe-N_(4)-C-(OH)_(2)nanozyme initiated a cascade reaction involving superoxide dismutase-,oxidase-,catalase-,and peroxidase-like activity to overcome the limitations associated with the substrate and produce•OH,thus improving glucose intolerance and insulin resistance by increasing the phosphorylation of protein kinase B and glycogen synthase kinase 3β,and the expression of glycogen synthase,promoting glycogen synthesis to improve glucose intolerance and insulin resistance in high-fat diet-induced hyperglycemic mice.Altogether,these results demonstrated that the novel nanozyme SACeN_(4)-C-(OH)_(2)alleviated the effects of hyperglycemia without evident toxicity,demonstrating its excellent clinical application potential.展开更多
基金This work was supported by the National Key R&D Program of China(2017YFB0102900)the Research Grant Council(N一HKUST610/17)of Hong Kong Special Administrative Region.It used resources of the Advanced Photon Source,Office of Science user facilities,supported by the U.S.Department of Energy,Office of Science,Office of Basic Energy Sciences(DE-AC02-06CH11357).
文摘The Fe–N–C material is a promising non-noblemetal electrocatalyst for oxygen reduction reaction(ORR).Further improvement on the ORR activity is highly desired in order to replace Pt/C in acidic media.Herein,we developed a new-type of single-atom Fe–N–C electrocatalyst,in which Fe–Nxactive sites were modified by P atoms.The half-wave potential of the optimized material reached 0.858 V,which is 23 mV higher than that of the pristine one in a 0.1 mol L-1 HClO4 solution.Density functional theory(DFT)calculations revealed that P-doping can reduce the thermodynamic overpotential of the rate determining step and consequently improve the ORR activity.
基金N.C.would like to acknowledge the support the 2115 Talent Development Program of China Agricultural UniversityThis research used resources of the Advanced Photon Source,a U.S.Department of Energy(DOE)Office of Science User Facility,operated for the DOE Office of Science by Argonne National Laboratory under Contract No.DE-AC02-06CH11357.
文摘Single-atom catalyst(SAC)is one of the newest catalysts,and attracts people’s wide attention in cancer therapy based on their characteristics of maximum specific catalytic activity and high stability.We designed and synthesized a Fe-N decorated graphene nanosheet(Fe-N5/GN SAC)with the coordination number of five.Through enzymology and theoretical calculations,the Fe-N5/GN SAC has outstanding intrinsic peroxidase-like catalytic activity due to single-atom Fe site with five-N-coordination structure.We explored its potential on lung cancer therapy,and found that it could kill human lung adenocarcinoma cells(A549)by decomposing hydrogen peroxide(H_(2)O_(2))into toxic reactive oxygen species(ROS)under acidic microenvironment in threedimensional(3D)lung cancer cell model.Our study demonstrates a promising application of SAC with highly efficient single-atom catalytic sites for cancer treatment.
基金This work was supported by the Natural Science Foundation of China(Grant No.32001787)the 2115 Talent Development Program of China Agricultural University。
文摘The enzyme-mimicking catalytic activity of single-atom nanozymes has been widely used in tumor treatment.However,research on alleviating metabolic diseases,such as hyperglycemia,has not been reported.Herein,we found that the single-atom Ce-N_(4)-C-(OH)_(2)(SACe-N_(4)-C-(OH)_(2))nanozyme promoted glucose absorption in lysosomes,resulting in increased reactive oxygen species production in HepG2 cells.Furthermore,the SACe-N_(4)-C-(OH)_(2)nanozyme initiated a cascade reaction involving superoxide dismutase-,oxidase-,catalase-,and peroxidase-like activity to overcome the limitations associated with the substrate and produce•OH,thus improving glucose intolerance and insulin resistance by increasing the phosphorylation of protein kinase B and glycogen synthase kinase 3β,and the expression of glycogen synthase,promoting glycogen synthesis to improve glucose intolerance and insulin resistance in high-fat diet-induced hyperglycemic mice.Altogether,these results demonstrated that the novel nanozyme SACeN_(4)-C-(OH)_(2)alleviated the effects of hyperglycemia without evident toxicity,demonstrating its excellent clinical application potential.
