The development of effective uranium-removal techniques is of great significance to the environment and human health.In this work,a double potential step technique(DPST)was applied to remove U(VI)from uranium-containi...The development of effective uranium-removal techniques is of great significance to the environment and human health.In this work,a double potential step technique(DPST)was applied to remove U(VI)from uranium-containing wastewater using a carbon felt electrode modified by graphene oxide/phytic acid composite(GO-PA@CF).The application of DPST can inhibit water splitting and prevent GO-PA from adsorbing other interfering ions in wastewater.The GO-PA composite can effectively accelerate the electrochemical reduction rate of U(VI),which significantly improved the electrochemical deposition rate of uranium oxide.As a result,the maximum removal efficiency and maximum removal capacity of GOPA@CF electrode reached 98.7%and 1149.3 mg/g,respectively.The removal efficiency remained 97.2%after five cycles of reuse.Moreover,the removal efficiency of GO-PA@CF electrode can reach more than 70%in simulated wastewater.展开更多
The nitrogen reduction reaction(NRR)under ambient conditions is still challenging due to the inertness of N2.Herein,we report a series of superior NRR catalysts identified by examining Ti2NO2 MXenes embedded with 28 d...The nitrogen reduction reaction(NRR)under ambient conditions is still challenging due to the inertness of N2.Herein,we report a series of superior NRR catalysts identified by examining Ti2NO2 MXenes embedded with 28 different single-atom catalysts using first-principles calculations.The stability of this system was first verified using formation energies,and it is discovered that N2 can be effectively adsorbed due to the synergistic effect between single atom catalysis and the Ti atoms.Examination of the electronic structure demonstrated that this design satisfies orbital symmetry matching where“acceptor-donor”interaction scenario can be realized.A new“enzymatic-distal”reaction mechanism that is a mixture of the enzymatic and distal pathways was also discovered.Among all of the candidates,Ni anchored on MXene system achieves an onset potential as low as–0.13 V,which to the best of our knowledge is the lowest onset potential value reported to date.This work elucidates the significance of orbital symmetry matching and provides theoretical guidance for future studies.展开更多
Methanol oxidation on smooth Pt electrode modified with different coverage of Ru was studied using cyclic voltammetry and potential step combined with differential electrochemical mass spectroscopy. The current effici...Methanol oxidation on smooth Pt electrode modified with different coverage of Ru was studied using cyclic voltammetry and potential step combined with differential electrochemical mass spectroscopy. The current efficiency of formed CO 2 was calculated from faraday current and ion current of m/z =44. The results show that Ru modified Pt electrode with the coverage of ca . 0 3 has the highest catalytic activity for methanol electrooxidation, i.e. faraday current and the current efficiency of CO 2 at the low potentials reach to the maximum. In addition, Ru loses its co catalytic properties at the high potentials.展开更多
Gold film (~50 nm) serves as the working electrode to allow the electrochemical process to be monitored using surface plasmon resonance (SPR) technology. The extracted precise value of time resolved SPR signal pertur...Gold film (~50 nm) serves as the working electrode to allow the electrochemical process to be monitored using surface plasmon resonance (SPR) technology. The extracted precise value of time resolved SPR signal perturbed by the non-faradic potential was investigated to study the response time of gold film under potential application. A qualitative model of the reflection and transmission spectra of gold film working as the electrochemical interface is presented. The correlation between three parameters, including thickness of gold film, incident angle and wavelength of beam, were analyzed to generate an optimized configuration for gold film to detect potential. These results emphasis the efficiency of SPR technique used as a diagnostic tool for the electrochemical process.展开更多
基金the financial support of the National Natural Science Foundation of China(Nos.41361088 and41867063)。
文摘The development of effective uranium-removal techniques is of great significance to the environment and human health.In this work,a double potential step technique(DPST)was applied to remove U(VI)from uranium-containing wastewater using a carbon felt electrode modified by graphene oxide/phytic acid composite(GO-PA@CF).The application of DPST can inhibit water splitting and prevent GO-PA from adsorbing other interfering ions in wastewater.The GO-PA composite can effectively accelerate the electrochemical reduction rate of U(VI),which significantly improved the electrochemical deposition rate of uranium oxide.As a result,the maximum removal efficiency and maximum removal capacity of GOPA@CF electrode reached 98.7%and 1149.3 mg/g,respectively.The removal efficiency remained 97.2%after five cycles of reuse.Moreover,the removal efficiency of GO-PA@CF electrode can reach more than 70%in simulated wastewater.
文摘The nitrogen reduction reaction(NRR)under ambient conditions is still challenging due to the inertness of N2.Herein,we report a series of superior NRR catalysts identified by examining Ti2NO2 MXenes embedded with 28 different single-atom catalysts using first-principles calculations.The stability of this system was first verified using formation energies,and it is discovered that N2 can be effectively adsorbed due to the synergistic effect between single atom catalysis and the Ti atoms.Examination of the electronic structure demonstrated that this design satisfies orbital symmetry matching where“acceptor-donor”interaction scenario can be realized.A new“enzymatic-distal”reaction mechanism that is a mixture of the enzymatic and distal pathways was also discovered.Among all of the candidates,Ni anchored on MXene system achieves an onset potential as low as–0.13 V,which to the best of our knowledge is the lowest onset potential value reported to date.This work elucidates the significance of orbital symmetry matching and provides theoretical guidance for future studies.
文摘Methanol oxidation on smooth Pt electrode modified with different coverage of Ru was studied using cyclic voltammetry and potential step combined with differential electrochemical mass spectroscopy. The current efficiency of formed CO 2 was calculated from faraday current and ion current of m/z =44. The results show that Ru modified Pt electrode with the coverage of ca . 0 3 has the highest catalytic activity for methanol electrooxidation, i.e. faraday current and the current efficiency of CO 2 at the low potentials reach to the maximum. In addition, Ru loses its co catalytic properties at the high potentials.
基金European Union STREP project (Grant No. NMP4-CT-2006-031971)Chongqing Science and Technology Research Fund (Grant No. cstc2011ggB0015)the West Light Foundation of Chinese Academy of Sciences
文摘Gold film (~50 nm) serves as the working electrode to allow the electrochemical process to be monitored using surface plasmon resonance (SPR) technology. The extracted precise value of time resolved SPR signal perturbed by the non-faradic potential was investigated to study the response time of gold film under potential application. A qualitative model of the reflection and transmission spectra of gold film working as the electrochemical interface is presented. The correlation between three parameters, including thickness of gold film, incident angle and wavelength of beam, were analyzed to generate an optimized configuration for gold film to detect potential. These results emphasis the efficiency of SPR technique used as a diagnostic tool for the electrochemical process.