Optimizing the microdynamics in alkaline and neutral conditions is a significant but challenging task in developing pH-universal hydrogen evolution(HER)electrocatalysts.Herein,a unique Pt-O-Ni bridge has been construc...Optimizing the microdynamics in alkaline and neutral conditions is a significant but challenging task in developing pH-universal hydrogen evolution(HER)electrocatalysts.Herein,a unique Pt-O-Ni bridge has been constructed to alter the coordination and electronic environment between Pt nanoparticles(Pt_n)and nickel metaphosphate(NPO)substrate(Pt-NPO).Sufficient electron transfer from NPO to Pt_n to maintain an electron-rich environment and a low valence state of Pt_n.Furthermore,H*is produced from the H_(2)O dissociation on Ni site and then spillover toward Pt sites to bind into H_(2),which makes up for the insufficient H_(2)O dissociation ability of Pt in Volmer step.Pt-NPO exhibits long-term stability and only need the overpotentials of 22.3,33.0 and 30.5 mV to attain 10 mA cm^(-2)in alkaline,neutral and acidic media,respectively.The anion-exchange membrane(AEM)water electrolyzer catalyzed by Pt-NPO shows high water electrolysis performance that a cell voltage of 1.73 V is needed to obtain the current density of500 mA cm^(-2)in 1 M KOH at 80℃,at the same time maintains good stability for 350 h.The regulation strategy proposed in this work is helpful for the design and synthesis of highly efficient pH-universal HER electrocatalysts.展开更多
The dynamics of the H + NH→N + H<sub>2</sub> reaction has been investigated by means of the 3-atom model quasiclassical trajectory approach. The LEPS potential energy surface is employed in the study, whi...The dynamics of the H + NH→N + H<sub>2</sub> reaction has been investigated by means of the 3-atom model quasiclassical trajectory approach. The LEPS potential energy surface is employed in the study, which is obtained from the ab initio results and has an early saddle point in the minimum energy path. The results indicate that the reaction product H<sub>2</sub> is mainly scattered backward,and the reaction is found to occur via a direct channel. The product H<sub>2</sub> is in a cold excitation of rotational state, but has a hot vibrational excitation. Based on the potential surface and the trajectory analysis, the reaction mechanism has been explained successfully.展开更多
基金supported by the National Natural Science Foundation of China(22202080,22034006 and 22393930)Jilin Talent Development Foundation(E41S2001)the National Key Research and Development Program of China(2022YFF0710000).
文摘Optimizing the microdynamics in alkaline and neutral conditions is a significant but challenging task in developing pH-universal hydrogen evolution(HER)electrocatalysts.Herein,a unique Pt-O-Ni bridge has been constructed to alter the coordination and electronic environment between Pt nanoparticles(Pt_n)and nickel metaphosphate(NPO)substrate(Pt-NPO).Sufficient electron transfer from NPO to Pt_n to maintain an electron-rich environment and a low valence state of Pt_n.Furthermore,H*is produced from the H_(2)O dissociation on Ni site and then spillover toward Pt sites to bind into H_(2),which makes up for the insufficient H_(2)O dissociation ability of Pt in Volmer step.Pt-NPO exhibits long-term stability and only need the overpotentials of 22.3,33.0 and 30.5 mV to attain 10 mA cm^(-2)in alkaline,neutral and acidic media,respectively.The anion-exchange membrane(AEM)water electrolyzer catalyzed by Pt-NPO shows high water electrolysis performance that a cell voltage of 1.73 V is needed to obtain the current density of500 mA cm^(-2)in 1 M KOH at 80℃,at the same time maintains good stability for 350 h.The regulation strategy proposed in this work is helpful for the design and synthesis of highly efficient pH-universal HER electrocatalysts.
文摘The dynamics of the H + NH→N + H<sub>2</sub> reaction has been investigated by means of the 3-atom model quasiclassical trajectory approach. The LEPS potential energy surface is employed in the study, which is obtained from the ab initio results and has an early saddle point in the minimum energy path. The results indicate that the reaction product H<sub>2</sub> is mainly scattered backward,and the reaction is found to occur via a direct channel. The product H<sub>2</sub> is in a cold excitation of rotational state, but has a hot vibrational excitation. Based on the potential surface and the trajectory analysis, the reaction mechanism has been explained successfully.
