Boosting oxygen evolution reactivity by modulating electronic structure and honeycomb-like architecture in Ni_(2)P/N,P-codoped carbon hybrids

Oxygen evolution reaction(OER)as the foremost stumbling block to generate cost-effective clean fuels has received extensive attention in recent years.But,it still maintains the challenge to manipulate the geometric and electronic structure during single reaction process under the same conditions.Herein,we report a simple self-template strategy to generate honeycomb-like Ni_(2)P/N,P-C hybrids with preferred electronic architecture.Experiments coupled with theoretical results revealed that the synthesized catalyst has two characteristics:firstly,the unique honeycomb-like morphology not only enables the fully utilization of catalytic active sites but also optimizes the mass/electron transportation pathway,which favor the diffusion of electrolyte to accessible active sites.Secondly,N,P-C substrate,on the one hand,largely contributes the electronic distribution near Fermi level(E_(F))thus boosting its electrical conductivity.On the other hand,the support effect result in the upshift of d-band center and electropositivity of Ni sites,which attenuates the energy barrier for the adsorption of OH~àand the formation of*OOH.In consequence,the optimized Ni_(2)P/N,P-C catalysts feature high electrocatalytic activity towards OER(a low overpotential of 252 m V to achieve10 m A cm^(-2))and 10 h long-term stability,the outstanding performance is comparable to most of transition metal catalysts.This work gives a innovative tactics for contriving original OER electrocatalysts,inspirng deeper understanding of fabricating catalysts by combining theoretical simulation and experiment design.

Highly efficient electrochemically driven water oxidation by graphenesupported mixed-valent Mn_(16)-containing polyoxometalate

A highly efficient catalyst of graphene-supported mixed-valent Mn_(16)-containing polyoxometalate is reported here by electrochemical strategy. The modified electrode with the catalyst exhibits an excellent electrocatalytic performance for water oxidation, which will contribute to the development of highly efficient catalysts for oxygen evolution.

Blind zone-suppressed hybrid beam steering for solid-state Lidar

We demonstrate a blind zone-suppressed and flash-emitting solid-state Lidar based on lens-assisted beam-steering technology.As a proof-of-concept demonstration,with the design of a subwavelength-gap 1D long-emitter array and multiwavelength flash beam emitting,the device was measured to have 5%blind zone suppression,0.06°/point-deflection step,and 4.2μs scanning speed.In time-of-flight ranging experiments,Lidar systems have a field of view of 11.3°×8.1°(normal device)or 0.9°×8.1°(blind-zone suppressed device),far-field number of resolved points of 192,and a detection distance of 10 m.This work demonstrates the possibility that a new integrated beam-steering technology can be implemented in a Lidar without sacrificing other performance.