Vacancy-enhanced Mo-N_(2) interaction in MoSe_(2) nanosheets enables efficient electrocatalytic NH_(3) synthesis

摘要

NH_(3) plays an essential role in human life since it is an important raw material for fertilizers,plastics and rubbers production.As an NH_(3) synthesis technology under ambient conditions,electrocatalytic N_(2) reduction reaction(NRR)has great potential to replace the energy-intensive Haber-Bosch process.The key of electrocatalytic NRR is the exploration of efficient catalysts.Transition metal Mo is promising since it exists naturally in nitrogenase due to the unique Mo-N_(2) interaction;particularly in the form of 2D material such as MoSe_(2),the surface area is maximized for more active sites.However,the NRR performance of MoSe_(2) is still unsatisfactory because Mo is only exposed at the semi-open edge,and the electronegative Se-mantled surface area remains inaccessible to N_(2).Herein,we propose a simple and effective strategy to create high-concentration Se vacancies in MoSe_(2) through heteroatom doping induced lattice strain,which effectively enhances the Mo-N_(2) interaction on the surface area.In result,high NH_(3) yield(3.04×10^(–10)mol s^(–1)cm^(–2))and Faraday efficiency(21.61%)are attained at–0.45 V vs.RHE in 0.1 mol/L Na_(2)SO_(4).