The Preparation of UiO-66-NH2/CNT Electrocatalyst and its High Catalytic Performance for Electrochemical Synthetic Ammonia in Neutral Electrolyte

摘要

The electrochemical synthesis of ammonia is a sustainable green ammonia synthesis technology.The core reaction involved in this process-the nitrogen reduction reaction(NRR)is a slow kinetic reaction,which requires efficient catalysts to improve the ammonia yield rate.A series of UiO-66-NH2/CNT-X(X=0.05,0.10,0.15,0.20 g)electrocatalysts with different carbon nanotube(CNT)content were synthesized by hydrothermal method.UiO-66-NH2/CNT-0.15 with appropriate CNT content has the highest NH3 yield of 1.85×10~(-10)molcm~(-2)s~(-1)(22.644 μgh~(-1)mg_(cat)~(-1))at-0.3 V(vs.RHE),and the Faradaic efficiency(FE)is 37.78%.The main reason is that the conductivity of CNT improves the charge transfer efficiency and ensures the effective electron conduction path of the catalyst.Besides,CNT in UiO-66-NH2/CNT-X composite material inhibits the aggregation of UiO-66-NH2 particles,exposes more active sites and reduces the particle size of UiO-66-NH2.So,the synergistic effect between UiO-66-NH2 particles and CNT improves the ammonia yield.