Novel honeycomb-like metal organic frameworks as multifunction electrodes for nitrate degradation: A computational study

Abstract

Electrocatalytic reduction of ubiquitous waste nitrate to ammonia (NH3) is a promising converting route toward recovering the disrupted nitrogen cycle. However, this carbon neutral synthesis process suffers from sluggish kinetics and flat Faradaic efficiency owing to the lack of efficient catalysts. Herein, we reported a novel two-dimension metal organic framework (MOF) as multifunction electrode via combining metal Zr atoms and benzenehexaselenolate skeletons (denoted as Zr-BHS) for nitrate remediation, featured with an impressive limiting potential of – 0.47 V, satisfactory selectivity, and favorable stability. A reasonable electronic indicator φ proposed here successfully explains why early transition metal elements in recently reports exhibit excellent electrochemical nitrate reduction activity. More importantly, as a derivative, Co-BHT has surprisingly superior hydrogen evolution performance comparable to the Pt-based material since the striking H-s and Co-d orbital hybridization overlap tailors the H attachment. Our studies not only offer a brand new multifunction MOF material for hydrogen energy carrier (NH3 and H2) electroreduction, but also put forward an ingenious self-assembly tactic, paving road for guiding the top-down synthesis.