ZIF-67 derived Ni50Co50-layered double hydroxide nanoflower used for efficient reduction of low-concentration nitric oxide conversion

The mechanism for the NORR performance differences of varying Ni/Co ratios in Ni x Co y -LDH NF was revealed. • Ni 50 Co 50 -LDH NF can achieve a maximum NH 3 yield rate of 22.8 mg h −1 cm −2 with extremely low concentration NO. • We realized the efficient extraction and valorization of the produced ammonia. Utilizing electrocatalytic methods to efficiently convert harmful nitric oxide into derivatives of ammonia is undoubtedly a very economical way. Herein, we synthesized a series of different metal ratio Ni x Co y -layered double hydroxide nanoflower (Ni x Co y -LDH NF) material derived from the metal-organic framework (MOF), which can convert low concentration NO into ammonia. Among them, Ni 50 Co 50 -layered double hydroxide nanoflower can achieve a NH 3 yield rate of 4.33 mg h −1 cm −2 with a Faradaic efficiency of 74.6% in a H-cell. Notably, the yield can increase to 22.8 mg h −1 cm −2 at −0.4 V (V vs.RHE) with a current density over 250 mA cm −2 in a gas diffusion electrode. The post-electrolysis electrolyte was then collected and a membrane permeation device was used to purify the free ammonia into ammonium chloride. Our work investigated the influence of different proportions of Ni on the nitric oxide reduction reaction performance of layered double hydroxide materials and provided a new strategy for efficient NO conversion catalyst design. Download: Download high-res image (87KB) Download: Download full-size image