Cu-MOF derived two-dimensional copper-carbon nanosheets for efficient nitrate reduction

Abstract

In recent years, the strategy of reducing ammonia (NH3) from nitrate-related sources such as industrial wastewater driven by clean energy sources has garnered significant attention. Previous studies have shown that Cu-based species can effectively catalyze nitrate reduction reaction (NO3RR), but the reaction intermediates tend to aggregate on the surface of catalysts, resulting in low Faraday efficiency. In this study, two-dimensional porous carbon nanosheets were successfully prepared through direct pyrolysis of a mixture of ZnCu-BTC crystal and FeCl3 salt. Interestingly, cube-shaped CuCl nanoparticles were easily precipitated from the MOF-derived carbon surface during acid etching process. The resulting CuCl-CNS exhibited good NO3RR performance, achieving an NH3 yield of 96.9% and 292.5 µmol h-1 cm-2 at -0.60V versus reversible hydrogen electrode. Moreover, the assembled zinc-nitrate battery revealed a peak power density of 4.73mWcm-2 and long-term cycle stability. This work provides valuable insights into the development of MOF-derived Cu-based nanocomposites for effective nitrate reduction.