Bicomponent CuO/NiCo2O4 nanocomposites for the dehydrogenation of ammonia borane and the tandem hydrogenation of halogenated nitroaromatics

Abstract

Nonnoble bicomponent NiCo-based nanocomposites (CuO/NiCo₂O₄) were prepared by the coprecipitation–calcination method and characterized. Furthermore, the catalytic performance of CuO/NiCo₂O₄ nanocomposites was investigated in the hydrolytic dehydrogenation of ammonia borane (AB) and tandem hydrogenation of halogenated nitroaromatics. The results show that the CuO/NiCo₂O₄ nanocomposites have good activity in the tandem hydrogenation of two chloronitrobenzenes (m-CNB, o-CNB), achieving 100% yield of m- and o-chloroaniline (m-CAN, o-CAN) under mild conditions. High turnover frequency (TOF = 296.3 h⁻¹) was achieved for CuO/NiCo₂O₄. With respect to bromo- or iodonitrobenzenes, CuO/NiCo₂O₄ displayed moderate or low selectivity, especially for iodonitrobenzenes with complete hydrodeiodination. Noteworthily, the CuO/NiCo₂O₄ nanocomposite exhibits remarkable recyclability and can be used continuously for more than 11 times without deactivation.