Insight into the Morphology‐Dependent Catalytic Performance of CuO/CeO₂ Produced by Tannic Acid for Efficient Hydrogenation of 4‐Nitrophenol

Abstract

The construction of a heterogeneous nanocatalyst with outstanding catalytic performance via an environmentally benign and cost‐effective synthetic category has long been one of the challenges in nanotechnology. Herein, we synthesized highly efficient and low‐cost mesoporous morphology‐dependent CuO/CeO2‐Rods and CuO/CeO2‐Cubes catalysts by employing a green and multifunctional polyphenolic compound (tannic acid) as the stabilizer and chelating agent for 4‐nitrophenol (4‐NP) reduction reaction. The CuO/CeO2‐Rods exhibited excellent performance, of which the activity was 3.2 times higher than that of CuO/CeO2‐Cubes. This can be connected with the higher density of oxygen vacancy on CeO2‐Rods (110) than CeO2‐Cubes (100), the oxygen vacancy favors anchoring CuO species on the CeO2 support, which promotes the strong interaction between finely dispersed CuO and CeO2‐Rods at the interfacial positions and facilitates the electron transfer from BH4− to 4‐NP. The synergistic catalytic mechanism illustrated that 4‐NP molecules preferentially adsorbed on the CeO2, while H2 from BH4− dissociated over CuO to form highly active H* species, contributing to achieving efficient hydrogenation of 4‐NP. This study is expected to shed light on designing and synthesizing cost‐effective and high‐performance nanocatalysts through a greener synthetic method for the areas of catalysis, nanomaterial science and engineering, and chemical synthesis.

Structure engineering of CeO2for boosting the Au/CeO2nanocatalyst in the green and selective hydrogenation of nitrobenzene

“…Based on our previous work, 61 the catalytic hydrogenation of 4-nitrophenol (4-NP) was studied as a model reaction to screen the Au/CeO 2 catalysts because of its simple operation steps. 62 Fig.…”