Porous Composites Embedded With Cu and Co Nanoparticles for Efficient Catalytic Reduction of 4-Nitrophenol

The preparation of catalytically active composites consisting of a porous support and metal nanocatalysts is vital for the development of efficient catalytic systems. In particular, the development of porous composites containing inexpensive metal nanocatalysts instead of expensive noble metals is of great importance. Herein, we report the preparation of porous composites consisting of porous carbon (PC) or a zeolitic imidazolate framework (ZIF) as a support material, along with inexpensive Cu and Co as nanocatalysts. A composite of ZIF-67 and metallic Cu nanoparticles (Cu@ZIF-67) was produced from the simple thermal treatment of Cu²⁺-incorporating ZIF-67 (ZIF-67/Cu²⁺) at 450°C. However, the high-temperature pyrolysis of ZIF-67/Cu²⁺ at 800°C resulted in a PC-based composite containing metallic Cu and Co nanoparticles (Cu,Co@PC). The resulting Cu@ZIF-67 and Cu,Co@PC samples exhibited efficient catalytic activity for the reduction of 4-nitrophenol to 4-aminophenol.