Synthesis of bifunctional non-noble monolithic catalyst Co-W-P/carbon cloth for sodium borohydride hydrolysis and reduction of 4-nitrophenol

Abstract

Amorphous Co-W-P catalysts, which were prepared on carbon cloth (CC) by electrodeposition, have been investigated as bifunctional non-noble catalysts for the hydrogen generation from alkaline NaBH4 solution and the reduction of 4-nitrophenol by NaBH4. Scanning electron microscopes (SEM), energy dispersive X-ray spectrometer (EDX), and X-ray diffraction (XRD) were used to characterize the Co-W-P/CC catalysts. The hydrogen generated catalytic properties of as-prepared catalysts with different content of P and the stability were investigated in the alkaline NaBH4 solution of 5 wt% NaBH4 and 2 wt% NaOH. The activation energy for hydrolysis of NaBH4 by the Co-W-P catalyst was also probed at different temperature, and the results show that the obtained Co-W-P/CC catalysts exhibit very low apparent active energy (Ea = 27.18 kJ mol−1). Finally, we detect the catalytic activity of Co-W-P/CC in the reduction of 4-nitrophenol for the first time, and it also presents outstanding catalytic capability with the apparent rate constant (kapp) of 11.91 × 10−3 s−1. These characteristics indicate that the Co-W-P/CC catalysts possess a potential application on both the sodium borohydride hydrolysis and reduction of 4-nitrophenol.