Controllable synthesis of sea urchin-like Cu–Au bimetallic nanospheres and their utility as efficient catalyst for hydrogenation of 4-nitrophenol

4-nitrophenol (4-NP) is a harmful aromatic compound to environment. The catalytic hydrogenation of 4-NP was considered as a profitable approach due to the valuable organic intermediate product. High efficiency catalysts are crucial. Herein, Cu–Au bimetallic nanospheres (BNSs) with sea urchin structure were fabricated by tuning the reaction condition and ratio of precursors. The Cu–Au BNSs exhibited effective catalytic activity in the reduction of 4-NP and K3[Fe(CN)6]. The optimum catalyst can be determined as the Cu–Au BNSs prepared by 15 ​mL AA, 4-NP can be reduced to 4-AP in 150 ​s ​(k ​= ​3.02 ​× ​10−2 s−1) with TOF value of 0.149 (s−1). The reusability of Cu–Au BNSs was evaluated with high effectiveness, the catalytic activity remained negligible loss over 18 cycles with efficiency over 95%, indicated their good reusability, which can be attributed to the synergistic effect of Cu–Au BNSs. The fabrication of bimetallic nanostructures provided an efficient approach to design efficient catalyst. The process of synthesis and their catalytic performance of Cu–Au BNSs. [Display omitted] •The sea urchin-like bimetallic Cu–Au BNSs were fabricated by tuning the reductant.•Cu–Au BNSs exhibited effective catalytic activity and good reusability in the reduction of 4-NP.•The small-sized Cu–Au BNSs had excellent catalytic performance.•Cu–Au BNSs can be cycled for at least 18 times without loss of catalytic performance.