Rapid synthesis of AgCu bimetallic nanodendrites with enhanced catalytic activity for 4-nitrophenol reduction

Herein, AgCu nanodendrites were fabricated via a facile one-step displacement reaction at ambient temperature with Zn powder as the reducing agent. The morphology, structure, and composition of the products were systematically characterized by transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The results demonstrate that the structure and morphology of the catalysts are strongly dependent on the Ag/Cu molar ratio. The catalytic performance was evaluated by the reduction of 4-nitrophenol (4-NP) at room temperature, in comparison with monometallic Ag and Cu catalysts. The catalytic activity follows the order Ag1Cu1 > Ag1Cu3 > Ag3Cu1 > Ag > Cu. The optimized Ag1Cu1 catalyst achieves 98.6% 4-NP conversion within 341 s, which is significantly faster than monometallic Ag (98.5% in 566 s) and Cu (98.8% in 1608 s). Moreover, the Ag1Cu1 catalyst retains 87% conversion after five consecutive cycles, showing good stability and reusability. The unique aggregated dendritic structure not only leads to composition-dependent catalytic activity but also facilitates catalyst separation from the reaction system. This work provides a simple and efficient strategy for constructing bimetallic nanodendrites and offers promising prospects for environmental remediation of wastewater containing 4-NP.