Highly efficient catalyst nickel‐cobalt‐silver for ultrasound‐assisted degradation of 4‐nitrophenol and hydrodechlorination of chlorophenols

Abstract Industrial wastewater containing hazardous organic compounds has contributed to a growing problem of water pollution, posing a significant threat to the ecological environment. Unfortunately, conventional methods for treating these organic pollutants are often ineffective or have notable limitations. Meanwhile, nanocatalysts have garnered considerable attention due to their exceptional properties, enhancing reaction rates and selectivity. In this research, various techniques such as X‐ray diffraction (XRD), scanning electron microscopy with energy dispersive X‐ray (SEM‐EDX), transmission electron microscopy (TEM), and Brunauer–Emmett–Teller (BET) method were used to characterize the synthesized nickel‐cobalt‐silver nanocatalyst. The catalyst underwent testing for activity in the degradation of 4‐nitrophenol (4‐NP), as well as the influence of temperature, time, and catalyst content were carried out. The results revealed an average catalytic activity with a 10% catalyst loading of NiCoAg/C, corresponding to a 4‐NP conversion of 58% within 6 h. Remarkably, ultrasound‐assisted reaction achieved over 94% conversion of 4‐NP in 2 min at room temperature, however, its stability declined notably after five cycles. Additionally, the catalytic performance was assessed in the hydrodechlorination (HDC) of chlorophenols, resulting in approximately 60% conversion of 2‐chorophenol (2‐CP) and 4‐chorophenol (4‐CP) within 180 min at room temperature. Notably, with ultrasonic assistance, the HDC reaction achieved a conversion efficiency of nearly 80% in just 50 min.