Green synthesis of zerovalent copper nanoparticle (Cu-GT NPs) has been introduced and compared with the physico-chemical properties of chemically produced zerovalent copper (ZVC) nanoparticle. Herein, we demonstrate the catalytic ability of both Cu-GT-NPs and sodium borohydride synthesized ZVC (Cu-SB) towards the degradation of 2,4-dichlorophenol (2,4-DCP). Green tea extract was also used to reduce and stabilize the as-synthesized copper nanoparticles. The surface and particle size of Cu-GT-NPs and Cu-SB were characterized and compared by transmission electron microscopy (TEM) and dynamic light scattering (DLS) which were found to be 10 ± 5 and 200 ± 20 nm, respectively. Cu-GT NPs and Cu-SB particles were further analyzed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy to confirm the possible crystallization and chemical environment. The degradation efficiency was optimized for the most suitable pollutant concentration. Highest degradation efficiency was recorded during 5 days reaction (incubation time) with kinetic rate constant of 0.697 min− 1 g− 1, when pollutant concentration was under 7.5 ppm, with catalyst dose of 2 g L− 1, pH = 6.2 and the 25 °C reaction temperature. The activation energy of 29.65 kJ mol− 1 was calculated for feasible 2,4-DCP degradation by Cu-SB particles in this study. These research findings help to understand the differences in characteristics and the degradation ability of copper nanoparticles synthesized by different methods and also paves the way to synthesize low-cost and environmentally friendly metal nanomaterials.