Nanoscale zero-valent iron particles modified on reduced graphene oxides using a plasma technique for Cd(II) removal

Abstract

Nanoscale zero-valent iron particles supported on reduced graphene oxides (NZVI/rGOs) from spent graphene oxide (GO)-bound iron ions were developed by using a plasma reduction method to improve the reactivity and stability of NZVI. The specific surface area (SSA) of NZVI/rGOs was 117.97 m2 g−1, while the SSA of NZVI particles was 59.59 m2 g−1. The adsorption kinetics was quite fast, which could be completed within 50 min. The adsorption capacity of NZVI/rGOs toward Cd(II) was 425.72 mg g−1, which was higher than other adsorbent materials. Moreover, the NZVI/rGOs could be regenerated by the plasma reduction technique and maintained high removal performance after four cycles. NZVI/rGOs also showed high removal capability toward Cd(II) in the simulated Cd(II)-bearing effluent. The above experimental results show that the NZVI/rGO can be efficient materials for the purification of Cd(II)-contaminated water in the environmental pollution management.