Enhanced photocatalytic degradation of sulfamethoxazole by stable hierarchical Fe2O3/Co3O4 heterojunction on nickel foam

A facile approach was successfully employed to prepare Fe 2 O 3 /Co 3 O 4 nanosheet arrays on nickel foams (Fe 2 O 3 /Co 3 O 4 @NF), which owned such advantages as narrow band gap energies and high separation rate of photoexcited electron-hole pairs. The combination of Fe 2 O 3 and Co 3 O 4 dramatically enhanced the photocatalytic activity towards sulfamethoxazole (SMZ) degradation, with the highest catalytic efficiency of k = 0.0538 min −1 , which was much higher than that of Fe 2 O 3 @NF (0.0098 min −1 ) and Co 3 O 4 @NF (0.0094 min −1 ). The introduction of Ni foam could not only act as the support to anchor photocatalyst, but also work as the electron mediator to promote the transition of electron-hole pairs. Reactive species trapping experiments combined with electron paramagnetic resonance analysis confirmed • O 2 − was primarily responsible for SMZ degradation. Furthermore, Fe 2 O 3 /Co 3 O 4 @NF was effective and almost unaffected by inorganic cations and anions in aqueous solution. This study could provide a facile and promising path for the construction of self-supported metal oxide-based heterojunction with high efficiency and strong stability. Fe 2 O 3 and Co 3 O 4 nanosheet arrays were incorporated into a Z-scheme heterojunction and loaded on the Ni foam. The prepared Fe 2 O 3 /Co 3 O 4 @NF exhibited superior activities towards sulfamethoxazole degradation under simulated solar light irradiation.