Copper selenides controlled hydrothermal synthesis of porous micro-networks with highly efficient photocatalysis

Hybrid photocatalysts have important prospects in clean energy and sewage treatment. Herein, we construct functional hybrid materials consisting of nonstoichiometric copper selenides (Cu2-xSe) and porous gadolinium micro-networks (P-MNs) formed by the hydrothermal treatment of gadolinium (III) nitrate and citric acid (Cu2-xSe/P-MNs) as the excellent photocatalyst for the photodegradation of fluorescent dyes. Cu2-xSe/P-MNs photocatalysts show good chemical stability because the hybridization of Cu2-xSe and P-MNs is based on an in-situ growth strategy. More importantly, due to the strong light-harvesting and good electron transfer ability, Cu2-xSe/P-MNs show superior photocatalytic activity with a catalytic rate of up to 0.33 min−1 only under the irradiation of 20 W of low-power white light, which is at least two orders of magnitude higher than other common photocatalysts. Detailed studies show that the h+, O2•−, and ⋅OH are the main active species in the photocatalytic process. According to the ‘three channel’ catalytic path, rhodamine 6G as the model dye can be completely and rapidly degraded within 15 min. Because of the good photocatalytic activity, Cu2-xSe/P-MNs show great application prospects.