A facile in situ fabrication and visible-light-response photocatalytic properties of porous carbon sphere/InOOH nanocomposites

Visible-light-response porous carbon sphere/InOOH nanocomposites were synthesized through a facile hydrothermal process. The grain size of the crystalline InOOH is estimated around 14 nm, and the nanocomposites show a size range from 100 to 200 nm. The as-prepared nanocomposites possess a porous structure and a specific surface area of 45 m2 g−1. A possible in situ formation process was proposed after conducting a series of contrast experiments. Carbon spheres (CSs) were suggested to act as spherical templates and reducing reagents during the synthesis process of nanocomposites. The whole process involves the hydrolysis of indium ions, the redox reactions on surfaces groups of the CSs, and the dehydration of indium hydroxide. UV–Vis diffuse reflectance spectrum revealed a red shift of light absorption of the nanocomposites to about 600 nm compared with pure InOOH. The photocatalytic degradation for methylene blue was performed under visible light irradiation, 90 % of methylene blue was degraded after reacting for 6 h. We propose that the red shift was attributed to the interaction between carbon sphere and InOOH, and the CSs may act as photosensitizers.