石墨型C<sub>3</sub>N<sub>4</sub>在泡沫陶瓷表面的原位负载及可见光催化空气净化应用
摘要
g-C<sub>3</sub>N<sub>4</sub> is a metal-free visible light photocatalyst with wide promising application. In this work, an <italic>in situ</italic> approach of dissolution- recrystallization-thermal-treatment is developed for effective immobilization of g-C<sub>3</sub>N<sub>4</sub> on the support using dicyandiamide as precursor. The immobilized g-C<sub>3</sub>N<sub>4</sub> on Al<sub>2</sub>O<sub>3</sub> ceramic foam was firm enough owing to the special physicochemical interaction between g-C<sub>3</sub>N<sub>4</sub> and Al<sub>2</sub>O<sub>3</sub>. The g-C<sub>3</sub>N<sub>4</sub> samples were analyzed by techniques. With a systematic investigation on the effects of different pyrolysis time on the microstructure and photocatalytic activity of g-C<sub>3</sub>N<sub>4</sub>, it was found that the immobilized g-C<sub>3</sub>N<sub>4</sub> with a pyrolysis time of 4 h exhibited optimal NO removal ratio of 57.9%. The outstanding activity can be ascribed to the increased surface area and porosity and promoted charge separation. This work could provide an in situ immobilization approach based on the interaction between the photocatalyst and support, as well as the technical support and theoretical basis in practical application of g-C<sub>3</sub>N<sub>4</sub> in air purification.