Visible-Light Excitable CuO/Na-P- g -C 3 N 4 Heterojunction Catalysts for Naphthalene Photodegradation

Copper oxide deposited sodium and phosphorus co-modified g -C 3 N 4 composite catalysts (CuO/Na-P- g -C 3 N 4 ) were successfully designed and prepared by a facile thermal polycondensation and chemical deposition. The structural and photoelectrochemical properties of the prepared photocatalysts were studied by XRD, FT-IR, BET, SEM, TEM, EDX, XPS, UV-vis DRS, PL, and EIS techniques, and the photocatalytic performance in the naphthalene photodegradation under visible light irradiation was evaluated. The results showed that the successful construction of heterojunction structure would be formed between CuO and Na-P- g -C 3 N 4 interfaces, and the most weak PL intensity for the (6%)CuO/Na-P- g -C 3 N 4 sample with the lowest bandgap energy of 1.90 eV would be obtained. The (6%)CuO/Na-P- g -C 3 N 4 sample exhibited highest naphthalene degradation among all the g -C 3 N 4 -based catalyst of 87.1% in 180 min owing to the promotion for the migration and separation of photoexcited electron and hole pairs. The photocatalytic degradation rate for the (6%)CuO/Na-P- g -C 3 N 4 sample would not be significantly dropped after repeated use for 5 times. The excellent catalytic performance with good stability and durability suggested that it would be a potential candidate for the naphthalene photodegradation to protect the environment.