Enhanced electron-hole separation in CoWO4/C3N5 photocatalysts for degradation of diverse dyes and environmental remediation

The inefficient separation of photogenerated charge carriers significantly limits the photocatalytic efficiency of nitrogen-enriched graphitic carbon nitride (g-C 3 N 5 ). To address this issue, a CoWO 4 /C 3 N 5 type-II heterojunction was fabricated via a water-bath-assisted process followed by calcination, providing an alternative to conventional hydrothermal approaches. The optimal composite (2% CoWO 4 /C 3 N 5 ) demonstrated exceptional photocatalytic activity and broad-spectrum applicability, achieving degradation rates of 71.24% for MO, 82.26% for MB, and 80.09% for RhB within 20 min. It also maintained high efficiency in treating complex mixed-dye systems, underscoring its practical potential. Phytotoxicity tests using mung bean seeds and natural lotus leaves further indicated that the treated dye solution exhibited no obvious toxicity and even promoted root elongation. The improved performance can be attributed to the broadened visible-light response and the efficient charge separation/transfer enabled by the type-II heterojunction, which also contributes to the structural stability of the photocatalyst. Download: Download high-res image (272KB) Download: Download full-size image