WXy/g-C3N4 (WXy=W2C, WS2, or W2N) Composites for Highly Efficient Photocatalytic Water Splitting

The development of earth-abundant, economical, and efficient photocatalysts to boost water splitting is a key challenge for the practical large-scale application of hydrogen energy. In this study, g-C3N4 loaded with different tungsten compounds (W2C, WS2, and W2N) is found to exhibit enhanced photocatalytic activities. W2C/g-C3N4 displays the highest activity for the photocatalytic reaction with a H-2 evolution rate of up to 98 mu mol h(-1), as well as remarkable recycling stability. The excellent photocatalytic activity of W2C/g-C4N3 is attributed to the suitable band alignment in W2C/g-C4N3 and high HER activity of the W2C cocatalyst, which promotes the separation and transfer of carriers and hydrogen evolution at the surface. These findings demonstrate that the tungsten carbide cocatalyst is more active for the photocatalytic reaction than the sulfide or nitride, paving a way for the design of novel and efficient carbides as cocatalysts for photocatalysis.