Bi2S3@Ag2S nano-heterojunction decorated self-floating carbon fiber cloth and enhanced solar-driven photothermal-photocatalytic performance.

The difficult recycle, secondary pollution and insufficient sunlight utilization of powder photocatalysts are main obstacles for practical applications. Bi2S3@Ag2S heterojunction supported on surface of carbon fiber cloth (CC) are fabricated through hydrothermal in-situ growth method combined with ultrasonic loading strategy, which can be self-floated on water surface. Bi2S3@Ag2S nano-heterojunction with narrow band gap shows enhanced full spectrum absorption, which is in favor of improving the photocatalytic-photothermal performance. Self-floating CC as a substrate not only absorbs solar light converting to thermal energy, but also favors the recycle of catalysts. The resultant Bi2S3@Ag2S/CC composite films exhibit excellent photothermal conversion performance and photocatalytic degradation activity for tetracycline hydrochloride in low temperature wastewater under simulated sunlight. Experimental results confirm that the superoxide group (·O2-) is the main factor for the robust catalytic performance. The good photothermal-photocatalytic performance can be ascribed to the efficient absorption of sunlight for self-floating characteristics and high charge carriers separation efficiency of Bi2S3@Ag2S nano-heterojunction. This novel self-floating photothermal-photocatalytic film will have potential applications in fields of environment.