Self-assembled nano-leaf/vein bionic structure of TiO2/MoS2 composites for photoelectric sensors

Abstract

Inspired by the leaf/vein structure of leaves which effectively supports the photosynthesis of green plants, a nano-leaf/vein bionic structure of self-assembled TiO₂/MoS₂ composites is applied to induce the reversible photochromic reactions of methylene blue (MB) for the first time. This reversible photochromic phenomenon gives a novel performance for the TiO₂/MoS₂ composites and expands their applications. Similar to the case where the natural vein network in leaves ensures the efficient material transfer and energy exchange for photosynthesis, the bionic internal MoS₂ vein network in the composites ensures the efficient separation and directional transfer of photo-generated carriers to restrain the photocatalytic degradation reactions and to enhance the reversible photochromic reactions. Furthermore, the photosensitive applications of the TiO₂/MoS₂/MB systems with such a self-assembled nano-leaf/vein bionic structure are discussed with two typical photoelectric sensory models for both controllers and detectors.