Self-Powered Ultra-Broadband and Flexible Photodetectors Based on the Bismuth Films by Vapor Deposition

Bismuth (Bi), as a topological semimetallic material, has received widespread attention on account of its fascinating properties. Here, Bi films were successfully grown through a direct and facile vapor deposition method on 300 nm SiO2/Si (SiO2) and polyimide (PI) substrates. The Bi films were utilized further to fabricate rigid and flexible photodetectors. The rigid photodetector based on Bi/SiO2 shows fast, highly stable, self-powered, and ultra-broadband photoresponses. The flexible Bi/PI photodetector exhibits durability and reproducibility in photoresponse behaviors under bending with various curvature radii and after hundreds of bending cycles. Our results demonstrated that the Bi films by vapor deposition have great application potentials in the next generation of optoelectronic devices.