The Polymer Society of Korea

Abstract

We suggest a new and feasible approach for the photoelectrochemical (PEC) application of distributed Bragg reflector (DBR) films using lamella-forming PS-b-P2VP self-assembly. A weak hydroxy acid of lactic acid (LA) in a methanol solution was incorporated into the 2VP units to favourably swell and protonate the P2VP domains of the defect-free films, leading to the selective expansion of LA-incorporated P2VP domains. The reflected wavelengths of the BCP-based DBR films were cooperatively tuned by controlling the crosslinking density in the P2VP domains immediately before the LA incorporation. The reflected wavelength (λ_m) was effectively tuned by varying the weight fraction of 1,4-dibromobutane (W_DBB). These narrow-width, high-reflectance DBR films were integrated into the rear of photoanodes to scrutinize the optimal λ_m for the best PEC performance, where the photon-recycling process also allowed the reflected lights to illuminate the backside.