Design and fabrication of WSe2/CNTs hybrid network: A highly efficient and stable electrodes for dye sensitized solar cells (DSSCs)

Abstract

This study presents a rational-designed structure and facile strategy to fabricate tungsten selenide/carbon nanotube (WSe2/CNT) hybrid photoanodes as promising anodes for DSSC applications. The fundamental physic-chemical properties proved that the uniform, pure and tubular WSe2/CNT hybrid nanoparticles were produced and WSe2 nanoparticles were anchored the CNT surface successfully. The WSe2/CNT hybrid nanostructure exhibits higher surface area (107.8 m2/g) and pore size (45.3 nm) than compared with pure WSe2 (86.2 m2/g and 19.8 nm). WSe2/CNT composite exhibits enhanced photo-conversion efficiency (8.85%), electro-catalytic activity and high electron life time (87 ns). The improved PCE of the WSe2/CNT composite is due to the CNTs can reduce electron-hole pair recombination and efficiently inhibit the aggregation of WSe2 for fully exposing the active edges. Those outstanding electrochemical performances of WSe2/CNT hybrid can be assigned to its unique nanoarchitecture: the CNT with high conductivity work as the skeleton of WSe2/CNT anode facilitating the electron transfer; the CNT can effectively prevent WSe2 from the aggregation and promote the in-situ growth of WSe2 on CNT. Moreover, the hybrid structure, which can allow for efficient ionic diffusion and easy electrolyte infiltration.