Influence of accelerating gas flow rate on the particle cohesion in room temperature cold sprayed scattering layer for plastic-based dye-sensitized solar cells

Mesoporous TiO2 coating was prepared by room temperature cold spraying with submicro-sized anatase TiO2 powder for scattering layer in plastic-based DSCs. The effect of accelerating gas flow rate on the microstructure, cohesion and optical property of the as-prepared TiO2 scattering layers was investigated. Results showed that the cohesion of the TiO2 scattering layer increased with the increase of accelerating gas flow rate due to the improved particle–particle connection by the particle impact at an increased velocity. The light-reflecting ability of the TiO2 scattering layers increased with the increase of coating thickness from 2 to 10 μm and decreased with the increase of accelerating gas flow rate from 3.5 to 7.5 L/min. By adding the scattering layer to the photoanode of the plastic-based DSCs, the conversion efficiency of the plastic-based DSCs was increased by a factor of 21% to 4.70%.