Effect of gold nanoparticles on transmittance and conductance of graphene oxide thin films and efficiency of perovskite solar cells

The structural and optoelectronic properties of graphene oxide (GO) bulk material were studied, and conductance and transmittance of GO thin films in absence and presence of AuNPs were optimized for further applications. GO with 0.25 mg/mL and AuNPs (0.5 mL) on GO thin films (0.25 mg/mL) were observed to have highest transmittance of 75% and 72%, respectively, and highest conductance of 7.9x10(3) S and 8.2x10(3) S, respectively. Further, these thin films were utilized as a hole transport layer (HTL) for a prototype inverted perovskite solar cell structure. GO and AuNPs/GO deposited on FTO glass show efficiency of 1.35% and 1.25%, respectively. This decrease in efficiency is associated with the deteriorated crystalline structure of perovskite in the presence of AuNPs and similar HOMO level of AuNPs as of GO, which competes hole transfer.