The Role of the Graphene Oxide (GO) and PEO Treated-Zinc Oxide (ZnO/PEO) Intermediate Electrode Buffer Layer in Vacuum-Free Quantum Dots Solar Cell

The vacuum-free quantum dots solar cell (VFQDSC) was fabricated without using any vacuum process. The spherical iron pyrite (FeS₂) nanoparticles (SNPs) and ZnO nanoparticles (NPs) were synthesized and characterized. In the device structure, FeS₂ SNPs were used as an acceptor material (n-type), and the low band gap polymer of poly[4,8-bis(2-ethylhexyloxyl)benzo[1,2-b:4,5-b′]-dithiophene-2,6-diyl-alt-ethylhexyl-3-fluorothieno[3,4-b]thiophene-2-carboxylate-4,6-diyl] (PBT7) was used as a donor material (p-type). In this study, we first applied the graphene oxide (GO) as the hole transport buffer layer (HTBL) and zinc oxide (ZnO) as an electron transport buffer layer (ETBL), which were considered to improve the charge transportation efficiency of the device’s system. The device with the structure of the Glass/ITO/HTBL/FeS₂ SNPs, PBT7/ ETBL/E-GaIn were fabricated with a maximum power conversion efficiency (PCE) of 3.6%.