Bifacial Perovskite Solar Cells with Gold Transparent Electrodes Grown on Molybdenum Disulfide Surfaces

With the assist of van der Waals epitaxy on 2D material surfaces, conductive thin gold films down to several nanometers in thicknesses can be prepared on transferred monolayer MoS2 surfaces. Compared with the open circuit observed for the 6 nm Au film deposited on the blank glass substrate, a low sheet resistance of 20.35 Ω/sq is observed for the Au film deposited on the MoS2 surface. By using the MoS2-mediated thin Au films with different thicknesses of 6, 8, and 10 nm, compatible device performances with a reference device with thick 100 nm silver electrodes are observed for the device with 8 nm Au/monolayer MoS2 electrodes. A high bifaciality factor of 93.2% is also observed for the device. The results have demonstrated the potential of the nanometer-thick metal film-deposited 2D material surfaces for transparent electrode applications. The thin 2D material layers will not hinder the carrier transport between the contact electrode and the active region of optical devices.