Enhancing the Electrical Performance of Formamidinium Perovskites through WS₂ Nanotube Incorporation

Organometal lead-halide perovskite (LHPs) thin films are on the brink of commercialization as their performance reaches that of silicon solar cells. As organometal lead-halide perovskite films are solution-processed, they are particularly suitable for the preparation of composite films with other semiconductor materials, which can improve the electronic properties of the films. In this work, WS₂ hollow nanotubes, synthesized using a high-temperature vapor-gas-solid (VGS) reaction, are dispersed inside the perovskite thin film and investigated by utilizing the capabilities of solid-state impedance spectroscopy (IS) to measure electrical conductivity. By adding an energy-level-compatible semiconducting material inside the absorber thin film, we were able to observe an increase in the conductivity of the film without diminishing optical properties, showing that WS₂ nanotubes can be used as additives in the preparation of perovskite thin films.