Room-temperature electrochemically deposited polycrystalline SnO2 with adjustable work function for high-efficiency perovskite solar cells

In the last two years, studies on SnO2 preparation and optimization have proved to be effective paths toward the Schottky limit of perovskite solar cells. Herein, we used an electrochemical deposition method to obtain polycrystalline SnO2 film at room temperature for the first time. The method has the advantage of simplicity and efficiency using electrochemistry to realize deposition, adsorption, and protection of the SnO2 film, avoiding a more complex regulation process than the chemical bath deposition method. Benefiting from the optimization process, the method could achieve adjustable work function of the SnO2 film by controlling the pH of the electrolyte, which is conducive for reducing mismatched energy levels between the SnO2 film and the perovskite layer. Besides, the obtained SnO2 film is densely and uniformly distributed along the substrate profile, leading to better light transmission. More importantly, this method can be applied to prepare SnO2 film on large area and flexible substrates. Finally, the device based on SnO2 film prepared with pH = 1 electrolyte achieves the highest performance of 22.85%, which is higher than that of the device based on the commercial colloidal dispersion SnO2 film (21.72%). These multi-advantages of the method make it competitive for future commercialization.

Automated summary

Recent studies have shown that SnO2 preparation and optimization can effectively improve the Schottky limit of perovskite solar cells. In this study, a polycrystalline SnO2 film was obtained for the first time using an electrochemical deposition method at room temperature. The method is simple and efficient, allowing for adjustable work function and better light transmission. It is also applicable for large area and flexible substrate preparation, making it competitive for future commercialization.