Efficient and semi-transparent perovskite solar cells using a room-temperature processed MoOx/ITO/Ag/ITO electrode

In order to achieve semi-transparency in perovskite solar cells, the electrode materials must be as transparent as possible. In this work, MoOx/ITO/Ag/ITO (MoOx/IAI) thin films with high average transmittance of 79.90% between 400 nm and 900 nm were introduced as the top transparent electrode to explore its influences on optoelectronic properties of the fabricated perovskite solar cells. MoOx has been demonstrated previously as protection from sputtering damage using a conventional ITO top electrode, however it is shown here to provide protection from a sputtered IAI film that provides superior transparency and conductivity and is deposited using more favourable low temperature processing conditions. MoOx and Ag were thermally evaporated and ITO was radio-frequency magnetron sputtered at room temperature. The resulting semi-transparent solar cells showed power conversion efficiency of 12.85% (steady-state efficiency of 11.3%) along with a much-reduced degradation rate as compared to the reference device with only a Ag top electrode. With such a combination of performance and transparency, this work shows great promise in application of perovskite solar cells into window glazing products for building integrated photovoltaic applications (BIPV), powering internet of things (IoT) and combining into tandem solar cells with industrially mature photovoltaic technologies such as silicon and copper indium gallium di-selenide (CIGS).