A transparent photovoltaic device of Cu2O/SnO2 QDs/SnO2 pn junction with difunctional homogeneous SnO2 QDs transition layer

Carrier efficiency is the most crucial factor for the transparent photovoltaic devices. In this work, the Cu2O/SnO2 QDs/SnO2 pn junction transparent photovoltaic device is fabricated via a continuous sputtering-chemical-annealing method. As revealed, the as-prepared transparent photovoltaic device exhibits high transparency of ∼80% in visible light, noticeable photovoltaic conversion enhancement of ∼1.1 × 103 folds, and decent stability during the 20,000 s cycle. It could be mainly ascribed to that the SnO2 QDs with high quantum yield and appropriate potential can accelerate charge carrier injection and separation/migration for increasing carrier efficiency. Additionally, the SnO2 QDs with multiple reflections/interference can improve pn junction interface and increase solar efficiency while being transparent.