In situ growth of columnar MoO3 buffer layer for organic photovoltaic applications

•We have developed an in situ method to prepare MoO3 thin film.•The composition and microstructure of the thin film were studied.•The MoO3 film possessed columnar morphology.•The MoO3 film was proved to have superior property in organic photovoltaics.

Columnar MoO3 in situ growth prepared from direct converting soluble Mo-containing precursor during active layer thermal annealing was utilized as anode buffer layer to fabricate organic bulk heterojunction photovoltaics. The columnar morphology could improve the interface contact between active layer and buffer layer. The structure and phase of in situ formed MoO3 were studied by X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). We demonstrated that the organic photovoltaic devices based on P3HT:PC61BM using in situ formed columnar MoO3 as anode buffer layer presented a high open-circuit voltage and fill factor leading to an efficiency of 3.92%, which is higher than the controlled PEDOT:PSS-based devices.

Graphical abstractColumnar MoO3 in situ growth prepared from direct converting soluble Mo-containing precursor during active layer annealing in organic photovoltaic device fabrication was utilized as anode buffer layer which simultaneously increase short circuit current and fill factor, resulting in enhanced device efficiency.Figure optionsDownload full-size imageDownload as PowerPoint slide