Inverted organic solar cells with TiOx cathode and graphene oxide anode buffer layers

Titanium oxide (TiOx) was introduced as an electron selective layer between the active layer and bottom electrode in inverted organic solar cells with graphene oxide (GO) an anode interfacial layer. The device with TiOx exhibited a significant enhancement in power conversion efficiency compared to that without TiOx, which indicates that TiOx efficiently blocked holes at the active/bottom layer. This device exhibits good stability over 2160 h of storage with only 3.67% reduction in efficiency. The dependence of the device performances on TiOx film thickness was also investigated.

Graphical abstractLong lifetime stability of inverted solar cells without PEDOT:PSS.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Anode and cathode buffer layers have been introduced to enhance device stability. ► The fabricated device shows excellent stability over 2160 h. ► The efficiency only degrades by 3.67% after 2160 h. ► Long lifetime stability is due to the absence of PEDOT:PSS.