18.73% efficient and stable inverted organic photovoltaics featuring a hybrid hole-extraction layer.

Developing efficient and stable organic photovoltaics (OPVs) is crucial for the technology's commercial success. However, combining these key attributes remains challenging. Herein, we incorporate the small molecule 2-((3,6-dibromo-9-carbazol-9-yl)ethyl)phosphonic acid (Br-2PACz) between the bulk-heterojunction (BHJ) and a 7 nm-thin layer of MoO in inverted OPVs, and study its effects on the cell performance.

Stacks of graphene with silicane or germanane: a first-principles study.

We report the results of density-functional theory calculations on the stability and properties of hybrid layered systems composed of graphene and silicane or germanane monolayers. We find that the interlayer binding energy between the sheets is comparable to that of graphite, indicating that the creation of the corresponding stacks is feasible. Moreover, we show that the hybrid systems are stable against the formation of defects caused by the transfer of hydrogen atoms from one layer to another.