The presence of non-perovskite δ-phase at the buried interface between the perovskite active layer and the charge transport layer significantly hinders the commercialization of perovskite solar cells. This is primarily due to the difficulty in detecting it during the initial device fabrication. This unwanted phase acts as a nucleation site for degradation and is notoriously difficult to eliminate once formed.… Read More

The random distribution of shunt resistance in organic photovoltaics (OPVs) compromises device performance and reproducibility, particularly under low-light conditions, which are typical operation conditions of Ambient Internet of Things (A-IoT) applications. In this work, we identify the morphological origin of shunt resistance and introduce a universally applicable strategy to mitigate it in both OPV devices and mini-modules.… Read More

The complex structure within the photoactive layer of organic photovoltaics (OPVs) makes it challenging to establish a clear structure-performance relationship. In this study, we investigate the morphological origins of performance limitations in OPVs, with a particular focus on deep-trap-assisted monomolecular recombination. Through advanced morphological and device-physics characterization techniques, we identify isolated crystalline and amorphous acceptor domains as primary sources of deep electron traps, due to the substantial LUMO offset between donor and acceptor materials employed in high-performance OPVs.… Read More