Researchers from Gdańsk University of Technology, National Taiwan University, Chang Gung University and Ming-Chi University of Technology have investigated the degradation mechanisms of semitransparent perovskite solar cells (PSCs) built in an inverted architecture, combining outdoor field testing with laboratory-accelerated aging and drift–diffusion modelling to learn which stressors actually drive performance loss.
Tracking the devices outdoors in Gdańsk under ISOS-O-3 conditions across two seasonal windows produced sharply different results. Averaged over four devices, the cells retained 84% of their initial PCE after 1150 hours in the summer season, but retained 77% after a much longer 3100 hours in the fall. The team set out to test whether these differing seasonal results stem from a shifting balance between light-driven and temperature-driven degradation, rather than a single dominant cause.
To separate those causes, the outdoor trends were compared against controlled accelerated tests. Damp-heat aging in the dark at 65°C and 65% relative humidity (ISOS-D-3) produced a two-stage behavior: an initial thermal activation phase that actually improved performance, followed by a regime in which defect-related recombination in the perovskite layer became an increasingly important loss channel. Continuous-illumination testing (ISOS-L-1 and ISOS-L-3) pointed to a different culprit - sustained light exposure primarily induced transport-related losses rather than recombination-driven ones.
To resolve the underlying charge dynamics, the group used modulated light intensity measurements together with drift–diffusion modelling, analyzing both bulk transport and recombination in the perovskite and the behavior at its interfaces with the charge-transport layers. In the ISOS-L-3 case, simulations grounded in light-intensity-dependent J(V) analysis showed that the observed losses are consistent with a reduction in the effective charge carrier mobility - a concrete signature of the transport degradation seen under continuous light.
Taken together, the work demonstrates a combined experimental and simulation-based methodology for identifying the dominant degradation pathways in semitransparent PSCs across both outdoor and laboratory-accelerated conditions, mapping seasonal outdoor performance onto the distinct fingerprints of thermal/humidity stress and continuous illumination.
