Metal halide perovskites are heralded as pivotal materials for next-generation photovoltaic technologies, thanks to their outstanding optoelectronic properties and the ease with which they can be processed from solution. Nevertheless, residual tensile stress often builds up at the buried interface—the area where the perovskite film meets the electron transport layer. Prolonged exposure to ultraviolet light exacerbates this issue, as the interplay between stress and defects triggers lattice distortion, the emergence of impurity phases, and interface degradation. These phenomena collectively undermine the device's photoelectric conversion efficiency and operational longevity. Traditional interface modification materials, which offer only static defect passivation and structural protection, struggle to adapt to the ever-shifting light, thermal, and mechanical conditions encountered during device operation. Hence, the development of a functional layer capable of actively responding to the operational environment and dynamically adjusting interface stress is paramount for simultaneously boosting both the efficiency and stability of perovskite solar cells.