Nanotechnology

Residual stress

Thermal stability

Creep

Engineering

Perovskite (structure)

Crystallite

Philosophy

Composite material

Stress relaxation

Thin film

Metallurgy

Materials science

Stress (linguistics)

Linguistics

Chemical engineering

Elastic modulus

Optoelectronics

Advanced Materials

To improve the photovoltaic performance (both efficiency and stability) in hybrid organic-inorganic halide perovskite solar cells, perovskite lattice distortion is investigated with regards to residual stress (and strain) in the polycrystalline thin films. It is revealed that residual stress is concentrated at the surface of the as-prepared film, and an efficient method is further developed to release this interfacial stress by A site cation alloying. This results in lattice reconstruction at the surface of polycrystalline thin films, which in turn results in low elastic modulus. Thus, a "bone-joint" configuration is constructed within the interface between the absorber and the carrier transport layer, which improves device performance substantially. The resultant photovoltaic devices exhibit an efficiency of 21.48% with good humidity stability and improved resistance against thermal cycling.

Interfacial Residual Stress Relaxation in Perovskite Solar Cells with Improved Stability