Mechanical Properties of APbX3 (A=Cs or CH3NH3; X=I or Br) Perovskite Single Crystals

TL;DR

This study measures the elastic and hardness properties of APbX3 perovskite single crystals, linking their mechanical characteristics to optoelectronic performance and potential applications.

Contribution

It provides experimental nano-indentation data on elastic modulus and hardness for specific perovskite crystals, supporting theoretical values and classifying these materials based on their mechanical properties.

Findings

Young's moduli: 14, 19.5, and 16 GPa for different compositions.

Experimental results align with theoretical calculations.

Insights into self-healing, ion diffusion, and manufacturing relevance.

Abstract

The remarkable optoelectronic, and especially photovoltaic performance of hybrid-organic-inorganic perovskite (HOIP) materials drives efforts to connect materials properties to this performance. From nano-indentation experiments on solution-grown single crystals we obtain elastic modulus and nano-hardness values of APbX3 (A = Cs, CH3NH3 and X = I, Br). The Youngs moduli are about 14, 19.5 and 16 GPa, for CH3NH3PbI3, CH3NH3PbBr3 and CsPbBr3, respectively, lending credence to theoretically calculated values. We discuss possible relevance of our results to suggested self-healing, ion diffusion and ease of manufacturing. Using our results, together with literature data on elastic moduli, we classified HOIPs amongst relevant materials groups, based on their elasto-mechanical properties.