Enhancing Carrier Transport Properties of Two-Dimensional Perovskite Cs₂PbI₂Cl₂ through Strain Engineering

Area of Science:

• Materials Science
• Condensed Matter Physics
• Solid-State Chemistry

Background:

• Two-dimensional (2D) lead-halide perovskites offer enhanced stability and in-plane carrier mobility for optoelectronic applications.
• Cesium lead iodide chloride (Cs2PbI2Cl2) is a promising 2D perovskite material.

Purpose of the Study:

• To investigate the effects of strain engineering on the quantum transport properties of Cs2PbI2Cl2.
• To optimize the performance of Cs2PbI2Cl2-based optoelectronic devices.

Main Methods:

• Density Functional Theory (DFT) was used to study electronic and excitonic properties.
• Non-equilibrium Green's Function (NEGF) method examined carrier transport characteristics.
• A two-probe device model compared pristine and strained Cs2PbI2Cl2 properties.

Main Results:

• Compressive strain reduced the band gap, carrier effective mass, and exciton binding energy.
• Strain enhanced electron transmission and device conductance, leading to higher current.
• Strain and polarization-dependent photocurrents were observed under linearly polarized light.

Conclusions:

• Strain engineering is an effective strategy to tune and enhance the in-plane carrier transport properties of 2D Cs2PbI2Cl2.
• Optimized strain can significantly improve the performance of Cs2PbI2Cl2-based optoelectronic devices.