Shining Light on Sulfide Perovskites: LaYS₃ Material Properties and Solar Cells

Abstract

The sulde perovskite LaYS 3 has been recently identied as a promising wide band gap photoabsorber material by computational screening techniques. In this study, we combine experiment and theory to comprehensively characterize LaYS 3 thin lms produced by sulfurization of sputter-deposited precursors. An attractive feature of LaYS 3 is its optimal band gap (2.0 eV) for application as a wide-band gap photoabsorber in 1 tandem solar energy conversion devices. Promisingly, the LaYS 3 lms are photoconductive, with a grain size in excess of 1 µm and comparable recombination timescales to state-of-the-art hybrid halide perovskite absorbers. Although the fabrication of solar cells based on LaYS 3 absorbers is complicated by the high temperature necessary to grow the compound, complete solar cells could be produced in this work by growing LaYS 3 on refractory metal back contacts. These are the rst reported solar cells based on a sulde perovskite absorber. A major reason for their poor performance could be the highly localized trap states observed directly by photoluminescence imaging of LaYS 3 , which may also explain the surprisingly long carrier lifetimes and the low carrier mobility found in this material.

Chalcogenide Materials and Derivatives for Photovoltaic Applications

“…The PL peak measured on the same sample was centered at 1.9 eV, so about100 meV lower than the bandgap extracted from ellispometry, likely due to trap or tail states (Figure ). In 2019, a full solar cell device was fabricated based on LaYS 3 absorbers using high‐temperature growth techniques, marking the first reported solar cells based on a sulfide perovskite absorber. It also indicates that the path to the successful fabrication of the solar cell using sulfide perovskites requires further optimization of the solar cell components specially chosen to tolerate the high‐temperature growth conditions.…”

A piperidinium salt stabilizes efficient metal-halide perovskite solar cells

“…The experimental setup for the time-resolved microwave conductivity (TRMC) measurement can be found in our previous work (49). A microwave-frequency oscillatory electric signal is generated using a Sivers IMA VO4280X/00 voltage-controlled oscillator (VCO).…”

“…An external trigger link is employed to trigger the oscilloscope before the laser fires. The photoconductance was evaluated from changes in the detector voltage using standard analysis as described in our previous works (49)(50)(51). All the measurements were conducted in air, without encapsulation, in the over-coupled regime.…”

Thermal stability of mobility in methylammonium lead iodide

“…An external trigger link is employed to trigger the oscilloscope before the laser fires. The photoconductance was evaluated from changes in the detector voltage using standard analysis [38][39][40]. All measurements were conducted in air, without encapsulation, in the under-coupled regime 2.3.…”

“…Acronyms are as follows: PC: Personal Computer, ITO: Indium Tin Oxide, VCO: Voltage Controlled Oscillator. Adapted with permission from[40]. Copyright (2019) American Chemical Society.…”