Steric engineering of metal-halide perovskites with tunable optical band gaps

Abstract

Owing to their high energy-conversion efficiency and inexpensive fabrication routes, solar cells based on metal-organic halide perovskites have rapidly gained prominence as a disruptive technology. An attractive feature of perovskite absorbers is the possibility of tailoring their properties by changing the elemental composition through the chemical precursors. In this context, rational in silico design represents a powerful tool for mapping the vast materials landscape and accelerating discovery. Here we show that the optical band gap of metal-halide perovskites, a key design parameter for solar cells, strongly correlates with a simple structural feature, the largest metal-halide-metal bond angle. Using this descriptor we suggest continuous tunability of the optical gap from the mid-infrared to the visible. Precise band gap engineering is achieved by controlling the bond angles through the steric size of the molecular cation. Based on these design principles we predict novel low-gap perovskites for optimum photovoltaic efficiency, and we demonstrate the concept of band gap modulation by synthesising and characterising novel mixed-cation perovskites.

This manuscript was submitted for publication on March 6th, 2014. Many of the results presented in this manuscript were presented at the International Conference on Solution processed Semiconductor Solar Cells, held in Oxford, UK, on 10-12 September 2014. The manuscript is 37 pages long and contains 8 figures

References in corpus (1)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials

Cited by in corpus (19)

• Perovskite-perovskite tandem photovoltaics with optimized bandgaps
• Identifying defect-tolerant semiconductors with high minority carrier lifetimes: Beyond hybrid lead halide perovskites
• Many-body perturbation theory calculations using the yambo code
• Phonon anharmonicity, lifetimes and thermal transport in CH${}_3$NH${}_3$PbI${}_3$ from many-body perturbation theory
• GW quasiparticle band gap of the hybrid organic-inorganic perovskite CH${}_3$NH${}_3$PbI${}_3$: Effect of spin-orbit interaction, semicore electrons, and self-consistency
• Temperature Dependence of the Energy Levels of Methylammonium Lead Iodide Perovskite from First Principles
• Atomic-scale imaging of CH3NH3PbI3 structure and its decomposition pathway
• Chemically-Localized Resonant Excitons in Silver-Pnictogen Halide Double Perovskites
• Lattice dynamics and ferroelectric properties of the nitride perovskite ${\mathrm{LaWN}}_3$
• Room temperature dynamic correlation between methylammonium molecules in lead-iodine based perovskites: An ab-initio molecular dynamics perspective
• A New Perspective on the Role of A-site Cation in Perovskite Solar Cells
• Topological defects at octahedral tilting plethora in bi-layered perovskites
• Tuning the optical bandgap in hybrid layered perovskites through variation of alkyl chain length
• Mixed Formamidinium-Methylammonium Lead Iodide perovskite from first-principles: Hydrogen-bonding impact on the electronic properties
• Mixed-anion mixed-cation perovskite (FAPbI${}_3$)${}_{0.875}$(MAPbBr${}_3$)${}_{0.125}$: an ab-initio molecular dynamics study
• Influence of Crystal Structure and Composition on Optical and Electronic Properties of Pyridinium-based Bismuth Iodide Complexes
• Ultrafast Chirality-dependent Dynamics from Helicity-resolved Transient Absorption Spectroscopy
• Role of the Adsorption of Alkali Cations on Ultrathin $n$-Layers of Two-dimensional Perovskites
• Role of Inorganic Cations in the Excitonic Properties of Lead Halide Perovskites