# Semimetallicity and Negative Differential Resistance from Hybrid Halide Perovskite Nanowires

## TL;DR

This paper investigates the electronic properties of hybrid halide perovskite nanowires, revealing their semimetallic nature and potential for negative differential resistance, which could enable advanced electronic device applications.

## Contribution

It introduces the first-principles study of 1D hybrid perovskite nanowires, demonstrating their stability, semimetallicity, and NDR behavior, highlighting new electronic functionalities.

## Key findings

- PbI$_3$ frameworks are stable and semimetallic.
- Nanowire junctions exhibit high current densities.
- Negative differential resistance arises from quantum hybridization.

## Abstract

In the rapidly progressing field of organometal halide perovskites, the dimensional reduction could open up new opportunities for device applications. Herein, taking the recently synthesized trimethylsulfonium lead triiodide (CH$_3$)$_3$SPbI$_3$ perovskite as a representative example, we carry out first-principles calculations and study the nanostructuring and device application of halide perovskite nanowires. We find that the one-dimensional (1D) (CH$_3$)$_3$SPbI$_3$ structure is structurally stable, and the electronic structures of higher-dimensional forms are robustly determined at the 1D level. Remarkably, due to the face-sharing [PbI$_6$] octahedral atomic structure, the organic ligand-removed 1D PbI$_3$ frameworks are also found to be stable. Moreover, the PbI$_3$ columns avoid the Peierls distortion and assume a semimetallic character, contradicting the conventional assumption of semiconducting metal-halogen inorganic frameworks. Adopting the bundled nanowire junctions consisting of (CH$_3$)$_3$SPbI$_3$ channels with sub-5 nm dimensions sandwiched between PbI$_3$ electrodes, we finally obtain high current densities and large room-temperature negative differential resistance (NDR). It will be emphasized that the NDR originates from the combination of the near-Ohmic character of (CH$_3$)$_3$SPbI$_3$-PbI$_3$ contacts and a novel NDR mechanism that involves the quantum-mechanical hybridization between channel and electrode states. Our work demonstrates the great potential of low-dimensional hybrid perovskites toward advanced electronic devices beyond actively-pursued photonic applications.

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Source: https://tomesphere.com/paper/1812.00729