The proton conductivity in benzimidazolium azelate under moderate pressure

TL;DR

This study uses kinetic Monte Carlo simulations to analyze how moderate hydrostatic pressure affects proton conductivity in benzimidazolium azelate, revealing key parameters influencing transport and potential for material optimization.

Contribution

The paper introduces a modified model that accurately simulates pressure effects on proton conductivity, highlighting hydrogen bond length and lattice vibrations as primary factors.

Findings

Pressure increases proton conductivity via hydrogen bond length and lattice vibrations.

The model aligns well with experimental data under moderate pressure.

A predicted crossover in temperature dependence occurs at high pressure.

Abstract

The kinetic Monte Carlo method is applied to examine effects of hydrostatic pressure on the benzimidazolium azelate (BenAze) proton conductivity. Following the experimental indications the recently proposed model has been modified to simulate the transport phenomena under moderate pressure, resulting in a very good agreement between numerical and experimental results. We demonstrate that the pressure-induced changes in the proton conductivity can be attributed to solely two parameters: the length of the hydrogen bond and the amplitude of lattice vibrations while other processes play a more minor role. It may provide an insight into tailoring new materials with improved proton-conducting properties. Furthermore, in high-pressure regime we anticipate the crossover from the increasing to decreasing temperature dependence of the proton conductivity resulting from the changes in the hydrogen-bond activation barrier with increased pressure.