Dislocation-enhanced piezoelectric catalysis of KNbO3 crystal for water splitting

TL;DR

This study demonstrates that mechanically introduced high-density dislocations in KNbO3 crystals significantly enhance their piezocatalytic efficiency for water splitting, offering a sustainable alternative to traditional methods.

Contribution

It introduces a room-temperature cyclic scratching technique to engineer dislocations in KNbO3, improving piezocatalytic performance for hydrogen production.

Findings

Dislocations induce local strain and modify electronic environment.

Enhanced surface reactivity and charge separation observed.

Improved hydrogen production efficiency in dislocation-engineered crystals.

Abstract

Dislocations in oxides with ionic/covalent bonding hold the potential of harnessing versatile functionalities. Here, high-density dislocations in a large plastic zone in potassium niobate (KNbO3) crystals are mechanically introduced by room-temperature cyclic scratching to enhance piezocatalytic hydrogen production. Unlike conventional energy-intensive, time-consuming deformation at high temperature, this approach merits efficient dislocation engineering. These dislocations induce local strain and modify the electronic environment, thereby improving surface reactivity and charge separation, which are critical for piezocatalysis. This proof-of-concept offers a practical and sustainable alternative for functionalizing piezoelectric ceramics. Our findings demonstrate that surface-engineered dislocations can effectively improve the piezocatalysis, paving the way for efficient and scalable piezocatalytic applications.