Mesoporous LDH Metastructure from Multiscale Assembly of Defective Nanodomains by Laser Shock for Oxygen Evolution Reaction

• Published in: Small (Weinheim an der Bergstrasse, Germany) Vol. 18; no. 35; pp. e2202403 - n/a
• Main Authors: Yi, Wendi, Jiang, Haoqing, Cheng, Gary J.
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01.09.2022
• Subjects: Assembly; Catalysts; Coral reefs; Defects; Dopants; Hydroxides; Lasers; layered double hydroxide (LDH); Molecular structure; multiscale; Nanomaterials; Nanostructure; Nanotechnology; oxygen evolution reaction (OER); Oxygen evolution reactions; porous
• ISSN: 1613-6810; 1613-6829
• DOI: 10.1002/smll.202202403

Laser is a powerful tool for the synthesis of nanomaterials. The intensive laser pulses delivered to materials within nanoseconds allow the formation of novel structures that are inaccessible for conventional methods. Layered double hydroxide (LDH) nanostructures with high porosity, suitable dopants, and rich defects are desirable for catalysts, however, tremendously difficult in a one‐pot synthesis. Here it is found that confined laser shock in solvent leads to the formation of nanoreactors which guide the assembly of multiscale LDH building units, larger nanosheets as frame and smaller nanodomains as building blocks. These nanodomains have rich vacancy defects and are interlocked in a high packed density of 1013 cm−2, leaving rich mesopores across the nanosheets and coral‐like morphology. Like the natural coral reef that has multiscale structure to accommodate different marine organisms, the coral‐like LDH metastructure provides large surface area and rich active sites for the interaction with guest molecules. Benefiting from the multiscale porous structure and rational dopant, this LDH catalyst exhibits a low overpotential of 220 mV at 10 mA cm−2 for oxygen evolution reaction (OER), standing as one of the best LDH catalysts to date. Porous layered double hydroxides (LDHs) with designated dopant and multiscale structures are synthesized by direct laser scribing in liquid. The laser‐induced LDHs with tunable composition and porous nature exhibit low overpotential of 220 mV at 10 mA cm−2 in oxygen evolution reaction (OER), benefiting from the favored chemical environment and fast mass transfer kinetics.