Laser-Induced Vertical Graphene Nanosheets for Electrocatalytic Hydrogen Evolution

Stefanos Chaitoglou; Yang Ma; Rogelio Ospina; Ghulam Farid; Jarosław Serafin; Roger Amade Rovira; Enric Bertran-Serra

doi:10.1021/acsanm.4c03320

Laser-Induced Vertical Graphene Nanosheets for Electrocatalytic Hydrogen Evolution

ACS Appl Nano Mater. 2024 Sep 25;7(19):22631-22639. doi: 10.1021/acsanm.4c03320. eCollection 2024 Oct 11.

Authors

Stefanos Chaitoglou^{1

2}, Yang Ma^{1

2}, Rogelio Ospina^{1

2

3}, Ghulam Farid^{1

2}, Jarosław Serafin^{1

2

4}, Roger Amade Rovira^{1

2}, Enric Bertran-Serra^{1

2}

Affiliations

¹ Department of Applied Physics, University of Barcelona, C/Martí i Franquès, 1, 08028 Barcelona, Catalunya, Spain.
² ENPHOCAMAT Group, Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona, C/Martí i Franquès, 1, 08028 Barcelona, Catalunya, Spain.
³ Centro de Investigación Científica y Tecnológica en Materiales y Nanociencias (CMN), Universidad Industrial de Santander, Piedecuesta, Santander P.C. 681011, Colombia.
⁴ Department of Inorganic and Organic Chemistry, University of Barcelona, C/Martí I Franquès, 1, 08028 Barcelona, Spain.

Abstract

Efficient and affordable electrocatalysts are fundamental for the sustainable production of hydrogen from water electrolysis. Here, an approach for the rapid production of laser-induced vertical graphene nanosheets (LIVGNs) through the exfoliation of the graphite foil under laser irradiation is presented. The density of the formed LIVGNs is ∼3 per 100 μm². On leveraging the inherent flexibility and conductivity of the graphite foil substrate, the resulting LIVGNs exhibit a 2.2-fold increase in capacitance, making them promising candidates for electrode applications. The laser-induced surface reconstruction introduces abundant sharp edges to the LIVGNs, enhancing their electrocatalytic potential for hydrogen evolution. In electrocatalytic hydrogen evolution tests in acidic media, the LIVGNs demonstrate superior performance with a remarkable decrease in the required overpotential at 10 mA cm^-2, from -555 mV for the pristine graphite foil to -348 mV for LIVGNs. This improvement is attributed to the active sites provided by the sharp edges, facilitating hydrogen species adsorption. Furthermore, the hydrophilic behavior of LIVGNs is enhanced through the anchoring of oxygen-containing groups, promoting the rapid release of the produced hydrogen bubbles. Importantly, the modified LIVGN electrode exhibits long-term stability across a wide range of current densities during chronoamperometry tests. This research introduces a transformative strategy for the efficient preparation of vertical graphene sheets on conductive graphite foils, showcasing their potential applications in electrocatalysis and energy storage.