Graphitic Carbon Nitride Platforms Modified with Gold-Aryl Nanoparticles for Efficient Electrocatalytic Hydrogen Evolution

ABSTRACT

Electrocatalytic hydrogen evolution reactions (HER) offer an enduring strategy for hydrogen fuel production and are vital for sustainable energy conversion and storage. To explore efficient and durable HER electrocatalysts, we fabricated gold-aryl nanoparticles (AuNPs-COOH) anchored on graphitic carbon nitride (g-C₃N₄) sheets by reducing aryldiazonium tetrachloroaurate(III) salt with sodium borohydride at room temperature in water. Two different nanocomposites, AuNPs-COOH-g-C₃N₄ (H) (higher amount of g-C₃N₄) and AuNPs-COOH-g-C₃N₄ (L) (lower amount of g-C₃N₄) were prepared. Contact angle measurements revealed that the increased surface wettability of the nanocomposites on glass and silicon wafer surfaces compared to pristine g-C₃N₄. Cyclic voltammetry, electrochemical impedance spectroscopy, double-layer capacitance, linear sweep voltammetry, and chronoamperometry measurements revealed that AuNPs-COOH-g-C₃N₄ (L) displayed the best HER performance in 0.1 M H₂SO₄ electrolyte. Overall, nanocomposites exhibited higher electrocatalytic activity compared to bare AuNPs-COOH and pristine g-C₃N₄ in current density and onset potential values. The AuNPs-COOH-g-C₃N₄ (L) nanocomposite offered an excellent electrocatalytic activity and displayed a current density of 53.4 mA/cm² at 0.72 V vs RHE, which is nearly twice compared to bare AuNPs-COOH of 33.1 mA/cm². In addition, the nanocomposite showed the lowest onset potential of 0.14 V vs RHE compared to 0.26 V and 0.31 V for AuNPs-COOH-g-C₃N₄ (H) and AuNPs-COOH, respectively.

KEYWORDS:

• Graphitic carbon nitride
• gold-aryl nanoparticles
• electrocatalysis
• wettability
• hydrogen evolution reaction

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/02603594.2022.2078316.

Additional information

Funding

CH acknowledges the support of the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) [No. 2021R1A2C1093183, No.2021R1A4A1032746]; AAM acknowledges the University of Sharjah support of competitive grants [150-2142-017-P, 160-2142-029-P].