Cobalt-boron-fluoride decorated graphitic carbon nitride composite as a promising candidate catalyst for highly efficient hydrogen production via NaBH₄ hydrolysis process

Herein, we have designed a cost-effective cobalt-boron-fluoride decorated graphitic carbon nitride (g-C₃N₄@Co–B–F) catalyst with a facile reduction method, which exhibits high catalytic activity and reusability in hydrogen (H₂) production via sodium borohydride (NaBH₄) hydrolysis process. The textural, structural and morphological characteristics of the fabricated catalysts were confirmed by XRD, FTIR, BET, SEM, EDX, TEM, and XPS characterization methods. Among the catalysts studied, the most efficient g-C₃N₄@Co–B–F catalyst exhibited remarkable catalytic activity with H₂ production rate (H₂PR) of 12813 mL_H2 min⁻¹ g_cat⁻¹ and turnover frequency (TOF) of 1439 h⁻¹ at 30 °C. The kinetics of H₂ production via NaBH₄ hydrolysis was elucidated employing the nth-order and Langmuir-Hinshelwood models. The activation energy (Ea) values calculated by fitting the nth-order and Langmuir-Hinshelwood kinetic models were found to be 26.32 kJ mol⁻¹ and 27.29 kJ mol⁻¹, respectively. The g-C₃N₄@Co–B–F catalyst continued to exhibit catalytic activity after five consecutive cycles, the H₂PR value decreased from 12813 to 4394 mL_H2 min⁻¹ g_cat⁻¹ and the TOF value decreased from 1439 to 482 h⁻¹, indicating structural and regenerative ability. Characterization analyses including SEM images, TEM images, EDX analysis and FTIR spectra of the g-C₃N₄@Co–B–F catalyst after five reuse cycles provided significant findings for the decrease in H₂PR and TOF values. Th results position the g-C₃N4@Co–B–F catalyst as a promising candidate for the further development of H₂ production technologies. The study also highlights the potential of the g-C₃N₄@Co–B–F catalyst for H₂ production, demonstrating its ability to provide sustainable solutions for various industrial and energy applications.