Nanosecond Laser-Induced Conversion of Leaf-Like Co-MOF to Nanoscale Co@N-gCarbon for Enhanced Multifunctional Electrocatalytic Performance

Conversion of metal–organic frameworks (MOFs) into metal-nitrogen-doped carbon (M–N–C) catalysts requires a high-temperature process and longer processing time under a protective atmosphere. This study utilizes a low-energy nanosecond laser processing (LP) technique to convert aqueous synthesized 2D leaf-like Co-MOF (L-Co-MOF) into nanoscale cobalt metal encapsulated within a nitrogen-doped graphitic carbon matrix (Co@N-gC, Co-LP) in a shorter period under air atmosphere. The laser-induced process results in the formation of Co@N-gC with smaller Co particle size, uniform distribution, and better interaction with the carbon support compared to the conventional pyrolysis process (CP). LP catalysts result in enhanced multifunctional electrocatalytic activity over CP (Co-CP) catalysts owing to the tunable metal–support interaction, higher charge transfer, and presence of multiactive sites. Under optimized conditions (laser fluence: 5.76 mJ cm⁻² and scan speed: 10 mm s⁻¹), the Co-LP-5 catalyst exhibits better ORR performance, with onset and half-wave potentials of 0.92 and 0.76 V, respectively. Additionally, Co-LP-5 delivers excellent water-splitting performance, with OER and HER overpotentials of 380 and 280 mV, respectively, achieving an overall energy efficiency of 77.85%. Furthermore, Co-LP-5 demonstrates exceptional durability over 48 h of real-time testing, outperforming the Co-CP, and the proposed low-energy LP is viable for fabricating multifunctional catalysts.