Fabrication of Co- and P-Doped Laser-Induced Graphene for Use in Water Splitting Applications
Anh Phan Nguyen, Huan Minh, Rizwan Khan, Changyoung Ryu, Chau Van Tran, Seok‐min Kim, Jung Bin In
Abstract
The efficient production of high-purity hydrogen for green energy using water splitting requires cost-effective and high-performance electrodes for the hydrogen evolution reaction (HER). Conventional catalyst coating methods, such as chemical vapor deposition and electrochemical deposition, are often complex and expensive; thus, there is a need to develop more efficient alternatives. In this respect, cost-effective nickel-foam-based catalytic electrodes have demonstrated promising HER activity, while laser-induced graphene (LIG) offers desirable characteristics such as high microporosity, excellent conductivity, chemical stability, a 3D structure, and scalability. This study focuses on utilizing LIG as a catalyst support for the deposition of catalytic materials on nickel foam for the HER. Our proposed fabrication technique involves drop-coating cobalt and phosphorus in a poly(amic acid) solution onto nickel foam, followed by annealing to form a doped polyimide polymer. Subsequent CO 2 laser irradiation converts the polymer into conductive LIG doped with cobalt oxide and phosphorus (CoP-LIG). The CoP-LIG on nickel foam (CoP-LIG-Ni) exhibits significantly enhanced HER activity compared to pristine nickel foam and undoped LIG-Ni (u-LIG-Ni), with an onset potential as low as 0.127 V and a Tafel slope of 64 mV/dec. The coating exhibits excellent durability and desirable bubble evolution. Overall, the proposed CoP-LIG-Ni fabrication process is simple, cost-effective, and scalable, thus advancing nickel-foam-based water electrolysis and material-incorporation technologies.