Robust electrocatalysts decorated three-dimensional laser-induced graphene for selective alkaline OER and HER

Morphological and functional modifications allow graphene to be applied as promising electrode support for improved electrochemical cell performance. Typically, however, modification requires complicated steps with various organic additives, such as binders, which causes low electrochemical stability, especially under harsh pH conditions. Herein, we introduce self-supported and long-term stable water splitting electrodes based on nanoparticles (NPs) decoration on three-dimensional porous laser-induced graphene (3D-LIG). A binder-free, single-step electrochemical process homogeneously decorates the 3D-LIG electrodes with CuO and Pt NPs, referred to CuO-3D-LIG and Pt-3D-LIG electrodes, respectively. These electrodes are individually analyzed for enduring oxygen evolution (OER) and hydrogen evolution (HER) activities. The porous wrinkled morphology of the 3D-LIG offers a large surface area and facilitates electrolyte influx within channels. Whereas strongly anchored CuO and Pt NPs enable highly stable electrochemical performances of the CuO-3D-LIG and the Pt-3D-LIG electrodes. The corresponding OER and HER overpotentials at 10 mA cm−2 (η10) are observed at 251 mV and 455 mV. These electrodes offer excellent electrochemical robustness in operationally challenging alkaline conditions (1 M KOH, pH ∼ 14) for extensive periods. In addition, we confirm the workable electrostatic interactions NPs – graphene via Becke-3-parameter Lee–Yang–Parr (B3LYP) model with 6-31G (d,p) and Stuttgart-Dresden (SDD) basis, which is supposed to be responsible for electrochemical durability and high current density yield of CuO-3D-LIG and Pt-3D-LIG electrodes. This study offers one of a few experiments to utilize decorated 3D-LIG for both OER and HER processes, assuming their substantial industrial potential in overall water splitting.