The effect of substitutional and interstitial doping on the electronic structure and surface adsorption plays an important role in tuning physical and chemical properties. Herein, boron-doped NiCo2S4 (B-NiCo2S4) was designed and prepared for high rate and long-term stability supercapacitors, considering the substitutional and interstitial boron (Bsub and Bint) doping due to similar atomic size. The low conductivity and slow reaction kinetics of NiCo2S4 hampered its rate performance and weak cycle stability for energy storage devices. After boron doping, B-NiCo2S4 can promote electron transfer to improve rate performance and increase surface adsorption energy to capture the electrolyte ion due to electronegativity difference during the charge/discharge process. Furthermore, the contribution of Bsub and Bint doping modes can be elucidated by density functional theory calculations. The density of states of B-NiCo2S4 (26.7 eV–1) was much higher than that of NiCo2S4 (6.2 eV–1) near the Fermi level resulting from Bsub doping. The doping-induced charge transfer was enhanced by adjusting the position of the Fermi level. Bint doping redistributed the surface charge, resulting in increased OH– adsorption and then improved Faradaic reaction kinetics in alkaline electrolyte. This research strategy implements the research of synergistic promotion of theoretical prediction and experimental verification very well.

Metal–support interaction (MSI) is considered a key effect of electronic and geometric structures of catalysts on tuning catalytic performance. The oxygen evolution reaction (OER) is a crucial process during energy conversion and storage. However, the OER process requires the help of noble metal catalysts to reduce the reaction overpotential, enhance reactivity with intermediates, and maintain good operating stability. Carbon–supported metal catalysts have been considered candidates for noble metal catalysts for OER. MSI occurs at the interface of carbon supports and metals, affecting the catalytic performance through electronic and geometric modulation. MSI can influence the catalytic performance and change reaction pathways from charge redistribution, electron transfer, chemical coordination and bonding, and steric effect. Connecting MSI effects with the OER mechanism can provide theoretical guidance and a practical approach to the design of efficient catalysts, including the modulation of particle size, morphology, heteroatom doping, defect engineering, and coordination atom and number. Advantage can be taken of MSI modulation between metal compounds and carbon supports to provide guidance for catalyst design.