DFT-Guided Design and Synthesis of Nitrogen and Boron Dual-Doped Porous Carbon Catalyst Derived from Saccharina japonica for Oxygen Reduction Reaction

Abstract

Abstract The oxygen reduction reaction (ORR) is a critical process affecting the energy conversion efficiency of fuel cells. In this innovative study, six models were designed to showcase the superior ORR activity of nitrogen and boron dual-doped carbon (N, B dual-doped carbon) compared to N or B mono-doped carbon, as determined through density functional theory (DFT) calculations. Furthermore, a highly efficient N (4.63 at%), B (1.13 at%) dual-doped carbon ORR catalyst (S-850-1) was successfully synthesized from Saccharina japonica, which represents a rare achievement among biomass-derived carbon materials. Electrochemical analysis revealed a significant improvement in the half-wave potential (0.862 V) and limiting diffusion current density (-5.60 mA cm− 2) of S-850-1 compared to N mono-doped carbon (S-850: 0.839 V and − 5.24 mA cm− 2) in an alkaline solution. Additionally, S-850-1 exhibited enhanced durability and superior tolerance to methanol and CO, surpassing the performance of the commercial 20% Pt/C catalyst. Notably, S-850-1 was successfully incorporated into a Zn-air battery, generating an open circuit voltage of 1.40 V and effectively illuminating an LED light. The obtained electrochemical results were consistent with the DFT calculations, thereby confirming the high ORR activity of N, B dual-doped carbon in both theoretical and experimental domains. This groundbreaking research not only expands the range of biomass-derived ORR catalysts but also provides valuable insights into the design and synthesis of efficient and cost-effective catalysts derived from renewable sources.