Enhanced N2 production via 3D electrocatalytic nitrate reduction on Pd-Cu SACs by P-doped bamboo biochar

The rapid expansion of industrial and agricultural activities has led to severe nitrate pollution in aquatic systems, threatening both human health and ecological balance. To address this challenge, we developed phosphorus-doped biochar-supported Pd-Cu dual single-atom catalysts (Pd-Cu@PBC). As three-dimensional (3D) particle electrodes, Pd-Cu@PBC achieved exceptional nitrate removal (>99% NO₃ ^--N within 3 h), representing a 7.27-fold enhancement over conventional 2D electrocatalytic systems, while maintaining high N₂ selectivity (46.68%) and a low energy barrier (8.32 eV) for the N-to-N₂ conversion pathway. Furthermore, density functional theory calculations confirmed that P-doping induces lattice distortion and surface curvature, which stabilizes the Pd-Cu single atoms; the catalyst also maintained over 90% activity after three reuse cycles. This work provides an efficient dual-SAC design strategy and a sustainable solution for advanced nitrate remediation.