Synergistic Contact-Electro-Catalysis and Photocatalysis via TiO₂@PTFE Composites for Efficient N₂ to NH₃ Conversion

Catalytic nitrogen fixation from N₂ and water under mild conditions offers a sustainable NH₃ synthesis route. Herein, we report a synergistic nitrogen fixation strategy combining contact-electro-catalysis (CEC) with photocatalysis via one-step in situ hydrothermally synthesized TiO₂ @PTFE catalyst, and achieved an activity of 133.6 µmol g^-1 h^-1. It represents 10.9-fold and 7.5-fold enhancements over pristine TiO₂ and PTFE, respectively, outperforming current CEC systems and many photocatalytic systems operating without sacrificial agents. Further characterization and theoretical calculations reveal the synergy: the composite catalyst enhances the CEC catalyst dispersion; the CEC-generated electric fields promote photogenerated charge separation and elevate the semiconductor's Fermi level, bolstering photocatalytic N₂ reduction; conversely, the semiconductor boosts CEC efficiency via enhanced N₂ adsorption and supplemental electron donation. We anticipate that this work establishes a "two birds with one stone" strategy, providing novel insights into CEC-photocatalysis synergy and a pathway for rational design of high-performance nitrogen fixation catalysts.