In　the　design　of　photocatalysts　for　ammonia　synthesis,　the　construction　of　effective　nitrogen　(N2)　adsorption　and　activation　sites　is　critical.　Herein,　Fe　single　atoms　were　effectively　fixed　on　the　surfaces　of　WO2.72-x　nanowires.　Electronic　interactions　between　single　Fe　atoms　and　WO2.72-x　resulted　in　a　d-band　center　shift　toward　the　Fermi　level　and　thus　enhancement　of　N2　bonding　with　the　catalyst　surface.　The　studies　of　differential　charge　density　and　electron　localization　reveal　that　there　is　enhanced　electron　transfer　from　Fe-SA/WO2.72-x　to　the　adsorbed　N2,　signifying　that　Fe　single　atoms　are　active　centers　for　N2　activation.　Benefiting　from　electronic　interactions,　the　optimized　catalyst　shows　a　NH4+　generation　rate　of　186.5　μmol　g-1　h-1　during　photocatalytic　N2　reduction.　©　2022　American　Chemical　Society.