Fe-N4-anchored Carbon Layer Patched TiO2 Cavities to Construct an "In-lattice Heterojunction" for Enhanced Photocatalytic Nitrogen Reduction Reactions.

Efficient charge separation and carrier transfer are critical determinants of the performance of photocatalysts for nitrogen reduction reactions (NRR) which are critical for agricultural and chemical industries. In this study, a novel type of heterostructure, termed an "in-lattice heterojunction", has been constructed by introducing a Fe-N4-anchored carbon layer (Fe-N-C) onto the surface of defective TiO2 (D-TiO2), as well as implanting it into the cavities of D-TiO2. The in-lattice heterojunction, defined as FNCTO, achieves efficient radial carrier transfer along the Ti-C-N-Fe in-lattice atomic channel and greatly promoted N2 adsorption benefiting photocatalytic NRR. Thus, FNCTO exhibits an excellent photocatalytic N2 reduction into NH3 activity (88 μmol g-1 h-1), obviously higher than that of Fe-N-C sites on non-cavity P25, illustrating the crucial role of cavity patch induced in-lattice heterojunction. This study paves a way for the development of high-performance Fe-N-C atomic photocatalysts based on non-carbon materials.