Synergetic Confinement\nand Electron-Catalysis Boost\nN<sub>2</sub> Hydrogenation in C<sub>70</sub>F<sub>70</sub> Nanoreactor:\nA Theoretical Investigation

Reduction by one-electron activation or hydrogenation\nof N<sub>2</sub> is extraordinarily difficult because of its extremely\nstable\ntriple bond and symmetry-forbidden direct H<sub>2</sub> addition.\nDemonstrated herein is reduction or hydrogenation of N<sub>2</sub> in perfluorocarbon cage C<sub>70</sub>F<sub>70</sub>, a promising\nnanoreactor with synergetic confinement and electron-catalyzing effects.\nC<sub>70</sub>F<sub>70</sub> pointing all dipolar C–F units\ntoward its center not only traps reactants but also gives the cage\nand its guest species strong electron-hosting/binding abilities through\nlowering their orbital energies. Such a confinement effect can force\none electron into the N<sub>2</sub> π*-orbital, not only activating\nthe NN bond but also making its frontier molecular orbitals\nsymmetry matching with H<sub>2</sub> and thus boosting its hydrogenation\nwith a noticeable lowering of the energy barrier. The ability to initiate\nreduction reactions by absorbing electrons into the cage-reactor without\nsurface adsorption and solid catalysts enables pathways that are not\naccessible using conventional electro-/photochemical processes.