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Hydrogen gas (H2) is a promising energy cartier and an impor-tant chemical feedstock for industrial processes [1].A facile and atom-economic hydrogen storage strategy is markedly significant for hydrogen utilization.The currently prevailing mechanically compressed/cryogenic technologies or unstable metal-hydride methods are facing serious issues on high cost,safety risk,complex procedures,and special apparatus [2].In contrast,the liquid organic hydrogen carriers (LOHCs) system has alternatively pro-vided an efficient and promising approach toward hydrogen stor-age,in which a pair of H2-rich and H2-1ean organic compounds can repeatedly uptake and release H2 through the reversible for-mation and cleavage of the covalent X-H (X =C,N,O,etc.) bonds[3,4].Early LOHCs studies focused on the hydrogenation of aromat-ics and the reverse dehydrogenation of cycloalkanes,which suf-fered from using noble metal catalysts,harsh reaction conditions(reaction temperature usually ＞250 ℃),and the intrinsic toxic-ity/carcinogenicity of benzene and toluene molecules [5,6].To solve these concerns,N-heterocycles with a decreased enthalpy of hydrogenation/dehydrogenation were developed as a good alternative for implementing H2 storage.Despite these important advances in LOHCs,most researches required the use of noble metal catalysts at high temperatures to activate the organic mole-cules and H2 for loading and unloading H2 (Fig.1a).Besides,the catalysts and solvents were usually varied for both hydrogenation and reversible dehydrogenation processes,which further added the cost and complexity for H2 storage.Thus,it is highly desirable to develop a room-temperature N-heterocycle-based LOHCs sys-tem over a non-noble metal catalyst,especially using low-cost and safe water as the hydrogen source.