摘要：The interaction between a gas molecule and photocatalyst is vital to trigger photocatalytic *** surface state of photocatalyst affects much in this ***,adsorption of H2O molecules on s-triazine-based g-C3N4 was thoroughly studied by first-principle *** various initial adsorption models with multifarious locations of H2O molecules were built,the optimized models with strong adsorption energy pointed to the same adsorption configuration,in which the H2O molecule hold an upright orientation above the corrugated g-C3N4 *** intermolecular O-H…N hydrogen bond formed via the binding of a polar O-H bond in H2O molecule and a two-coordinated electron-rich nitrogen atom in *** the bridging effect of this intermolecular hydrogen bond,electrons would transfer from g-C3N4 to the H2O molecule,thereby lowering the Fermi level and enlarging work function of ***,regardless of the substitute,i.e.g-C3N4 multilayer,large supercell and nanotube,this adsorption system was highly reproducible,as its geometry structure and electronic property remained *** addition,the effect of nonmetal element doping on adsorption energy was *** work not only disclosed a highly preferential H2O adsorbed g-C3N4 architecture established by intermolecular hydrogen bond,but also contributed to the deep understanding and optimized design in water-splitting process on g-C3N4-based photocatalysts.