Unraveling how mid-gap state energy level of graphitic carbon nitride (g-C₃N₄) promote near-infrared (NIR) driven photochemical energy conversion at the molecular level remains a grand challenge. Here, we report a series of S double-site-doped ultrathin g-C₃N₄ nanosheets (SUCN) with adjustable intermediate band gap benefits from light response over NIR region. The SUCN produced after optimizing S double-site doping can effectively generate hydrogen (H₂) under NIR-light irradiation. The highest H₂ generation rate achieved was respectively 9.35 and 17.46 μmol g⁻¹ h⁻¹ under λ = 765 and λ > 800 nm, which is firstly expended photocatalytic activity of S-doped g-C₃N₄ to NIR region beyond λ > 765 nm. We proposed a molecular-level method, i.e., the localized oxidation state of proton acceptor triethanolamine (TEOA) in the mid-gap state to ensure the NIR-driven H₂ generating behavior.

_{揭示石墨碳氮化物 (gC 3} N ₄ )的中带隙能级如何在分子水平上促进近红外 (NIR) 驱动的光化学能量转换仍然是一个巨大的挑战。在这里，我们报告了一系列 S 双位点掺杂超薄 gC ₃ N ₄纳米片 (SUCN)，其中间带隙可调节，受益于 NIR 区域的光响应。优化S双位点掺杂后生成的SUCN在近红外光照射下可有效产生氢气(H _{2 )。}在λ  = 765 和λ下，实现的最高 H ₂生成率分别为 9.35 和 17.46 μmol g ⁻¹ h ⁻¹ > 800 nm，这是首次将S掺杂gC ₃ N _{4的光催化活性扩展到}λ  > 765 nm以外的NIR区域。我们提出了一种分子水平的方法，即质子受体三乙醇胺 (TEOA) 在中间带隙状态下的局部氧化态，以确保 NIR 驱动的 H ₂生成行为。