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The general moderate reaction condition in solar photocatalytic hydrogen production (i. e., near ambient pressure, room temperature) makes interfacial mass and energy transfer extremely slow, even by employing a cocatalytic material (usually in the form of noble metal nanoparticles or their counterparts). Herein, by fabricating well‐defined Cu@Ni core‐shell nanoplate cocatalyst and further incorporating it with a g‐C3N4 photocatalyst, we demonstrate that interfacial processes could be significantly improved by coupling localized photothermal effect into a cocatalyst. Specifically, Cu nanoplate can induce localized strong hot spots on Ni nanoparticles via a visible‐light‐driven surface plasma resonance effect. As a result, photogenerated electrons transferred from g‐C3N4 to Ni, could be elevated to a more energetic state, leading to a substantially improved photocatalytic activity toward H2 evolution from water. The highest hydrogen generation rate reaches 55 μmol h−1 g−1, 110 times of that pristine g‐C3N4. This work indicates that photoelectric and photothermal effects can be effectively coupled by integrating metal hetero‐nanoparticles. [ABSTRACT FROM AUTHOR]

Developing high‐efficiency yet low‐cost photocatalyst for solar hydrogen production by avoiding the use of noble metals has received adequate interest but remains a great challenge to date. This work reports a seed‐mediated hydrothermal approach for the synthesis of NiS2 quantum dots (QDs) anchored two‐dimensional graphitic carbon nitride (g‐C3N4) nanosheets. This hybrid shows superior performance toward photocatalytic H2 evolution from water. The highest H2 evolution rate reaches 4.841 μmol h−1, with an apparent quantum efficiency of 2 % at 425 nm, which is even much higher than that of Pt‐modified g‐C3N4 photocatalyst (2.865 μmol h−1). Moreover, the composite presents good stability without notable activity decay after several cycled tests. It is found that NiS2 QDs are essential for this improvement. These small nanoclusters not only benefit rapid and vectorial diffusion of photogenerated electrons from g‐C3N4 to NiS2, but also promote H2 evolution by decreasing the thermodynamic overpotential for proton reduction. This work thus marks an important step toward designing good‐performance and low‐cost photocatalytic materials for solar H2 conversion. Quantum on the dot: NiS2 quantum dot successfully anchored on the surface of g‐C3N4 promotes both vectorial charge diffusion and rapid proton reduction during photocatalytic water splitting. [ABSTRACT FROM AUTHOR]