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Engineering heterostructures of transition metal disulfides through low-cost and high-yield methods instead of using conventional deposition techniques still have great challenges. Herein, we present a conveniently operated and low-energy-consumption solution-processed strategy for the preparation of heterostructures of MoSe2nanosheet array on layered MoS2, among which the two-dimensional MoS2surface is uniformly covered with high-density arrays of vertically aligned MoSe2. The unique compositional and structural features of the MoS2–MoSe2heterostructures not only provide more exposed active sites for sequent electrochemical process, but also facilitate the ion transfer due to the open porous space within the nanosheet array serving as well-defined ionic reservoirs. As a proof of concept, the MoS2–MoSe2heterostructures serve as promising bifunctional electrodes for both energy conversions and storages, which exhibit an active and acid-stable activity for catalyzing the hydrogen evolution reaction, high specific capacity of 728 F g–1at 0.1 A g–1, and excellent durability with a remained capacity as high as 676 mA h g–1after 200 cycles.

Solar-driven water oxidation is the key step for overall water splitting that efficiently harvests and converts solar energy into fuels; the development of a highly efficient photocatalyst that can mediate water oxidation has become an appealing challenge. Herein, we report a facile two-step process to decorate silver phosphate (Ag3PO4) particles on different types of graphitic carbon nitrides (g-C3N4) as composite photocatalysts for water oxidation. For all the Ag3PO4/g-C3N4materials, an in situ Z-scheme is created by the generation of Ag nanoparticles which act as a cross-linking bridge between Ag3PO4and g-C3N4in the composite, resulting in better charge separation and higher catalytic performance. A detailed analysis emphasizes the importance of the g-C3N4on the chemical, photophysical, and catalytic properties of the composite materials. Our results show that the alteration of the morphology dominates the performance of the composite materials.

Herein, we report the use of upconversion agents to modify graphite carbon nitride (g-C3N4) by direct thermal condensation of a mixture of ErCl3·6H2O and the supramolecular precursor cyanuric acid-melamine. We show the enhancement of g-C3N4photoactivity after Er3+doping by monitoring the photodegradation of Rhodamine B dye under visible light. The contribution of the upconversion agent is demonstrated by measurements using only a red laser. The Er3+doping alters both the electronic and the chemical properties of g-C3N4. The Er3+doping reduces emission intensity and lifetime, indicating the formation of new, nonradiative deactivation pathways, probably involving charge-transfer processes.