MoS shows promising applications in photocatalytic water splitting, owing to its uniquely optical and electric properties. However, the insufficient light absorption and lack of performance stability are two crucial issues for efficient application of MoS nanomaterials. Here, Au nanoparticles (NPs)@MoS sub-micrometer sphere-ZnO nanorod (Au NPs@MoS -ZnO) hybrid photocatalysts have been successfully synthesized by a facile process combining the hydrothermal method and seed-growth method. Such photocatalysts exhibit high efficiency and excellent stability for hydrogen production via multiple optical-electrical effects. The introduction of Au NPs to MoS sub-micrometer spheres forming a core-shell structure demonstrates strong plasmonic absorption enhancement and facilitates exciton separation. The incorporation of ZnO nanorods to the Au NPs@MoS hybrids further extends the light absorption to a broader wavelength region and enhances the exciton dissociation. In addition, mutual contacts between Au NPs (or ZnO nanorods) and the MoS spheres effectively protect the MoS nanosheets from peeling off from the spheres. More importantly, efficiently multiple exciton separations help to restrain the MoS nanomaterials from photocorrosion. As a result, the Au@MoS -ZnO hybrid structures exhibit an excellent hydrogen gas evolution (3737.4 μmol g ) with improved stability (91.9% of activity remaining) after a long-time test (32 h), which is one of the highest photocatalytic activities to date among the MoS based photocatalysts.

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Carbon nanomaterials have been widely used as an interlayer for realizing efficient and stable perovskite solar cells (PSCs). Theoretically, the design of a carbon composite interlayer that combines excellent conductivity with a high specific surface area is a better strategy than the application of pure nanocarbons. Here, an unusual seamlessly bonded carbon nanotube@ graphene (CNT@G) hybrid nanomaterial was strategically synthesized and demonstrated to behave as an efficient interlayer for realizing efficient and stable PSCs. Due to the advantage of the seamless bond, the as-proposed hybrid nanostructure showed an apparent improvement compared to the use of CNTs only, graphene only, or a simple mixture of CNTs and graphene. The power conversion efficiency improved from 15.67% to 19.56% after introduction of the hybrid nanomaterial due to efficient carrier extraction, faster charge transport, and restrained carrier recombination. More importantly, PSCs with a CNT@G hybrid-decorated hole transport layer (HTL) showed good thermal stability during a 50 h heat-aging test at 100 °C and water stability under ambient humidity (30-50% relative humidity) for 500 h because the hybrid nanostructure exhibited an increased capability to block ion/molecule diffusion. Our results provide an alternative approach for fully exploring the potential application of nanocarbons in the development of high-performance PSCs.

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Planar perovskite solar cells (PSCs) represent a promising alternative to solar cells due to their many advantages. To improve device performance, it is necessary to develop PSCs with good interfacial engineering and film crystallinity, which are two critical aspects of high‐performance PSCs. However, both aspects are relatively independent and difficult to simultaneously enhance. This study reports an effective and universal sequential solution deposition process to specifically address this issue. When the top layer of the hole‐transport material (HTM) is deposited from the dimethylsulfoxide (DMSO) cosolvent, the HTM penetrates a predeposited bottom layer of perovskite (the light‐absorption layer) during the spin‐coating process, resulting in an interdiffusion structure with layer‐evolved nanomorphology. In addition, the cosolvent DMSO captures vacant perovskite CH3NH3+ groups at the boundaries of perovskite grains, resulting in the growth of large‐sized grains. Compared to a conventional device, this new design realizes enhanced optical absorption, reduced crystal defects in perovskite film, tight contact, and well‐matched energy‐level alignment between the perovskite film and the hole‐transport layer (HTL). This strategy enables the fabrication of PSCs with enhanced short‐circuit current density (Jsc), fill factor (FF), and open circuit voltage (Voc), resulting in an enhanced power conversion efficiency (PCE) of 19.40% from 15.29% under standard testing conditions. This sequential deposition represents a feasible route for the preparation of high‐performance PSCs with spontaneous improvements in film quality and interfacial engineering for photovoltaic applications.