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Although research progress on mimicking natural photosynthesis for solar-to-fuel conversion has been continuously made, exploring broadband spectral-responsive materials with suitable band positions and high stability still remains a huge challenge. Herein, we, for the first time, report novel AsP nanosheets (NSs) with P-type semiconducting property and enough negative conduction band, which can work as a stable near-infrared (NIR) region-responsive electron donor for water reductive hydrogen (H2) production. To mimic photosystem I, Au nanorods (NRs) act as electron transport media, which are also responsible for the enhanced electric field nearby, and 1T-MoS2NSs as a hydrogen evolution catalyst are orderly coupled with AsP NSs with a sheet-rod-sheet structure by electrostatic self-assembly. The cascaded band level alignment enables unidirectional electron flow from AsP to Au and then to MoS2, and the optimum H2production rate of the MoS2-Au-AsP ternary heterojunction reaches 125.52 μmol g–1h–1with good stability even after being stored for several months under light irradiation with a wavelength longer than 700 nm. This work provides a platform that is energetically tailored to drive a solar broad-spectrum fuel generation, including CO2reduction and N2fixation.

Monolayer MoS2nanosheets (NSs) are promising anode materials for lithium-ion batteries because all redox reactions take place at the surface without lithium-ion diffusion limit. However, the expanded band gap of monolayer MoS2NSs (∼1.8 eV) compared to their bulk counterparts (∼1.2 eV) and restacking tendency due to the van der Waals forces result in poor electron transfer and loss of the structure advantage. Here, a facile approach is developed to fabricate the MoS2–graphene aerogels comprising controlled three-dimensional (3D) porous architectures constructed by interconnected monolayer MoS2–graphene hybrid NSs. The robust 3D architectures combining with the monolayer feature of the hybrid NSs not only prevent the MoS2and graphene NSs from restacking, but also enable fast electrode kinetics due to the surface reaction mechanism and highly conductive graphene matrix. As a consequence, the 3D porous monolayer MoS2–graphene composite aerogels exhibit a large reversible capacity up to 1200 mAh g–1as well as outstanding cycling stability and rate performance, making them promising as advanced anode materials for lithium-ion batteries.

Increasing specific surface area and electrical conductivity are two crucial ways to improve the capacitive performance of electrode materials. Nanostructure usually enlarges the former but reduces the later; thus, it is still a great challenge to overcome such contradiction. Here, we report hydrogenated NiCo2O4double-shell hollow spheres, combining large specific surface area and high conductivity to improve the capacitive performance of supercapacitors. The specific surface area of NiCo2O4hollow spheres, fabricated via programmed coating of carbon spheres, was enlarged 50% (from 76.6 to 115.2 m2g−1) when their structure was transformed from single-shell to double-shell. Furthermore, activated carbon impedance measurements demonstrated that the low-temperature hydrogenation greatly decreased both the internal resistance and the Warburg impedance. Consequently, a specific capacitance increase of >62%, from 445 to 718 F g−1, was achieved at a current density of 1 A g−1. Underlying such great improvement, the evolution of chemical valence and defect states with co-increase of these two factors was explored through X-ray photoelectron spectroscopy. Moreover, a full cell combined with NiCo2O4and AC was assembled, and an energy density of 34.8 Wh kg−1was obtained at a power density of 464 W kg−1.