The interfacial interaction in the In2S3@Bi2S3 vdW heterostructure is beneficial for transferring photogenerated holes to the surface with efficient water oxidation.

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High energy and efficient solar charging stations using electrochemical capacitors (ECs) are a promising portable power source for the future. In this work, two kinds of metal‐organic framework (MOF) derivatives, NiO/Co3O4 microcubes and Fe2O3 microleaves, are prepared via thermal treatment and assembled into electrochemical capacitors, which deliver a relatively high specific energy density of 46 Wh kg−1 at 690 W kg−1. In addition, a solar‐charging power system consisting of the electrochemical capacitors and monocrystalline silicon plates is fabricated and a motor fan or 25 LEDs for 5 and 30 min, respectively, is powered. This work not only adds two novel materials to the growing categories of MOF‐derived advanced materials, but also successfully achieves an efficient solar‐ECs system for the first time based on all MOF derivatives, which has a certain reference for developing efficient solar‐charge systems.

The development of efficient and stable non-noble-metal electrocatalytic materials for the oxygen evolution reaction (OER) is a huge and important challenge at present.

sluggish four electrons transfer process. [4] Two-dimensional (2D) materials present the advantages of a short exciton diffusion distance and a thickness less than the width of the space charge region at solid/liquid interfaces, thus potentially serve as the excellent photoanodes. [5,6] Indium sulfide (In 2 S 3) is a broad-spectral 2D material with ordered vacancy spinel-like structure, the sulfide anions are closely packed in layers, with octahedral-coordinated In cations present within the layers, and tetrahedralcoordinated In cations between them. [7,8] 2D In 2 S 3 is an n-type semiconductor with small size effect, exhibiting large surface area when its size is of nanometers, exposing a high percentage of edges that could produce active surface toward catalytic reaction. The variation of size in nanometer scale could also tune the bandgap based on quantum size and surface effect. [9,10] The common approaches to the fabrication of 2D In 2 S 3 include chemical vapor deposition, hydrothermal, solvothermal, and solgel process, however, precise controlling the dimensions of this compound is still difficult and have not been reported. [11,12] Fortunately, in a solvothermal reaction, the size and shape of the products could be controlled by nucleation and subsequent growth. The homogeneous nucleation limits the formation of nucleation sites and quantity attributing to the diversity of surface energy and nucleation barrier. [13] In 2 S 3 was fabricated by the former researchers usually leads to the large multilayer flakes, [8,14] whereas a lower surface energy can make it easier to grow on seed sites. Therefore, seed-mediated growth has a good control of nucleation density, and thus attaining uniform structure with desired edges. Introduction of alien atoms to 2D material is an effective way for tuning electrical and optical properties of the host material via orbital hybridization. [15] The Fermi level E F of most n-type semiconductors can be tuned by introducing impurity doping which is capable of causing dramatic changes in their interlayer electrical structure. [16-18] Once the position of hybridized impurity level is near the E F or valence band, it becomes the electrons or holes trap center (e.g., P-CdS and Gd-BiVO 4) and then affects the charge separation. [19-21] The doping pattern of the impurity species in the host materials include interstitial and substitutional sites. If an impurity atom is located in the gap between atoms in the lattice, it often refers to an interstitial doping, whereas an impurity atom substitute at the position of metal or chalcogen

Hematite (Fe2O3) can be suitable when used in a solar energy conversion system, but the short charge diffusion lengths limit its applications. Here, we report the studies of charge transfer ability with a 40 nm Fe2O3 nanorod decorated by a 5 nm iron phosphide (FeP) core–shell structure. By selecting the optimized time of phosphorization (20 min), the photocurrent of FeP@Fe2O3-20 photoanode reached 0.86 mA/cm2, enhanced by 4.10-fold compared with pristine Fe2O3 (0.21 mA/cm2) for water oxidation. Further, the charge transport time reduced by 30% due to the FeP shell that served as the hole transport layer. Compared with Fe2O3, FeP@Fe2O3 has a higher Fermi level, which guides the electron’s transfer from FeP to Fe2O3 to create a space charge layer. The charge balance induces an upward bending of band structure at the FeP and Fe2O3 interface and accelerates the separation of photogenerated electron–holes ascribed to the built-in electric field at the interface. Our studies provide a detailed understanding of carrier dynamics in the core–shell structure, demonstrating a new route to explore high efficiency approaches for solar harvesting.