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Because of their unique chemical and physical properties, inorganic semiconducting nanostructures have gradually played a pivotal role in a variety of research fields, including electronics, chemical reactivity, energy conversion, and optics. A major feature of these nanostructures is the quantum confinement effect, which strongly depends on their size, shape, crystal structure and polydispersity. Among all developed synthetic methods, the hydrothermal method based on a water system has attracted more and more attention because of its outstanding advantages, such as high yield, simple manipulation, easy control, uniform products, lower air pollution, low energy consumption and so on. Precise control over the hydrothermal synthetic conditions is a key to the success of the preparation of high-quality inorganic semiconducting nanostructures. In this review, only the representative hydrothermal synthetic strategies of inorganic semiconducting nanostructures are selected and discussed. We will introduce the four types of strategies based on exterior reaction system adjustment, namely organic additive- and template-free hydrothermal synthesis, organic additive-assisted hydrothermal synthesis, template-assisted hydrothermal synthesis and substrate-assisted hydrothermal synthesis. In addition, the two strategies based on exterior reaction environment adjustment, including microwave-assisted and magnetic field-assisted hydrothermal synthesis, will be also described. Finally, we conclude and give the future prospects of this research area.

We present a simple and effective heterogeneous contraction method to fabricate hollow spheres with controllable interior structures (ranging from solid, simple hollow to core-in-hollow-wall, double-wall hollow and core-in-double-hollow-wall spheres) by a non-equilibrium heat-treatment process of gel precursors with a high heating rate.

In this work, n-type porous graphite-like C3N4 (denoted as p-g-C3N4) was fabricated and modified with p-type nanostructured BiOI to form a novel BiOI/p-g-C3N4 p-n heterojunction photocatalyst for the efficient photocatalytic degradation of methylene blue (MB). The results show that the BiOI/p-g-C3N4 heterojunction photocatalyst exhibits superior photocatalytic activity compared to pure BiOI and p-g-C3N4. The visible-light photocatalytic activity enhancement of BiOI/p-g-C3N4 heterostructures could be attributed to its strong absorption in the visible region and low recombination rate of the electron-hole pairs because of the heterojunction formed between BiOI and p-g-C3N4. It was also found that the photodegradation of MB molecules is mainly attributed to the oxidation action of the generated O2˙(-) radicals and partly to the action of h(vb)(+)via direct hole oxidation process.

Impurity‐free single‐crystalline antimony telluride hexagonal nanoplates (see figure) are synthesized by a facile and quick hydrothermal treatment without any organic additives or templates. The inherent crystal structure is the driving force for the growth of these Sb2Te3 hexagonal nanoplates. Films of these nanoplates shows p‐type behavior, and exhibit a promisingly high Seebeck coefficient of 125 µV K−1 at room temperature.

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A thorough understanding of the effect of N doping on the oxygen evolution reaction (OER) is greatly significant for constructing next-generation electrocatalysts with an optimal configuration and high efficiency for the fuel cell. Herein, we reported the synthesis of N-doped CoS2 through a facile method using ammonium hydroxide as the N source, the subjection of N-doped CoS2 as efficient electrocatalysts for OER, and the identification of intrinsic activities by exploring the composition and electronic configurations and their correlations with the electrochemical performance. The DFT studies evidenced that N doping could alter the electronic density of the adjacent Co atoms and thus form well-defined electronic configurations for adsorption of intermediates. Specifically, the N-enriched CoS2 afford a small overpotential of 240 mV at the current density of 10 mA cm–2 and long-term durability, endowing these N-doped materials to be ideal (but not limited to) OER electrocatalysts.

A novel Ag/Bi3TaO7 plasmonic photocatalyst has been prepared by a simple photoreduction process. The as-prepared Ag/Bi3TaO7 photocatalyst exhibited an enhanced photocatalytic activity for the degradation of tetracycline (TC) compared to that of a bare Bi3TaO7 catalyst. The 1 wt % Ag-loaded Bi3TaO7 sample showed the highest photocatalytic efficiency for TC degradation (85.42%) compared with those of the other samples. The enhanced photocatalytic activity could be ascribed to the synergistic effect of the surface plasmon resonance caused by Ag nanoparticles. Electrochemical impedance spectroscopy demonstrated that the incorporation of silver nanoparticles onto the Bi3TaO7 surface promoted the separation of photogenerated carriers. In addition, an electron spin resonance (ESR) and trapping experiment revealed that the photoinduced active species hydroxyl radical and superoxide radical were the main active species in the photocatalytic process of TC degradation. The photocatalytic reaction mechanism was discussed by active species trapping and ESR analysis.