Graphene-like two-dimensional layered materials have attracted quite a lot of interest because of their sizable band gaps and potential applications. In this work, monodisperse tin disulfide (SnS2) nanosheets were successfully prepared by a simple solvothermal procedure in the presence of polyvinylpyrrolidone (PVP). Large PVP molecules absorbing on (001) facets of SnS2 would inhibit crystal growth along [001] orientation and protect the product from agglomeration. The obtained SnS2 nanosheets have diameters of ca. 0.8-1 μm and thicknesses of ca. 22 nm. Different experiment parameters were carried out to investigate the transformation of phase and morphology. The formation mechanism was proposed according to the time-dependent experiments. SnS2 nanosheets exhibit high photocatalytic H2 evolution activity of 1.06 mmol h(-1) g(-1) under simulated sunlight irradiation, much higher than that of SnS2 with different morphologies and P25-TiO2. Moreover, the as-obtained SnS2 nanosheets show excellent photoelectrochemical response performance in visible-light region.

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We report the solvothermal synthesis of hierarchical structures of orthorhombic Sb2WO6 and their implementation as a visible-light-driven photocatalyst for the degradation of Rhodamine B. The obtained hierarchical structures constructed by tiny nanosheets are doughnut-like flat ellipsoids with concaves in the centres, and with typical sizes of 1.3 μm in length, 800 nm in width and 400 nm in thickness. The concave characteristics and sizes of Sb2WO6 hierarchical structures can be tuned by adjusting the volume ratio of EG-H2O. Time-dependent experiments reveal that the formation process of concave structures involves the aggregation of nanoparticles to form solid spheres, dissolution-recrystallization to form hierarchical structures subsequently, and an Ostwald ripening process to shape the desired concaves finally. Under visible-light irradiation, complete degradation of Rhodamine B is achieved within 180 min in the presence of Sb2WO6 hierarchical structures, which could be ascribed to the porous structures, high BET surface area (42.58 m(2) g(-1)) and wide absorption in the visible-light region.

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By coating active titanium, Sn0.3Ag0.7Cu (SAC) filler wetted SiC effectively, as the contact angle decreased significantly from ~145° to ~10°. Ti3SiC2 and TiOx (x ≤ 1) reaction layers were formed at the droplet/SiC interface, leading to the reduction of contact angle. Reliable brazing of SiC was achieved using titanium deposition at 900°C for 10 minutes, and the typical interfacial microstructure of Ti‐coated SiC/SAC was SiC/TiOx + Ti3SiC2/Sn(s,s). Comparing to direct brazing, Ti–Sn compounds in the brazing seam were effectively reduced and the mechanical property of joints was dramatically improved by titanium coating. The optimal average shear strength of SiC joints reached 25.3 MPa using titanium coating‐ assisted brazing, which was ∼62% higher than that of SiC brazed joints using SAC‐Ti filler directly.

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