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In this work, nanosheet-shaped CuS (NS CuS) is successfully grown on carbon cloth (CC) by a two-step route in combination with electrodeposition and hydrothermal treatment via in situ sulfidations of Cu2O and Cu with exposure to thiourea at 120 °C or 24 h. Transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffractometry are performed to characterize the microstructure, morphology, composition, and crystal structure of the NS CuS CC samples. The electrochemical measurements demonstrate that the synthesized NS CuS CC electrocatalysts possess outstanding oxygen evolution reaction (OER) performance and superior long-term durability in 1 M KOH electrolyte. In particular, the NS CuS CC synthesized via the electrodeposition process at an applied current of 1.5 mA shows a low overpotential for the OER (358 mV at 10 mA/cm2), which is close to that of commercial IrO2 (346 mV at 10 mA/cm2). The exceptional OER property is ascribed to the NS CuS having a large surface area to offer abundant reaction active sites and to the CC network structures supplying more ions and charge transfer channels during the electrocatalytic process.

We report a successful fabrication of low-cost, high-efficient, structurally-rigid, porous WO3 photoelectrochemical (PEC) catalysts using polystyrene as the template by a sol-gel method and a high-temperature annealing treatment. The scanning electron microscopy and Brunauer-Emmett-Teller surface analysis results indicate that such WO3 monoliths possess a porous structure and a large specific surface area, which can supply lots of photogenerated charge transfer pathways as well as more surface PEC active sites. Compared with a commercially available WO3, our highly porous WO3 PEC catalysts show an excellent PEC water splitting activity. Particularly, the porous WO3 photoanodes calcinated in the presence of oxygen atmosphere at 450 °C for 7 h show the best PEC performance exhibiting the photocurrent density of 0.97 mA/cm2 at 1.23 V versus reversible the hydrogen electrode and the incident photon-to-current conversion efficiency up to 48.9% at 420 nm in 0.5 M Na2SO4 electrolyte under AM 1.5 G irradiation. Such excellent PEC performance is due to the high porosity of the WO3, promoting the fast transfer and the separation rate of photogenerated carriers during the PEC water splitting process.

In this paper, the authors take the turfy soil in east Jilin province of China as the research object to make the analysis and conclusion on the frost heaving characteristics of the turfy soil foundation based on the indoor experiment. The study shows that the frost heaving rate is quite higher at the superficial layer of the turfy soil foundation but is slightly lower at the deep layer; the biggest frost heaving rate has a close connection with load, position, frozen depth and moisture content. Therefore, for the road construction, it is necessary to make a reasonable design and construction according to its characteristics, so as to prevent the roads in the turfy soil areas from generating diseases.