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Photocatalytic degradation is one of the most promising emerging technologies for environmental pollution control. However, the preparation of efficient, low-cost photocatalysts still faces many challenges. TiO2 is a widely available and inexpensive photocatalyst material, but improving its catalytic degradation performance has posed a significant challenge due to its shortcomings, such as the easy recombination of its photogenerated electron–hole pairs and its difficulty in absorbing visible light. The construction of homogeneous heterojunctions is an effective means to enhance the photocatalytic performances of photocatalysts. In this study, a TiO2(B)/TiO2(A) homogeneous heterojunction composite photocatalyst (with B and A denoting bronze and anatase phases, respectively) was successfully constructed in situ. Although the construction of homogeneous heterojunctions did not improve the light absorption performance of the material, its photocatalytic degradation performance was substantially enhanced. This was due to the suppression of the recombination of photogenerated electron–hole pairs and the enhancement of the carrier mobility. The photocatalytic ability of the TiO2(B)/TiO2(A) homogeneous heterojunction composite photocatalyst was up to three times higher than that of raw TiO2 (pure anatase TiO2). [ABSTRACT FROM AUTHOR]

Abstract: Few-layered ReS2 two-dimensional (2D) semiconductor nanosheets directly nucleated and grown on reduced graphene oxide (RGO) were synthesized through a facile hydrothermal method. Compared with bare ReS2, the ReS2/RGO hybrid delivers much better electrocatalytic activity for hydrogen evolution reaction (HER) in acidic media. It exhibits a lower Tafel slope of 107.4 mV·dec−1 and a larger current density of − 5.2 mA·cm−2 at − 250 mV (vs. RHE), compared with ReS2 (152.7 mV·dec−1, − 3.1 mA·cm−2). The ReS2/RGO hybrid has a unique architecture constructed by highly conductive and porous RGO internetworks, which guarantees easy electrolyte infiltration and efficient charge transfer and provides sufficient active edge sites, resulting in enhanced HER performance. The present synthesis approach can be extended to synthesize other 2D-semiconductor-based composites for energy storage and catalytic devices.Graphical abstract: [ABSTRACT FROM AUTHOR]

Effects of the interstitial carbon atoms on the magnetic properties, especially on the magnetic entropy change, of the LaFe[SUB11.5]Si[SUB1.5] compound, have been studied. X-ray diffraction patterns reveal a monotonous increase of the lattice constant with the concentration of carbon, while the cubic NaZn[SUB13]-type structure remains unchanged. The Curie temperatures T[SUBC] of LaFe[SUB11.5]Si[SUB1.5]C[SUBy] are ∼ 195, 225, and 241 K for y = 0, 0.2, and 0.5, respectively, increasing with the increase of carbon concentration. The maximal magnetic entropy changes ‖ΔS‖ of LaFe [SUB11.5]Si[SUB1.5]C[SUBy] at the respective T[SUBC] under a magnetic field change of 0-5 T are ∼24.6, ∼22.8, and ∼12.7 J/kg K for y50, 0.2, and 0.5, respectively, notably exceeding that of Gd (‖ΔS‖ ∼9.8 J/kg K at T[SUBC] = 293 K). The ‖ΔS‖ of LaFe[SUB11.5]Si[SUB1.5]C[SUB0.2] is nearly as giant as that of the parent alloy LaFe[SUB11.5]Si[SUB1.5] due to the first-order field-induced itinerant-electron metamagnetic transition that occurs in both compounds clearly observed for the LaFe[SUB11.5]Si[SUB1.5]C[SUB0.5] compound. With the increase of carbon concentration, the nature of magnetic transition has been changed from first order to second order, which results in the significant decrease of the magnetic entropy change. The large ‖ΔS‖, convenient adjustment of T[SUBC] and relatively low cost make the LaFe[SUB11.5]Si[SUB1.5]C[SUBy] interstitial compounds promising candidates for magnetic refrigerants in the corresponding temperature range. [ABSTRACT FROM AUTHOR]

Chemically stable LaFe[sub 11.6]Si[sub 1.4]C[sub x] (x = 0-0.6) interstitial compounds were prepared. The Curie temperatures increases from 195 to 250 K with an increase in X from 0 to 0.6 due to obvious lattice expansion. The maximal magnetic entropy changes ΔAS with a change in magnetic field of 0-5 T, are 24.8, 24.2, 18.8 and 12.1 J/kg K for x = 0, 0.2, 0.4, and 0.6, respectively, notably exceeding that of Gd (ΔS∼ 9.8 J/kg K at T[sub C] = 293 K). The magnetic transition varies from first order to second order with an increase in carbon concentration, which has a decisive influence on ΔS. The large ΔA, chemical stability, and low cost make LaFe[sub 11.4]Si[sub l.6]C[sub x] a promising candidate as a magnetic refrigerant in the corresponding temperature ranges. [ABSTRACT FROM AUTHOR]

Providing reliable communication represents one of the major barriers to wireless sensor networks. In this paper, we propose a fault-tolerant tableless routing protocol called E-cube+, inspired from e-cube routing protocol, to support intelligent rerouting. A range of fault-tolerant routing properties of E-cube+ (such as loop-freeness, failure recovery guarantees, and bounded latency) have been derived and analyzed. Experiment results also show that E-cube+ is able to route data properly without complicated and energy-intensive routing table lookup processes even when node failures occur. [ABSTRACT FROM AUTHOR]

The effects of 60Co γ-ray irradiation on the DC characteristics of AlGaN/GaN enhancement-mode high-electronmobility transistors (E-mode HEMTs) are investigated. The results show that having been irradiated by 60Co γ-rays at a dose of 3 Mrad (Si), the E-mode HEMT reduces its saturation drain current and maximal transconductance by 6% and 5%, respectively, and significantly increases both forward and reverse gate currents, while its threshold voltage is affected only slightly. The obvious performance degradation of E-mode AlGaN/GaN HEMTs is consistent with the creation of electronegative surface state charges in the source-gate spacer and gate-drain spacer after being irradiated. [ABSTRACT FROM AUTHOR]