查看更多>>摘要：? 2022 Elsevier B.V.The publisher regrets the original article title “Enhanced thermoelectric performance of n-type (PbSe)n(Sb2Te3) pseudo-binary via Zn filling and Ag2Se compositing” shall be “Enhanced thermoelectric performance of n-type (PbSe)n(Sb2Se3) pseudo-binary via Zn filling and Ag2Se compositing” instead. The publisher would like to apologise for any inconvenience caused.
查看更多>>摘要：? 2022 Elsevier B.V.The sluggish oxygen evolution reaction (OER) kinetics on hematite (α-Fe2O3) has constrained the photoelectrochemical (PEC) performance for water oxidation. Considering the regulatory effect of Zn for electrocatalytic OER, the Zn doped α-Fe2O3 nanowire is successfully prepared and served as the photoanode for PEC water oxidation. The results reveal the theoretical overpotential for the limiting step (from OH* to O*) is decreased by ca. 320 mV after Zn doing, which indicates an incredibly improved catalytic performance of OER. The Zn doped α-Fe2O3 displays PEC performance improvement over the bare α-Fe2O3, photocurrent density increases up to 0.88 mA/cm2(1.23 VRHE, 1 M NaOH), which shows a 44-fold increase than the α-Fe2O3. Meanwhile, the onset potential also shifts negatively by 300 mV, which also agrees well with the decreased OER overpotential. This work provides a deep understanding of the role of Zn in the α-Fe2O3 photoanodes and the strategy could be extended to other photoactive systems.
查看更多>>摘要：? 2022 Elsevier B.V.The effective management of silicon kerf waste produced from silicon wafer cutting processes of photovoltaic industry is of great significance for environmental protection and resources recycle. High-purity silicon kerf waste collected by acid-assisted separation and purification can be recycled as silicon source of silicon-based anode for lithium storage. Although volume volatility and low conductivity rooted in silicon anode are effectively handled by constructing carbon coated silicon composite with porous structure, it is always impeded by a HF-involved synthesis process for etching SiO2 as template. Here, a green systhesis approach for porous carbon encapsulated recycled silicon kerf waste (Si@PC) are reasonably designed that calcium carbonate (CaCO3) constructed as sacrificial layer is effortlessly removed away by HCl-assisted pickling, leaving porous structure. When evaluated in LIBs, the discharge capacity keeps at 712.6 mAhg?1 after 200th cycle at 0.5 Ag?1, whose initial capacity reaches to 2739.2 mAhg?1; Meanwhile, it demonstrates a significantly improved rate performance. In brief, this work provides a green and low-cost method to synthesize high-performance silicon/carbon composite with porous structure as anode for lithium storage based on recycled silicon kerf waste, meanwhile offers a new viewpoint for the effective management of silicon kerf waste from photovoltaic industry with high value.
查看更多>>摘要：? 2022 Elsevier B.V.The design and synthesis of efficient and earth-abundant nonprecious metal electrocatalyst for oxygen evolution reaction (OER) plays a vital role in electrocatalytic water splitting. Here, amorphous NiFe layered double hydroxide (LDH) nanosheets deposited on Fe doped Ni3S2 nano-ridges (Fe-Ni3S2 @NiFe LDH) are successfully synthesized through a simple hydrothermal-electrodeposition method and are applied as OER electrocatalysts. In addition, benefiting from the abundant electroactive sites, electronic effect induced by Fe-doping and synergistic effect between NiFe LDH and Fe-Ni3S2, the as-prepared Fe-Ni3S2 @NiFe LDH heterogeneous catalyst can exhibit excellent OER performance in 1.0 M KOH solution. Fe-Ni3S2 @NiFe LDH only reach an overpotential of 192 mV at the current density of 10 mA cm? 2 with a Tafel slope of 43.1 mV dec?1. Notably, as-obtained Fe-Ni3S2 @NiFe LDH electrocatalyst only requires a low overpotential of 217 mV to achieve a current density of 50 mA cm? 2. And Fe-Ni3S2 @NiFe LDH also exhibits excellent durability at 50 mA cm?2 in 1.0 M KOH at room temperature. This study provides a feasible approach for the design of highly efficient earth-abundant nonprecious metal electrocatalysts for OER.
查看更多>>摘要：? 2022 Elsevier B.V.Cesium lead halide perovskite crystals have attracted widespread attention due to their excellent photoelectric properties. However, their intrinsic instability and the photoluminescence quantum yield (PLQY) sharply dropped in the solid-state limit their practical applications. Besides, the current synthesis strategies either need a variety of ligands, or an anti-solvent, which will result in potential environmental risks. Herein, we address the above issues simultaneously by embedding CsPbBr3 in a large bandgap Cs4PbBr6 matrix by high-speed mechanical mixing without using any ligands and highly toxic anti-solvent. Changing the molar ratio of PbBr2/CsBr, centrifugation time, and the solution concentration, the optimized CsPbBr3/Cs4PbBr6 show a high PLQY of up to 79%. In addition, mechanistic studies show that the origin of green luminesce of CsPbBr3/Cs4PbBr6 microcrystals is closely related to the CsPbBr3 inclusion theory, but not to the Br vacancy theory, in which CsPbBr3 embedded in Cs4PbBr6 to form a CsPbBr3/Cs4PbBr6 heterostructure. By taking advantage of the heterostructure, the photostability and thermostability of CsPbBr3/Cs4PbBr6 are significantly enhanced. In addition, the high optical and temperature/humidity-stable performances of CsPbBr3/Cs4PbBr6 are verified by applying them to white LEDs (WLEDs). The electroluminescence intensity of WLEDs remains 70% of the original one after being stored in a chamber with high temperature and high humidity (85 °C/RH 85%) for 40 h, and the device displays luminous efficiency of 74.5 lm/W at 20 mA. This result provides a solid foundation for their scale applications in lighting, displays, and other optoelectronic and photonic devices.
查看更多>>摘要：? 2022 Elsevier B.V.Mechanical spectroscopy measurements were performed on ionic liquids (ILs) with quaternary cations, either ammonium or phosphonium, and two anions, bis(trifluoromethanesulfonyl)imide ([NTf2]-) and bis(trifluoromethanesulfonyl)methanide ([CHTf2]-), which have almost the same molecular weight and degree of fluorination but exhibit different flexibility. Furthermore, the effect of multiple ether functionalization was studied by measuring the mechanical spectrum of [P(2O2)31][CHTf2]. The measured data evidence the occurrence of a relaxation process in the liquid phase of the ILs with flexible [NTf2]- anion and of [P(2O2)31][CHTf2], which is analyzed by means of a modified Debye model relating the peak to the ion hopping between non-equivalent configurations. The analysis confirms the involvement of nonequivalent anion configurations as well as their energy separation. For other ILs having rigid ions, instead, a fast dynamic at local level in the liquid phase is rarely observed since a partial transition to a solid state is favored. For these liquids, the measurements suggest the formation of aggregates which is suppressed by the multiple ether functionalization.
查看更多>>摘要：? 2022 Elsevier B.V.Electrolytic water splitting offers a prodigious amount of hydrogen and oxygen production, which could satisfy the demand for clean energy for building the community of human destiny. Thus, as the key technology barrier, the development of a low-cost and high-performance bifunctional transition metal electrocatalyst toward water splitting is still a challenge. In this work, aiming to enhance electrocatalytic performance, the nickel molybdenum nitride heterostructure nanowire arrays were synthesized on nickel foam (Ni3N-Mo2N/NF) via hydrothermal strategy followed by a direct nitridation, from which the heterostructure nanowire was achieved. The self-supporting Ni3N-Mo2N/NF electrodes exhibits very low overpotentials of 66 and 252 mV at 10 mA cm?2 for the hydrogen evolution reaction and oxygen evolution reaction, respectively. When the cathode and anode were both Ni3N-Mo2N/NF, a current density of 10 mA cm?2 was achieved with only 1.55 V. This work provides a new idea for the design and preparation of non-precious metal-based transition metal nitride catalysts.
查看更多>>摘要：? 2022 Elsevier B.V.In this paper, the fabrication of Cu2O-CuO/TiO2 nanocomposite photocatalysts on Cu wire was performed successfully via chemical-thermal oxidation and sol-gel process. The chemical-thermal oxidations were applied for Cu2O-CuO nanostructure fabrication on the Cu wire surface. The sol-gel process was utilized for TiO2 nanoparticles decoration as a surface modification process for photocatalytic activity improvement. The X-ray diffraction analysis (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS) showed the coexistence of multiple components including Cu2O, CuO, Cu, and TiO2 in the nanocomposite. Field emission electron scanning microscopy (FESEM) results demonstrated remarkable changes in morphology by applying different preparation conditions. The calculated band gap energies from UV–vis diffuse reflectance spectra (DRS) were in the range of 1.72–1.96 eV demonstrating their activity under visible light illumination. Photoluminescence (PL) data indicated delayed recombination of electrons - holes with surface modification due to the formation of heterostructure in the nanocomposite. The investigation of the photocatalytic performance was performed by methylene blue (MB) and methylene orange (MO) dye degradation under visible light illumination and 87 % degradation efficiency was obtained after 120 min. The active species trapping tests involving scavengers demonstrated that the superoxide radicals and holes play more noticeable roles compared to hydroxyl radicals in photocatalytic degradation. The ability to easily separate photocatalyst wires from aqueous solution along with good stability after several cycles of use in degradation is a unique feature of the prepared photocatalysts.
查看更多>>摘要：? 2022The excellent electromagnetic wave (EMW) absorption performance of metal organic frameworks (MOFs) has attracted a lot of attention. In this work, zeolitic imidazolate framework-67 (ZIF-67) was synthesized hydrothermally using 2-methylimidazole (2-mIm) as the organic ligand, cobalt nitrate hexahydrate (Co(NO3)2·6H2O) as the cobalt source and methanol (MeOH) as the organic solvent. The ZIF-67 was etched with cerium nitrate hexahydrate (Ce(NO3)3·6H2O), leading to rhombic dodecahedron Ce–Co/C composites with porous hollow structure after thermal annealing. In addition, the effect of the content of Ce(NO3)3·6H2O on EMW absorption performance of the Ce–Co/C composites was studied. Specifically, the sample Ce–Co/C-2 (Ce(NO3)3·6H2O): (ZIF-67 = 1:2) showed optimal EMW performance. For the Ce–Co/C-2 based composite with a filling ratio of 45 wt%, a RLmin reached ?64.67 dB at 11.12 GHz with a thickness of 2.21 mm. The promising EMW absorption performance of the porous hollow structure was attributed to its large specific surface area and massive defects, multiple reflection/scattering, improved impedance matching and increased dielectric loss. This work provides a reference improve EMW absorption performance of MOF materials through regulating their microstructures.
查看更多>>摘要：? 2022 Elsevier B.V.Aiming at fabrication of cellular metallic glasses with high mechanical properties, double edge notched samples were designed by orthogonal design method. Compressive tests on those samples were carried out to investigate mechanical responses induced by different notch settings. It was found that the notch tip distance and stress triaxiality are two key factors controlling yield strength and plasticity of notched samples. Besides, free volume theory factoring in hydrostatic stress was incorporated into finite element model to simulate shear band (SB) deformation process for different samples. Combined with experiments, simulations as well as microstructure observations, it was concluded that the notch tip distance effect could be ascribed by transition process between sparsely-intersected and densely-intersected SBs, and the later is the key to plasticity enhancement. Additionally, large stress triaxiality could improve the global plasticity by introducing densely-intersected SBs so as to hinder sample from fracturing along one major SB. The current work could offer useful data in providing direct evidence on fabrication of cellular materials as well as enriching shear band formation mechanism of monolithic metallic glasses.
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