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Ni–Co–BN (h) nanocomposite coating was prepared by jet electrodeposition (JED) under different temperatures. The surface morphology, element composition, crystal structure, microhardness and corrosion resistance of the samples prepared at different temperatures were analyzed and characterized by scanning electron microscope (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD), microhardness tester, electrochemical workstation, respectively. The experimental results showed that the micro-protrusions on the sample surface gradually changed from spherical to diamond with the variation of the temperature, and the consistency of the micro-protrusions was improved. The coating thickness and the Co content of the samples first increased and then decreased with the change of the temperature. The deposition temperature changed the gain size of the samples, but it had no obvious effect on the crystal structure. The crystal structure of all the samples was still face centered cubic (fcc) structure. When the temperature was 60°C, the sample had better performances in the microhardness and the corrosion resistance. Under this parameter, the average value of the microhardness reached 608.5 HV0.05, the corrosion current density was 0.54 μA/cm2, and the corrosion rate was 6.51 μm/year. [ABSTRACT FROM AUTHOR]

AbstractConveyor belts are used for material transportation in the mining and construction industries. The friction and wear properties of the styrene butadiene rubber (SBR) used in conveyor belts are investigated, including the effects of the applied load and rotational speed on the friction coefficient and weight loss. The sliding wear mechanism of the SBR is analyzed using scanning electron microscope, energy dispersive spectrometer, and Fourier transform infrared spectrometer. The results demonstrate that the friction coefficient and total weight loss of SBR increase as a function of rotational speed, whereas the friction coefficient decreases and the total weight loss increases as a function of increasing applied load. The maximum friction coefficient occurred at a loading of 10 N and a speed of 120 revolutions·min−1, and the maximum total weight loss occurred at a loading of 20 N and a speed of 120 revolutions·min−1. In comparison to the unworn surface, the worn surface of the SBR exhibits melting, adhesive, and abrasive wear characteristics. The increases in the hardness, yellowing, oxygen content, and the number of complex structures, such as hydroxyl, aldehyde, ketone, and ether groups, occur simultaneously. [ABSTRACT FROM AUTHOR]

Recently, it has been reported that MXene is a promising pseudocapacitive material for energy storage, primarily due to its intercalation mechanism. However, Ti3C2Tx MXenes face challenges, such as inadequate layer spacing and low specific capacity, which greatly hinder their potential as anode materials for sodium storage. In this study, MXene was doped with sulfur to create a three-dimensional porous structure that resulted in an increased layer spacing. The sulfur-doped porous MXene (SPM) demonstrated exceptional performance as sodium ion battery anodes, with a capacity of 335.2 mA h g−1 after 490 cycles at 2 A g−1 and a long-term cycling performance of 256.1 mA h g−1 even after 2480 cycles at 5 A g−1. It is worth noting that the porous structure formed after sulfur-doping exhibits superior sodium storage performance compared to previously reported MXene-based electrodes. This highlights the feasibility of the structural construction strategy, offering an effective solution for energy storage and conversion applications. [ABSTRACT FROM AUTHOR]

Recently, lead halide perovskites have been developing rapidly in the field of photo-electric functional devices. The key to further enhancing its potential in thin-film photo-electronic devices lies in understanding the charge (electron/hole) separation process and its transfer across the interface. In addition to optimizing the preparation conditions, finding excellent electron/hole transport materials is a matter of priority for improving the efficiency of charge separation between different functional layers in optoelectronic devices. In this work, a novel organic metallic functionalized ferrocenyl acetylacetone (FAAT) derivative was developed as a hole transport material (HTM). The very stable lead halide perovskite material and CsPbBr3 quantum dots are used as carrier donors, and data from TRPL show that the addition of FAAT can improve the carrier separation efficiency at the quantum dot interface by at least 64.6%. Moreover, the excited state dynamics data from transient absorption experiments also show that the excited state dynamics of quantum dots rapidly change from the fluorescence relaxation process (2440 ps) to the hole transfer process (263 ps) after the addition of FAAT. FAAT was used as a dopant-free HTM to improve the photovoltaic performance of the inverted perovskite solar cells (PSCs). As a result, the optimal FAAT-based device efficiency reached 19.05%. All these studies indicate that FAAT is expected to be a cost-effective and chemically stable hole transport material for efficient PSCs. [ABSTRACT FROM AUTHOR]

In this study, Ni–Co–Al2O3–SiC nanocomposite coatings with varying concentrations of Co were electrodeposited in a modified watts bath using conventional electrodeposition technique. The microhardness, surface morphology and phase structure of the coatings were characterized using Vickers microhardness tester, scanning electron microscopy and X-ray diffraction, respectively. The corrosion resistance of the composite coating was evaluated in 3.5% NaCl solution using an electrochemical work station. Increase in Co concentration in the electrolyte resulted in an increase in the microhardness of the nanocomposite coating. Corrosion resistance of coatings was also seen to increase considerably with increase in Co concentration in electrolyte. This was attributed mainly to the decrease in grain size, chemical composition, phase structure and preferred orientation of the coatings. The increase in Co in the electrolyte had a significant effect on the crystallite size of the Ni–Co–Al2O3–SiC coatings. [ABSTRACT FROM AUTHOR]

Exploring anode materials with an excellent electrochemical performance is of great significance for supercapacitor applications. In this work, a N-doped-carbon-nanofiber (NCNF)-supported Fe3C/Fe2O3 nanoparticle (NCFCO) composite was synthesized via the facile carbonizing and subsequent annealing of electrospinning nanofibers containing an Fe source. In the hybrid structure, the porous carbon nanofibers used as a substrate could provide fast electron and ion transport for the Faradic reactions of Fe3C/Fe2O3 during charge–discharge cycling. The as-obtained NCFCO yields a high specific capacitance of 590.1 F g−1 at 2 A g−1, superior to that of NCNF-supported Fe3C nanoparticles (NCFC, 261.7 F g−1), and NCNFs/Fe2O3 (NCFO, 398.3 F g−1). The asymmetric supercapacitor, which was assembled using the NCFCO anode and activated carbon cathode, delivered a large energy density of 14.2 Wh kg−1 at 800 W kg−1. Additionally, it demonstrated an impressive capacitance retention of 96.7%, even after 10,000 cycles. The superior electrochemical performance can be ascribed to the synergistic contributions of NCNF and Fe3C/Fe2O3. [ABSTRACT FROM AUTHOR]

• The novel CdS/CuInS 2 /polymer planar heterojunction hybrid solar cells are designed. • The polymer absorption range and charge mobility affect remarkably the device performance. • Polymer layer acts as complementary absorber and selective extractor of holes. This study reports the fabrication of a new planar heterojunction hybrid solar cell using CuInS 2 /polymers (MEH-PPV, P3HT and PCE10) as the composite donor and CdS as the acceptor. The main absorber layer in planar hybrid heterojunctions is CuInS 2 film, while the polymer film facilitates complementary absorption and selective hole extraction. The impact of charge mobility and absorption range of polymer film on the device performance was examined. Since PCE10 outperforms MEH-PPV and P3HT in terms of hole mobility and has superior absorption complementarity with the CuInS 2 film, PCE10-based hybrid cell showed significantly improved J sc and FF and achieved a remarkable power conversion efficiency of 5.35%. [ABSTRACT FROM AUTHOR]

The use of renewable and environmentally friendly biomass to prepare carbon materials with a hierarchical porous structure and large specific surface area has attracted great attention in energy storage devices (Supercapacitors, SCs). Here, a succulent-leaf-derived carbon material with a hierarchical porous structure (N-S-HPC) was prepared through a one-step carbonization strategy using Mg(NO 3) 2 ·6H 2 O and ZnCl 2 as double activation agents and CH 4 N 2 S as S and N source. The N-S-HPC specific capacitance reached 455.3 F g−1 at 1 A g−1, and with 1 M Na 2 SO 4 electrolyte. The assembled N-S-HPC//N-S-HPC symmetric SCs could enhance the voltage window to 1.8 V. Meanwhile, N-S-HPC exhibited the specific energy of 19.89 Wh kg−1 (450 W kg−1) and highly stable cycling performance. Compared with previously reported biomass-derived carbon materials, N-S-HPC has the advantages of i) hierarchical porous sturcture and 2136.2 m2 g−1 maximal specific surface area, allowing accommodation of more ions; ii) 1177.5 m2 g−1 specific surface area for mesopores and macropores, providing shorter diffusion pathways; iii) rich co-doping of N (9.5 at. %) and S (2.21 at. %), increasing pseudocapacitive contribution and improving surface wettability. All these data indictae the great potential application prospect of N-S-HPC, suggesting the importance of biomass-derived carbon materials for symmetric SCs. [Display omitted] • N-S-HPC derived succulent plant leaves was prepared by a dual-activating agents (ZnCl 2 and Mg(NO 3) 2 ·6H 2 O) approach. • N-S-HPC displays an ultra-high specific capacitance, due to its a large specific surface area and rich N/S co-doping. • N-S-HPC exhibit an excellent supercapacitive properties and excellent cycling stability. [ABSTRACT FROM AUTHOR]