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Two-dimensional (2D) materials have drawn tremendous attention due to their planar nature, good mechanical, optical and electrical properties especially for flexible electronic devices whose performance could be modulated by external mechanical strains. Here, the piezoresistive property of layered ReSe 2 upon various homogeneous strains is investigated. Highly sensitive and reliable response in resistance has been observed for ReSe 2 -based flexible devices under tensile/compressive strains. Photoluminescence spectra measurement further confirmed the strain modulation on the band gap energy, leading to the piezoresistive property in ReSe 2. Additionally, it is found that the electromechanical behavior of ReSe 2 can be greatly influenced by the directions of applied strains, where the gauge factor is 4.29 times higher when the strain is applied along the b -axis than that obtained under strain perpendicular to b -axis. The strain-direction-sensitive electromechanical behavior can be attributed to the different band gap change induced by strains along various directions. These results can contribute to the design, performance improvement and application development of flexible electronic devices based on anisotropic 2D materials. • ReSe 2 -based flexible devices were fabricated on PEN substrate for electromechanical measurement. • Piezoresistive property in ReSe 2 -based flexible devices showed high sensitivity, repeatability and long-term stability. • Strain-dependent photoluminescence spectra further revealed that the band gap energy change with strain was −16.65 meV/%. • The piezoresistive property of ReSe 2 was observed to be strain-direction sensitive. [ABSTRACT FROM AUTHOR]

The precise control of nitrogen doping types in carbon materials is crucial for optimizing energy storage devices. In this study, we synthesize nitrogen-doped carbon nanosheets (NCS) using ZIF-L as a precursor. Comparatively, the two-dimensional crystal structure of ZIF-L provides several advantages over ZIF-8 as a precursor in terms of nitrogen doping efficiency, achieving a higher doping level (14.56 %) and an increased ratio of pyridinic nitrogen (53.60 %). Consequently, NCS display a greater capacity for pseudocapacitive lithium storage. Furthermore, by adjusting the carbonization temperature, we precisely tailor the graphite-nitrogen doping level of NCS within the range of 16.80–31.22 %. Remarkably, when employed as an anode material in lithium-ion batteries, NCS-800 demonstrates exceptional cycling stability, with a capacity retention of 1078 mAh g−1 after 500 cycles at a current density of 0.5 A g−1, as well as excellent rate capability (735 mAh g−1 at 5 A g−1). This study not only compares the impact of precursor crystal structure modifications on nitrogen doping and lithium storage performance but also introduces a novel synthesis methodology for highly nitrogen-doped carbon materials, offering new avenues for future research in this field. • Nitrogen-doped carbon nanosheets (NCS) with a high nitrogen content using 2D ZIF-L as a precursor were synthesized. • The N level of NCS (14.56%) was higher than that of NCP (9.66%) obtained from ZIF-8 and tailored by heating temperature. • NCS-800 exhibited a specific capacity for lithium storage of 1078 mAh g‐1 after 500 cycles at 0.5 A g‐1 current density. [ABSTRACT FROM AUTHOR]

In this study, we have successfully developed a series of low-cost, environmentally friendly, and high-performance carbon-based conductive inks with a three-dimensional micro-nano structure through a simple dispersion and ball-milling process, offering an array of desirable characteristics. Significantly, the carbon-based conductive inks remained stable even after a 30-day settling period. Furthermore, the conductive film, produced using screen printing techniques, demonstrated an impressive conductivity of 1.99 × 103 S/m. This remarkable conductivity highlights the ability of the films to consistently maintain a robust conductivity network, even when subjected to 5000 mechanical bending/releasing tests. Expanding on the success of our carbon-based conductive inks, we harnessed their potential in the production of all-solid-state flexible Micro-supercapacitors (MSCs) with an interdigital structure, utilizing screen-printing technology. The resulting MSCs exhibited outstanding performance metrics, including a notable areal energy density of 1.47 µWh cm-2 and an area power density of 0.2 mW cm-2. Moreover, these MSCs demonstrated remarkable cycle stability, retaining 96.3% of their capacitance after 20,000 cycles. Additionally, their excellent mechanical flexibility was evident as they experienced only a minor 2.98% capacitance degradation after undergoing 5000 bending/releasing cycles. These findings highlight the enormous potential of our work in facilitating the scalable production of wearable and portable electronic products. • Synthesize a high-performance aqueous carbon-based ink. • Carbon black was attached to graphite flakes to construct an effective three-dimensional micro-nano structure. • The ink was applied in the field of planar micro-supercapacitors with screen printing technology, showing good electrochemical performances and excellent mechanical flexibility. [ABSTRACT FROM AUTHOR]

Iron-based catalysts have garnered great attention as alternatives for Fenton-like catalysts in the degradation of organic compounds. However, there is a demand for the synthesis of highly efficient iron-based catalysts that can solve the problems of iron dissolution and poor stability. Herein, nitrogen-doped graphitic carbon-supported Fe-Co/Fe 3 C dual active sites catalyst (Fe-Co/Fe 3 C-NC) is successfully prepared by ball milling method combined with subsequent high-temperature self-reduction. 0.5 wt%-Fe-Co/Fe 3 C-NC shows high efficiency in the activation of peroxymonosulfate (PMS) for the ultrafast degradation of high concentration Rhodamine B (200 mg/L of RhB is completely degraded within 8 min and the degradation rate constant is as high as 0.5066 min−1), as well as high stability and good reproducibility, attributing to the synergistic mechanism between the dual active sites (Fe-Co and Fe 3 C) and the adsorption sites (Fe 3 C and pyrrolic-N). Chemical quenching experiments and electron paramagnetic resonance indicate that the prepared 0.5 wt%-Fe-Co/Fe 3 C-NC exhibits outstanding activation for PMS by generating reactive oxygen species (SO 4 •−, •OH, 1O 2) and high-valent FeCo=O species. This work shows useful insights into the synthesis of iron-based dual active sites catalysts, providing exciting chances for the highly efficient degradation of high concentration organic wastewater. [Display omitted] • Successful synthesis of Fe-Co/Fe 3 C-NC using ball milling method combined with high-temperature self-reduction. • Fe-Co/Fe 3 C-NC shows high efficiency and stability in the activation of PMS for the degradation of RhB. • The superior degradation performance is attributed to the synergistic effect between the active and adsorption sites. • The outstanding activation of Fe-Co/Fe 3 C-NC for PMS ascribes SO 4 •− and 1O 2 species and high-valent FeCo=O. [ABSTRACT FROM AUTHOR]

Although widely used as conducting substrates for solar cells, indium-tin oxide-based (ITO) electrodes' potential for improvement of visible light transmittance is frequently overlooked of perovskite solar cells (PSCs) as most work focuses on the improvement of the working components (e.g., light absorber, etc) of the solar cells. This work shows a great improvement on solar cell performance by increasing the transmittance (up to 94 %) of the SnO 2 /ITO electrode through adjusting the refractive index of the SnO 2 with D -arginine monohydrochloride (D -Arg) and introducing extra amino group, carboxyl groups and chloride ions to passivate interface defects. A 21.74 % of the championship power conversion efficiency is obtained, in comparison to the 19.58 % of the control device, and an increase in the short-circuit current from 23.26 to 24.51 mA cm−2. Long-term stability is demonstrated with more than 86 % retention rate of the initial when stored in an air environment (10 % −25 % RH, 25 ℃), for 720 h. Therefore, this work provides a new and general approach in improving the performance of PSCs. [Display omitted] • D-arginine monohydrochloride (D-Arg) enhances device efficiency (19.58 % to 21.74 %) and long-term stability. • The modification increases the visible light transmittance of the SnO 2 /ITO electrode (up to 94 %). • An effective D -Arg is applied to PSCs, which simultaneously improve the quality of perovskite film and SnO 2 ETL. PSCs benefit from D-Arg application, improving the quality of perovskite film and SnO2 ETL. • This modification has successfully promoted energy level alignment. [ABSTRACT FROM AUTHOR]

Poor cyclic stability and low rate capability are two severe stumbling blocks for Co 3 O 4 -based anodes due to the insufficient structural stability of the electrode, difficult access of electrolyte to the electrode interior as well as dense structure. In this respect, one-dimensional hierarchically porous Co 3 O 4 nanorods (HP-Co 3 O 4 NR), which are constructed by interconnected nanoparticles, are successfully synthesized via a facile hydrothermal method following calcination. In the architecture, (i) nanoparticle-decoration is favorable to shorten the ions and charge diffusion distance, which improve the rate performance; (ii) the hierarchically porous structure can sufficiently buffer the volume change during the extended cycling, which is conducive to stable electrode structure and good cyclic stability; (iii) 1D porous nanorods ensure more exposed active sites and the contact area of the electrolyte/electrode for lithium storage, which endows the high reversible capacity. As a result, the HP-Co 3 O 4 NR material exhibits high capacity (628 mAh g −1 at 1 A g −1 after 350 cycles), exceptional rate capability (247 mAh g −1 at 6 A g −1 ) and long cycle life (0.068% capacity decay per cycle after 600 cycles at 5 A g −1 ), simultaneously. Our results indicate that the one-dimensional hierarchically porous nanoparticle-decorated nanorods structure is beneficial for improving the cycling and rate performance. [ABSTRACT FROM AUTHOR]

Zinc selenide (ZnSe) has recently developed into an appealing semiconductor material for visible-light-driven photocatalytic H 2 production due to its suitable band gap and superior stability. However, constructing ZnSe-based hybrid systems to improve charge separation and photocatalytic performance remains challenging. Herein, Co 2 P/ZnSe composites are synthesized by a facile in-situ solvothermal method for efficient H 2 production via photocatalytic water splitting. The optimized 8.4% Co 2 P/ZnSe composite displays an excellent H 2 production rate of 2799 μmol g−1 h−1, exceeding that of pristine ZnSe by a factor of 4.2. The significant improvement in the photocatalytic H 2 reaction of Co 2 P/ZnSe composites is attributed to the formed intimate interfaces through the in-situ growth of ultrafine Co 2 P onto ZnSe. At the same, Co 2 P can act as a profitable cocatalyst coupled with ZnSe to promote the separation and transfer of photogenerated charge carriers. This work brings valuable insights into the preparation and photocatalytic mechanism of ZnSe anchored with metal phosphide, which may be further extended to other solar energy conversion systems. [Display omitted] • Co 2 P/ZnSe heterostructures were fabricated via a facile in-situ solvothermal method. • Ultrafine Co 2 P nanoparticles serve as a profitable cocatalyst to promote the separation efficiency of photo-induced charges. • Co 2 P/ZnSe showed a significant improved photocatalytic H 2 activity compared with pristine ZnSe. • A feasible photocatalytic mechanism of Co 2 P/ZnSe heterojunction was proposed. [ABSTRACT FROM AUTHOR]

Abstract: Mg–Nd coatings were prepared by high-energy micro-arc alloying (HEMAA) on AZ31 magnesium alloy. The coatings were treated with Ar shielding gas in ambient atmosphere. X-ray diffraction (XRD) results showed that the phases formed of Mg–Nd coatings were similar to that of Mg–Nd electrode. The corrosion behavior of the coated AZ31 in 3.5wt% NaCl solutions was studied by simple immersion test and potentiodynamic polarization measurement. It was found that the corrosion resistance of coated alloy was higher than that of AZ31 substrate. The corrosion potential of Mg–Nd coatings was much positive to that of AZ31 substrate. Furthermore, the corrosion resistance is bad due to the presence of defects when treated with undesired processing parameters. [Copyright &y& Elsevier]