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The inferior tribological properties of titanium (Ti) and its alloys, due to their limited work hardening capability and the mechanical instability of their oxide scale, pose substantive challenges in practical applications. Surface texturing and the application of 2D material coatings are acknowledged as efficacious strategies for enhancing these properties. Nevertheless, the rapid loss of effectiveness when employing these methods in isolation highlights a significant limitation. Herein, a 50‐nm‐thick MXene nanocoating is deposited onto groove‐textured pure Ti surface, effectuating a reduction in the coefficient of friction (COF) from ≈0.57 to 0.17, thereby substantially mitigating wear on the Ti substrate. The grooved surface architecture plays a vital role in storing MXenes and facilitating lubricant replenishment through the stirring effect of frictional stress during subsequent friction process. Further, the continuous decomposition and reorganization of MXene coating results in the formation of a robust tribofilm that resists oxidation and plastic deformation in the subsurface layer, markedly enhancing the friction and wear resistance. These findings are crucial for improving tribological performance in Ti and its alloys and provide a straightforward yet effective strategy for tailoring their tribological properties by integrating LST with 2D material nanocoating. [ABSTRACT FROM AUTHOR]

MXene, notable for its excellent electrical conductivity and tunable surface groups, has garnered widespread attention in the field of electrochemical energy storage. Here, Ti3C2Tx MXene was synthesized by a Lewis acid molten salt‐shielded synthesis (MS3). The surface groups (−Cl, −O) were modified by washing Ti3C2Tx samples with various solutions (deionized water, 0.5 M hydrochloric acid (HCl), 0.5 M ammonium persulfate solution (APS)) and/or thermal treatments under an argon atmosphere at 300 °C, 500 °C, and 700 °C. It is shown that deionized water and HCl solution washing have minimal impact on the surface groups, while APS washing can increase the content of −O surface group. Conversely, thermal treatment may remove the −O. Electrochemical charge storage behavior of these Ti3C2Tx variants were further investigated in a 1 M acetate electrolyte buffered at pH=5.0. It is indicated that the −Cl surface group is electrochemically inert, whereas the −O may significantly improve the charge storage performance. Ti3C2Tx with high −O content delivered an impressive maximum capacity of 155 C g−1. This research underscores the crucial role of surface groups on the electrochemical performance of Ti3C2Tx in mild aqueous electrolytes, offering valuable insights for future modifications and applications of Ti3C2Tx in energy storage technologies. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐bromine batteries represent a promising large‐scale energy storage system, yet generally suffer from the dissolution of polybromides in the cathode. Currently, various nonpolar carbon materials are employed as hosts for the bromine cathode. Still, they typically exhibit weak adsorption capabilities toward polybromides. Here, a highly conductive Ti2CTx MXene synthesized through an eco‐friendly molten salt method is reported, serving as an ideal bromine cathode host material for the first time. Ti2CTx MXene shows strong chemisorptive capability to soluble polybromide species and can effectively immobilize them for enhanced coulombic efficiency and prolong cycling life of zinc‐bromine batteries. Additionally, Ti2CTx MXene enhances the reaction kinetics of the bromine cathode. Benefiting from the synergistic polybromide adsorption and catalysis effects of Ti2CTx, the dual‐plating zinc‐bromine batteries exhibit good cycle stability, with a capacity retention of 87% after 3000 cycles, outperforming traditional carbon host which fail after 2300 cycles. Meanwhile, Ti2CTx achieves a much lower polarization voltage of only 84 mV, significantly less than 240 mV observed with carbon hosts. This research highlights the potential of developing host materials with polybromide chemisorptive properties to advance the performance of zinc‐bromine batteries. [ABSTRACT FROM AUTHOR]

An organic bipolar polymer electrode called poly[anthraquinone‐alt‐dihydrophenazine] (PAD) is in situ synthesized between the two‐electron n‐type unit of dibromoanthraquinone and two‐electron p‐type unit of dihydrophenazine on the layered MXene nanosheets, leading to the formation of the material composition called PAD@MX. PAD@MX shows almost the same redox mechanism and electrode performance in Na/K‐based batteries. In Na/K‐based half cells, PAD@MX can show the peak discharge capacities of 240/255 mAh g−1 and peak energy densities of 511/597 Wh kg−1, respectively, which are among the top results for cathodes in the world. Furthermore, the Na/K‐based dual‐ion symmetric batteries can be simultaneously constructed by using PAD@MX as the single electrode material. Both symmetric batteries fulfill the "ready‐to‐charge" property without any pre‐activation. Therein, PAD@MX delivers the reversible discharge capacities of 86/104 mAh g−1cathode and energy densities of 54/64 Wh kg−1total mass, stably running for 500 cycles. To the best of our knowledge, this is the first example of organic bipolar electrodes simultaneously applied to the Na/K‐based dual‐ion symmetric batteries in the world. [ABSTRACT FROM AUTHOR]

In response to antibiotic residues in the water, a novel advanced oxidation technology based on MgO2 was used to remediate sulfamethazine (SMTZ) pollution in aquatic environments. Upon appropriate regulation, the remarkable removal efficiency of SMTZ was observed in a UV/MgO2 system, and the pseudo-first-order reaction constant reached 0.4074 min−1. In addition, the better performance of the UV/MgO2 system in a weak acid environment was discovered. During the removal of SMTZ, the pathways of SMTZ degradation were deduced, including nitration, ring opening, and group loss. In the mineralization exploration, the further removal of residual products of SMTZ by the UV/MgO2 system was visually demonstrated. The qualitative and quantitative researches as well as the roles of reactive species were valuated, which revealed the important role of ·O2−. Common co-existing substances in actual wastewater such as NO3− HA, Cl−, Fe2+, Co2+, and Mn2+ can slightly inhibit the degradation of SMTZ in the UV/MgO2 system. Finally, the capacity of efficient degradation of SMTZ in actual wastewater by the UV/MgO2 system was proved. The results indicated that the innovative UV/MgO2 system was of great practical application prospect in antibiotic residue wastewater remediation. [ABSTRACT FROM AUTHOR]

Objective To discuss whether there are differences in fingerprint ridge density between the males and the females and what the specific differences are. Method A total of 120 males and 120 females (all were college students in Fujian) were selected, and the fingerprint ridge densities of these 240 Han youths were counted. According to Acree method, the radial upper part of the core region of the fingerprint center was selected for analysis, because the fingerprint pattern types in this region all presented similar ridges. This method was used to isolate the ridge in a certain area, so as to facilitate the counting. A 5mm×5mm grid was designated as a counting area on the middle radial part of the fingerprint for identification. Fingerprint ridges in the unit area were counted, then the average was calculated, and finally SPSS software was used to process and analyze all the data obtained. Result For the females, the average ten-fingerprint ridge density was basically above 14 ridges/ 25mm2; and for the males, it was basically below 14.5 ridges/25mm2. Conclusion There are some differences in the density of ten-fingerprints between men and the females, and the females’ is generally higher than that of the males.