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Rational designing advanced materials with multicomponents and multiscale nanostructures is an important pathway to promote the rapid development and practical application of high-performance supercapacitors. Herein, FeCo2S4@Ni@graphene nanocomposites are prepared through electroless depositionhydrothermal two-step method. In this hybrid structure, the metal nickel as a conductive bridge significantly enhances the charge transport and the structural stability between FeCo2S4 and graphene by encouraging the heterogeneous nucleation of FeCo2S4 on the active Ni@graphene. More importantly, the rich defects are induced into FeCo2S4@Ni@graphene by the interface engineering due to the lattice mismatch at the interface between Ni and FeCo2S4 and partial substitution of Ni for Co or Fe. These defects can provide additional faradic redox reactions and abundant active sites. Benefiting from the synergies of above advantages, the optimized FeCo2S4@Ni@graphene shows a specific capacity of 390.0 mAh g–1 at 1 A g–1. Additionally, the asymmetric supercapacitor based on FeCo2S4@Ni@graphene delivers a high energy density of 65.8 Wh kg–1 at 849 W kg–1, as well as capacitance retention of 89.2% after 6000 cycles at 20 A g–1. This work proposes an effective strategy, which is to regulate the defects in transition-metal compounds through heterointerface engineering to prepare advanced energy-storage materials.

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Graphene-nickel (G-Ni) composites were in situ fabricated by a powder metallurgy method. The effects of graphene content on the tribological behavior of G-Ni composites were investigated. The tribochemistry and structural evolution of graphene were analyzed by X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy to understand the lubricating role of graphene in the G-Ni composite. The results show that graphene protects the nickel matrix from severe oxidation at the expense of its oxidation during sliding friction. Graphene on the friction interface transforms from a structure with less defects to a disordered amorphous structure. Polymeric segments are also generated by the tribochemical reactions of graphene. The formation of the tribofilms containing amorphous carbon and polymers is responsible for the self-lubricating behavior of the G-Ni composites.

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Objective To summarize the clinical and dermatoscopic features of temporal triangular alopecia in infants and explore the clinical significance of dermatoscopy in the diagnosis of triangular alopecia temporalis in infants. Methods A retrospective analysis was performed on 20 children with temporal triangular alopecia diagnosed in the dermatology clinic of Tianjin Children's Hospital from January 2015 to December 2021. Dermatoscopy was performed on all children, and images were collected. Results The clinical features of 20 children were 15 males and five females, all of which were born immediately after birth; There were eight cases (40%) in the left temporal region, 10 cases (50%) in the right temporal region, one case (5%) in the head region, and one case (5%) in the occipital region; 19 cases were single (95%), one case was multiple (5%); There were 21 skin lesions, 15 triangular lesions (71.4%), four quasi‐circular lesions (19%), and two lance‐shaped lesions (9.5%). Trichoscopic features: The hair follicle opening in all skin lesions is normal, and the hair follicle opening can be seen with fluffy hair (vellus hair). The vellus hair is evenly distributed, and the length is diverse (both short and long vellus hair exist in the same hair loss area). There are 14 cases of white vellus hair (70%), five cases of white spots (25%), one case of honeycomb pigment pattern (5%), and one case of vascular dilation pattern (5%). Conclusion Temporal triangular alopecia in infants has typical clinical and dermatoscopic characteristics, and the dermatoscopy can provide clinical basis for its diagnosis and differential diagnosis.