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Macroscale superlubricity breakdown of lubricating materials caused by substrate surface roughening and mechanochemical modification poses great challenges for their practical tribological applications. Here, a facile way is reported to access robust macroscale superlubricity in a vacuum environment, via the operando formation of graphene/transition‐metal dichalcogenide (TMDC) heterostructures at wear‐induced rough surfaces. By trapping active amorphous carbon (a‐C) wear products between TMDC flakes, the sandwich structures readily transform into graphene/TMDC heterostructures during running‐in stage, based on shear‐induced confinement and load‐driven graphitization effects. Then they assemble into multipoint flake‐like tribofilms to achieve macroscale superlubricity at steady stage by reducing contact area, eliminating strong cross‐interface carbon–carbon interactions and polishing a‐C rough nascent surface. Atomistic simulations reveal the preferential formation of graphene/TMDC heterostructures during running‐in stage and demonstrate the superlubric sliding of TMDCs on the graphene. The findings are of importance to achieve robust superlubricity and provide a good strategy for the synthesis of other van der Waals heterostructures.

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Triboelectric nanogenerators (TENGs) have attracted great interests in the development of sustainable energies and intelligent society. However, a big challenge for TENGs in practical applications is the unavoidable external mechanical abrasion and/or contaminant adsorption on the triboelectric materials, which leads to the significant decrease of the durability of TENGs and is urgently needed to be addressed. There are already a series of interesting progresses on the topic of the TENGs' durability. In this study, reviewing the durability of TENGs via both the advanced materials/structure designing and the novel surface/interface engineering is focused upon, which includes choosing basic TENG materials, improving composites performance, optimizing structures, and designing triboelectric surfaces and interfaces. To get a better understanding of the durability of TENGs in published studies, the quantifiable levels of service life are also summarized including operation cycles, time, friction coefficient, and wear loss of triboelectric materials, where the boosting mechanisms are also discussed and summarized. Finally, the challenges as well as key strategies toward high durable TENGs are presented.

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