Lubricant delivery and transfer-film formation govern friction and wear in enclosed sliding contacts, yet these buried interfacial processes are difficult to monitor. Oil-loaded microcapsules can supply lubricants to self-lubricating fabric composite liners, but their release behavior is usually optically silent. Here, we report an optically self-reporting microcapsule strategy for AF/PTFE fabric composites, in which dodecyl-chain-modified carbon quantum dots (CQDs-C₁₂) were dispersed in PAO4 and encapsulated in SiO₂ microcapsules as fluorescent lubricant reservoirs. During ball-on-disk sliding, local contact stresses triggered the release of CQDs-C₁₂/PAO4 into the wear track. The normalized integrated fluorescence area provided a semi-quantitative optical indication of the cumulative release and accumulation of the fluorescent lubricant phase. The optimized CD–MCs /Fabric achieved a friction coefficient of 0.085 and a wear volume of 1.03 × 10^-10 m³, which were 61.7% and 44.5% lower than those of Pure Fabric, respectively. SEM/EDS, Raman, XPS and cross-sectional FIB-TEM analyses confirmed the formation of a continuous multi-component tribofilm on the steel counterpart, which reduced direct fabric/steel contact and interfacial shear. This work couples optical release reporting with tribofilm-mediated lubrication, providing a route toward observable self-lubricating fabric composites for enclosed sliding contacts. 

Fabric-reinforced lubricating bearing liners used in aerospace and heavy machinery applications must endure severe wear and high thermal loads. To address these challenges, this study introduces an innovative three-dimensional (3D) fabric liner structure specifically designed for lubricating applications. The liner is composed of aramid fiber (AF) and polytetrafluoroethylene (PTFE), both of which are chosen for their superior mechanical strength and thermal resistance. Compared with their conventional two-dimensional (2D) counterparts, the newly developed 3D AF/PTFE composite exhibited significantly enhanced mechanical performance and a 44% reduction in the wear rate. These improvements are primarily attributed to the excellent structural integrity and heightened interlaminar shear strength of the composite. These findings suggest that 3D AF/PTFE fabrics offer substantial promise as continuous thermal conduction substrates in various applications.

Stimulus-responsive polymers have steadily grown in significance over the past few decades, with extensive research dedicated to the intelligent design of friction materials inspired by natural processes. In this study, we introduce a hydrogel system, CS-MXene@P(AAc-CaAc-co-HEMA-Br)@PSPMA (M-PAAc@PSPMA), that adeptly modulates its modulus across temperature variations, subsequently influencing the interface friction coefficient. The integration of CS-MXene as a photothermal agent facilitates interface temperature modulation under near-infrared (NIR) light irradiation. By manipulating the temperature, the modulus of the P(AAc-CaAc-co-HEMA-Br) hydrogel can be effectively regulated. Moreover, the poly(3-sulfopropyl methacrylate potassium) (PSPMA) polyelectrolyte brush further refines the lubricating attributes of the system. Under ambient conditions, the hydrogel is characterized by a low modulus, heightened flexibility, diminished strength, and a friction coefficient of approximately 0.24. In contrast, under NIR irradiation, the modulus, hardness, and strength of the hydrogel increased, and the friction coefficient decreased to approximately 0.1. This innovative hydrogel system offers advanced friction control by modulating its modulus, setting a precedent for the future development of intelligent lubricant hydrogels, interface detection, and regulated transmission.

In response to the ongoing energy crisis, advancing the field of electrocatalytic water splitting is of utmost significance, necessitating the urgent development of high-performance, cost-effective, and durable hydrogen evolution reaction catalysts. But the generated gas bubble adherence to the electrode surface and sluggish separation contribute to significant energy loss, primarily due to the insufficient exposure of active sites, thus substantially hindering electrochemical performance. Here, we successfully developed a superaerophobic catalytic electrode by loading phosphorus-doped nickel metal (NiP_x) onto various conductive substrates via an electrodeposition method. The electrode exhibits a unique surface structure, characterized by prominent surface fissures, which not only exposes additional active sites but also endows the electrode with superaerophobic properties. The NiP_x/Ti electrode demonstrates superior electrocatalytic activity for hydrogen evolution reaction, significantly outperforming a platinum plate, displaying an overpotential of mere 216 mV to achieve a current density of −500 mA cm⁻² in 1 M KOH. Furthermore, the NiP_x/Ti electrode manifests outstanding durability and robustness during continuous electrolysis, maintaining stability at a current density of −10 mA cm⁻² over a duration of 2000 h. Owing to the straightforward and scalable preparation methods, this highly efficient and stable NiP_x/Ti electrocatalyst offers a novel strategy for the development of industrial water electrolysis.