Multifunctional, wearable, and durable textiles integrated with smart electronics have attracted tremendous attention. However, it remains a great challenge to balance new functionalities with high temperature stability. Herein, textile-based pressure-sensors with excellent electromagnetic interference (EMI) shielding, Joule heating and high temperature resistance were fabricated by constructing graphene/SiC (G/SiC) heterostructures on carbon cloth via laser chemical vapor deposition (LCVD). The resultant textile exhibited excellent EMI efficiency of 74.2 dB with a thickness of 0.45 mm, Joule heating performance within low working voltage range of 1 to 3 V and fast response time within 20 s. These properties arose from multiple reflections, interfacial polarizations and high conductivity due to the numerous amounts of nanoscale G/SiC heterostructures. More importantly, the G/SiC/CFs demonstrated well high temperature resistance with a THRI of 380.16 oC owing to the protection of the coating layer on the carbon fibers upon oxidation. Meanwhile, the G/SiC/CFs presented good pressure-sensing performance with a high sensitivity of 52.93 kPa−1, fast response time of 85 ms and wide pressure range up to 186 kPa. These features imply the potential of G/SiC/CFs as an efficient EMI shielding, electrical heater and piezoresistive sensor textiles.
As a typical process-intensive strategy, a tandem reaction driven by a multifunctional catalyst is a paragon of the green catalytic process. Two or more active sites are usually required and their rational spatial distribution is critical for the multi-functional catalyst to act independently or synergistically. Here, we present a simple and stepwise method to construct a trifunctional integrated catalyst simultaneously with spatially intimate acidic (phosphotungstic acid (HPW)), basic (amino) and metal (Pd nanoparticles (NPs)) sites in hierarchically porous UiO-66-NH2. Through fine controlling the ratio of immobilized HPW and amino groups, we can easily tune its accessible acidic and basic properties, and the anchored HPW molecules can be effectively used to mediate the catalytic performance of Pd NPs and further stabilize the Pd sites. This well-designed integrated catalyst showed excellent catalytic activity and yield (>97%) towards one-pot three-step Deacetalization–Knoevenagel–Hydrogenation (D–K–H) catalysis reactions owing to the synergetic catalysis and the intimate spatial arrangement of the acid, basic and metal sites. More importantly, the trifunctional catalyst could be recycled at least five times without significantly losing its activity due to the strong interaction between the MOF and the guest molecules. This work provides some important insights into the construction of multifunctional integrated catalysts, especially for the application in challenging tandem catalysis.