To improve the thermophysical properties of Al alloy for thermal management materials, the Cu-coated carbon fibers (CFs) were used as reinforcement to improve the thermal conductivity (TC) and the coefficient of thermal expansion (CTE) of Al-12Si. The CFs reinforced Al matrix (CFs/Al) composites with different CFs contents were prepared by stir casting. The effects of the CFs volume fraction and Cu coating on the microstructure, component, TC and CTE of CFs/Al composites were investigated by scanning electron microscopy with EDS, X-ray diffraction, thermal dilatometer and thermal dilatometer. The results show that the Cu coating can effectively improve the interface between CFs and the Al-12Si matrix, and the Cu coating becomes Al2Cu with Al matrix after stir casting. The CFs/Al composites have a relative density greater than 95% when the volume fraction of CFs is less than 8% because the CFs uniform dispersion without agglomeration in the matrix can be achieved by stir casting. The TC and CTE of CFs/Al composites are further improved with the increased CFs volume fraction, respectively. When the volume fraction of CFs is 8%, the CFs/Al composite has the best thermophysical properties; the TC is 169.25 W/mK, and the CTE is 15.28 × 10– 6/K. The excellent thermophysical properties of CFs and good interface bonding are the main reasons for improving the thermophysical properties of composites. The research is expected to improve the application of Al matrix composites in heat dissipation neighborhoods and provide certain theoretical foundations.

A promising approach to enhance catalytic performance of supported heterogeneous nano-metal catalysts is to uniformly disperse active nanoparticles on the support. In this work, N-doped carbon-modified graphene (G@NC) nanosheet is designed and prepared to anchor Pd–Fe bimetallic nanoparticles (Pd–Fe/G@NC). The N-doped carbon modification on graphene surface could construct a sandwich-like structure (G@NC), which not only prevented the re-stacking of graphene nanosheets but also provided confined space for stable anchoring of bimetallic Pd–Fe nanoparticles. Benefitted from the unique structural property and synergetic effect of metal Pd and Fe species, the as-obtained Pd–Fe/G@NC composite displays excellent catalytic activity toward 4-nitrophenol reduction reaction with a turnover frequency of 613.2 min− 1, which is far superior to that of the mono-metal counterparts (Fe/G@NC and Pd/G@NC). More importantly, Pd–Fe/G@NC catalyst also exhibits favorable catalytic performance in the reduction of other nitroaromatic compounds (nitrobenzene, 4-nitrotoluene, 4-chloronitrobenzene, and so on). In addition, Pd–Fe/G@NC can catalyze the oxidation of furfuraldehyde to furoic acid with a high yield of 88.64%. This work provides a new guide for rationally designing and developing advanced supported heterogeneous bimetallic catalyst.