The application of Au nanoparticles (Au NPs) often requires surface modification with chemical surfactants, which dramatically reduce the surface activity and increase the chemical contamination and cost of Au NPs. In this research, we have developed a novel Au NPs/reduced graphene oxide/Ni foam hybrid (Au NPs/RGO/NiF) by in situ reduction through ascorbic acid and replacement reaction. This method is green, facile and efficient. The Au NPs are free of chemical surfactants and are homogeneously distributed on the surface of the RGO/NiF. The as-prepared Au NPs/RGO/NiF hybrid is uniform, stable and exhibits not only a high reduction efficiency for the reduction of 4-nitrophenol with a catalytic kinetic constant of up to 0.46 min (0.15 cm catalysis) but also a sensitive and selective detection of HO with a detection limit of ∼1.60 μM.

The weak signal from rare event is readily submerged in the background and thus results in substantial challenges in its detection, which spurs researchers to decrease the surroundings background of detectors as low as possible. To this end, a low-background non-adhesive polytetrafluoroethylene (PTFE) flexible copper-clad laminate (PTFE-FCCL) was prepared by surface treatment. Specifically, the PTFE substrate was processed by ion implantation and the transition layer deposition; the adhesion between PTFE and copper of PTFE-FCCL is found to remain stable after barely immersing in liquid nitrogen. Furthermore, the surface morphology and the dielectric properties of the substrate were characterized and tested. The results presented herein offer a novel method to fabricate electronic substrates that can facilitate rare event detection.