Fig. 2From: Porous Carbon Substrate Improving the Sensing Performance of Copper Nanoparticles Toward Glucosea, b The scanning electron microscope (SEM) images of Cu NP@PC at different magnifications; c, d The scanning electron microscope (SEM) images of Cu NP/C at different magnifications; e The transmission electron microscopy (TEM) image of Cu NP@PC; and f Brunauer–Emmett–Teller (BET) surface area analysis of Cu NP@PC and Cu NP/CBack to article page