Preparation Of Copper-based Nanoporous Composite And Their Electrocatalytic Performance For Glucose

In this work,the Cu_xO@NPC(x=1,2)and Cu_xO/Ag₂O@NP-CuAg(x=1,2)nanowire composite electrodes have been successfully prepared by dealloying Cu_50-xZr₅₀Ag_x(x=0,7.5at.%)amorphous alloys,followed by anodizing and calcination.The effect of anodizing time on the micro-morphology of nanowire composites was studied.The glucose electrocatalytic performance of the two types of electrodes was detected.Meanwhile,the effects of the addition of Ag element on the microstructure and electrocatalytic properties of the materials were systematically discussed.In addition,the glucose electrocatalytic reaction mechanism of the copper-silver bimetallic electrode was analyzed.Two types of free-standing Cu_xO@NPC and Cu_xO/Ag₂O@NP-CuAg composite electrodes with Cu_xO or Cu_xO/Ag₂O nanowires in-situ grown on the ligament/pore bi continuous nanoporous substrate were successfully prepared via dealloying Cu₅₀Zr₅₀ and Cu_42.5Zr₅₀Ag_7.5 amorphous ribbons in 0.05 M HF solution,followed by anodizing and calcining.These research results are shown as follows:(1)The nanowires of the composite electrodes have different morphological characteristics,that is,Cu_xO nanowires with a cluster structure,while Cu_xO/Ag₂O nanowires exhibit the feature of top aggregation;(2)The evolution of nanowires is related to the anodizing time.With the increase of the anodizing time,the length of the nanowires increases.Moreover,the nanowires become denser from sparse;(3)Two types of composite electrodes have the hierarchical porous structure,which is composed of nanopores on porous substrate,micropores between staggered nanowires and the small pores on the nanowires;(4)The as-prepared bimetallic Cu-Ag composite electrode shows good flexibility.On the other hand,the glucose electrocatalytic performance of Cu_xO@NPC and Cu_xO/Ag₂O@NP-CuAg composite electrodes were detected.As a result,the existence of Cu_xO and Cu_xO/Ag₂O nanowires is beneficial to improve the electrocatalytic performance of composites.Moreover,compared with single metal Cu_xO@NPC composite electrodes,the bimetallic Cu_xO/Ag₂O@NP-CuAg composite electrodes exihibit better glucose electrocatalytic performance.In addition,the electrode anodized for 10 min(Cu_xO/Ag₂O-10)has the high sensitivity of 1.49 m A cm^-2 m M^-1,the wide linear range reaching up to 17 m M,and the low detection concentration of 200 n M.Its sensitivity and linear range are significantly better than that of Cu_xO@NPC(0.9 m A cm^-2 m M^-1;15 m M)and reported Ag/Cu O NFs(1.35 m A cm^-2 m M^-1;0.5 m M),which is due to the synergistic effect of the hierarchical porous structure and the dual metal element.The interconnected hierarchical porous structure not only facilitates electron and ion transport,but also provides abundant reaction contact sites.In addition,the synergistic effect of the multi-component and multi-valent of the Cu-Ag bimetallic composite electrode is beneficial to improve electrocatalytic performance of electrode.Therefore,the as-prepared flexibility self-supporting Cu_xO/Ag₂O-10 composite material with excellent electrocatalytic performance for glucose is expected to be further developed as a candidate electrode material for glucose sensors.