Design of Double-Shelled CuS Nanocages to Optimize Electrocatalytic Dynamic for Sensitive Detection of Ascorbic Acid

Abstract

Although transition metal sulfides have presented prospect in electrochemical sensing, their electrocatalytic performance still cannot meet the demands for practical applications due to the difficulties in mass transport and electron transfer. In this work, double-shelled CuS nanocages (2-CuS NCs) were prepared for enzyme-free ascorbic (AA) sensor through a Cu 2 O-templated method. The unique double-shelled hollow structure displayed large specific surface areas, ordered diffusion channels, increased volume occupying rate, and accelerated electron transfer rate, resulting in enhanced electrochemical dynamic. As a sensing electrode for AA, 2-CuS NCs modified glassy carbon electrode (2-CuS NCs/GCE) exhibited eminent electrocatalytic activity in terms of satisfying sensitivity (523.7 μA mM −1 cm −2 ), short response time (0.31 s), and low limit of detection (LOD, 0.15 μM). 2-CuS NCs look promising for analytical sensing of AA in electrochemical sensors thanks to its prominent electrocatalytic kinetics issued from double-shelled hollow porous structure.

Sodium Alginate–CuS Nanostructures Synthesized at the Gel–Liquid Interface: An Efficient Photocatalyst for Redox Reaction and Water Remediation

“…Similar to Cu, the S­(2p) was deconvoluted into S 2– (2p 3/2 ) and S 2– (2p 1/2 ) at binding energies of 161.29 eV and 162.45 eV, respectively, as shown in Figure b. However, the characteristic peak observed at the BE of 168.10 eV indicates metal sulfide formation. , These results confirm the formation of pristine CuS at the gel–liquid interface. The deconvoluted C­(1s) spectrum (Figure c) shows four distinct peaks at BE values of 284.58, 286.17, 287.89, and 288.60 eV, which are assigned to the existence of C–H or C–C, C–O, O–C–H, and COOH, respectively. , Interestingly, the O­(1s) spectrum was deconvoluted into two peaks at the BE of 530.81 and 532.34 eV corresponding to the core levels of O 2– ions and surface contamination, as shown in Figure d .…”