Copper nanoparticles suitable for bifunctional cholesterol oxidation reaction: harvesting energy and sensor

Abstract

This study reports the performance of simple low-cost synthesized bifunctional Cu/Cu2O nanoparticles (NPs) used as a catalyst for energy-harvesting applications through of a microfluidic fuel cell (µFC), and further, as cholesterol (Chol) sensor. TEM characterization of the NPs showed spheres between 4 and 10 nm, while XRD and XPS analysis confirmed the composition and preferential crystallographic plane of Cu/Cu2O. In addition, 25.26 m2 g−1 surface area was obtained, which is greater than those commercial materials. NPs showed high activity toward the cholesterol oxidation reaction when were used as a sensor, obtaining a linear interval between 0.5 and 1 mM and 850 µA mM−1 mg−1 of sensitivity and 8.9 µM limit of quantification LOQ. These values are comparable to results previously reported. Moreover, Cu/Cu2O NPs were used as anode in a µFC with 0.96 V of cell voltage and 6.5 mA cm−2 and 1.03 mW cm−2 of current and power density, respectively. This performance is the highest currently reported for cholesterol application as an alternative fuel, and the first one reported for a microfluidic fuel cell system as far as is known. Results showed that the obtained Cu-based NPs presented an excellent performance for the dual application both µFC and sensor, which has potential applications in biomedicine and as an alternative energy source.

NiCo2O4@SnS2 nanosheets on carbon cloth as efficient bi-functional material for high performance supercapacitor and sensor applications

“…To resolve the global energy crises and pharmaceutical issues, development of an efficient electrode materials having bifunctional capabilities especially for the detection of L-Cysteine as well as supercapacitor applications, is urgently required. In this perspective, until now various metal oxides based bi-functional materials are being employed for energy as well as sensing applications [6][7][8][9][10][11]. However, these electrode materials are facing serious problems of low energy and cyclic instability in supercapacitors and poor sensitivity for sensor which hinder their practical utilization.…”