Facile wet-chemical synthesis of differently shaped cuprous oxide particles and a thin film: Effect of catalyst morphology on the glucose sensing performance

Abstract

In this work, different facile synthesis routes were developed to create cuprite-based catalyst systems for the amperometric detection of glucose, allowing us to evaluate the impact of important electrode fabrication parameters on the glucose sensing performance. Using homogenous precipitation routes based on a redox system, two differently shaped cuprite particles-skeletons and polyhedrons-could be obtained. Furthermore, a novel electroless deposition technique was introduced that does not require sensitization and activation pretreatments, allowing for the direct modification of the glassy carbon. This technique produced electrodes with dense thin film consisting of merged, octahedral cuprite crystals. Afterward, these materials were tested as potential catalysts for the electrochemical detection of glucose. While the catalyst powders obtained by precipitation required Nafion ® to be attached to the electrode, the thin film synthesized using electroless plating could be realized with and without additive. Summarizing the results, it was found that Nafion ® was not required to achieve glucose selectivities typically observed for cuprite catalysts. Also, the type of catalyst application (direct plating versus ink drop coating) and the particle shape had a pronounced effect on the sensing performance. Compared to the thin film, the powder-type materials showed significantly increased electrochemical responses. The best overall performance was achieved with the polyhedral cuprite particles, resulting in a high sensitivity of 301 µA . mmol -1 cm -2 , a linear range up to 298 µmol . L -1 and a limit of detection of 0.144 µmol . L -1 .2

Electroless Metallization of the Elements: Survey and Progress

“…Changes in the oxidation state of materials in contact with redox active surfaces or solution species have also been described for the EL deposition of oxides of Ti, V, , Mo, , W, ,, Mn, ,,, Fe, ,,,, Ru, ,,, Ir, Cu, , Pb, and mixed metals. ,,, For example, Moulai and co-workers report the deposition of MnO 2 onto H-terminated Si nanowires via simple treatment of the Si nanowires with aqueous KMnO 4 solution. Galvanic reduction of MnO 4 – by the Si–H surface species, which are oxidized, deposits MnO 2 NPs onto the Si nanowires to create a MnO 2 −Si nanowire composite.…”

“…Changes in the oxidation state of materials in contact with redox active surfaces or solution species have also been described for the EL deposition of oxides of Ti, 148 V, 148,187 Mo, 145,148 W, 108,145,147 Mn, 149,150,188,189 Fe, 2,155,156,158,188 Ru, 110,162,163,188 Ir, 166 Cu, 90,167 Pb, 173 and mixed met- als. 88,143,157,169 For example, Moulai and co-workers 189 report the deposition of MnO 2 onto H-terminated Si nanowires via simple treatment of the Si nanowires with aqueous KMnO 4 solution.…”

“…EL Cu has also been used with success for the fabrication of sensor electrodes. The work of Neetzel et al concerning cuprite electrodes as glucose sensors has already been described in this section in connection with the discussion of EL deposition of copper oxides ( vide supra ). Glucose sensors have also been described using Cu films as electrodes. , For example, Thota and Ghosh report fabrication of a flexible and disposable nonenzymatic glucose sensor based on EL Cu deposition onto oxidized transparent PE films modified with APTES SAM film and PANI (leucoemeraldine base form).…”

“…These researchers deposit a ∼100 nm thick sacrificial chitosan layer onto a glass substrate as large as 20 cm × 30 cm via ultrasonic atomization of a solution of 95% deacetylated chitosan in HOAc/ethanol. Soaking the film in a 167 concerning cuprite electrodes as glucose sensors has already been described in this section in connection with the discussion of EL deposition of copper oxides (vide supra). Glucose sensors have also been described using Cu films as electrodes.…”

One-step melamine-assisted synthesis of graphene-supported AuPt@Au nanocrystals for enhanced catalytic reduction of p-nitrophenol

“…18 Among them, wet chemical reduction possesses the merits of low cost, simplicity and feasibility, and thereby many nanostructures were prepared by reducing the metal salt precursors from aqueous phase. 19,20 Graphene attracts tremendous interest in material, chemistry and physics because of its enlarged theoretical surface area, high electrical conductivity, good thermal/chemical stability and strong mechanical strength. [21][22][23] As a result, graphene is widely explored in sensors, 24 hydrogen storage devices, 25 transistors 26 and catalysis.…”