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A nonenzymatic electrochemical method using PtRu-modified screen-printed edge band ultramicroelectrode has been developed for selective and sensitive detection of glycerol. It was based on the periodate oxidation of glycerol and the as-formed formic acid and formaldehyde was detected by the proposed electrochemical sensor in the gas phase. This approach simplified the two steps of sample preparation and detection into a 2-in-1 single step process. It also eliminated almost all of the interferants in the solution phase and hence resulted in a highly selective analysis of glycerol. The proposed approach improved the analytical performance of other electroanalytical methods for quantification of glycerol with a low detection limit of 0.51 mg L −1 glycerol (S/N = 3) and a wide linear range of 0.92–92 mg L −1 . Especially, for monitoring free glycerol in biodiesel, no extraction of glycerol from biodiesel to eliminate organic interferents was required. The accuracy was evaluated using a spike-and-recovery assay to prove its applicability as a valuable tool for practical glycerol analysis.

We report here the preparation and mechanistic explanation of a nitrogen rich platform, poly(melamine), and its application for efficient synthesis of carbon nanotube–metal nanoparticle hybrid. Poly(melamine) is electrochemically formed on the surface of a preanodized screen-printed carbon electrode (designated as SPCE*) under a suitable potential (1.5 V vs. Ag/AgCl) and pH (0.1 M HCl). Note that radical cation formation is the rate-determining step in melamine polymerization and an enough positive potential in highly acidic medium is essential for the formation and stabilization of radical cation. The XPS analysis indicates the generation of polymer by head-to-head coupling with NH NH bonding between melamine molecules. We demonstrate that this poly(melamine)-modified electrode is helpful in loading copper nanoparticles on multiwalled carbon nanotube for hybrid formation. Since the proposed method is easy for mass production, this report opens a new methodology to functionalize the carbon surface to prepare new materials in different fields.

Herein we report an effective method to enhance microbial immobilization on screen-printed carbon electrode (SPCE) surface by electrochemical regulation of redox potential. This technique could deliver a prospective electrode for microbial biofuel cell and other applications. A phototrophic purple nonsulfur bacterium Rhodopseudomonas palustris CGA009 was selected as a model organism to examine the proposed approach. Scanning the electrode between −0.7 to 0.3 V (vs. Ag/AgCl) at 70 mV/s for 50 cycles (∼24 min), placed in the growth medium with bacteria, significantly increased microbial adhesion when compared to SPCE without electrochemical stimulation. The electron-transfer effect between the adsorbed microorganism and electrode surface was further studied by AC impedance spectroscopy to confirm the accelerated microbial immobilization. Stable photosynthetic electron transport chain from immobilized bacteria through SPCE was achieved.

In this study, we report the application of an inexpensive and easily prepared lead oxide–manganese oxide catalyst combined with Nafion (designated as Nf/PbMnO x ) as a highly efficient air-cathode for a zinc–air battery. We verify the mechanistic study of the reduction of O 2 for Nf/PbMnO x in alkaline aqueous solution using rotating ring/disk electrode voltammetry, and also an electrochemical approach using a wall-jet screen-printed ring disk electrode. The presence of Nf/PbMnO x shows great catalytic activity for the disproportionation reaction of HO 2 − to O 2 and OH − with an overall 4e − reduction of O 2 in the first reduction reaction. The 4e − reduction of O 2 was eventually achieved at the Nf/PbMnO x through evidence from the slope of Koutecky–Levich plots. With these inherent features, we then fabricated the zinc–air battery with the Nf/PbMnO x catalyst and examine the performance for a practical application with air cathodes.

We report here preparation and characterization of an AuCu 3 alloy electrochemical sensing platform fabricated on an easy for mass production barrel-plated gold electrode (AuBPE). Note that the AuBPE consists of Cu main body with successive plating of a very thin layer of Ni and Au (i.e., Cu–Ni–Au multilayer). By suitably manipulating the grain boundary diffusion between individual metallic layers of Cu–Ni–Au by means of thermal annealing treatment, AuCu 3 alloy film can be formed directly on the outer surface of the AuBPE. Electrochemical activation in alkaline solution can further generate a nanostructured AuCu 3 alloy film. This facile and novel approach is promising to prepare sensors for electroanalytical applications, e.g., glucose oxidation in pH-neutral solutions and simultaneous detection of uric acid, dopamine and ascorbic acid.