Silica Nanochannel Array Film Supported by ß-Cyclodextrin-Functionalized Graphene Modified Gold Film Electrode for Sensitive and Direct Electroanalysis of Acetaminophen

Convenient and sensitive detection of active analytes in complex matrix is crucial in biological, medical, and environmental analysis. Silica nanochannel array film (SNF) equipped electrochemical sensors have shown excellent anti-fouling performance in direct analysis of complex samples. In this work, we demonstrated an electrochemical sensor with anti-fouling performance for highly sensitive detection of acetaminophen (APAP) based on SNF supported by ß-cyclodextrin-graphene (CDG) nanocomposite modified Au film electrode (AuF). Because of their rich surface hydroxyls and 2D lamellar structure, CDG on AuF can serve as the nanoadhesive for compact binding SNF, which can be grown by electrochemical assisted self-assembly method in a few seconds. Attributable to the electrocatalytic property of graphene and the synergistic enrichment from both CD and SNF nanochannels towards analyte, the SNF/CDG/AuF sensor demonstrates sensitive detection of acetaminophen ranged from 0.2 to 50 μM with an ultralow limit-of-detection of 14 nM. Taking advantage of the anti-fouling ability of SNF, the sensor is able to realize accurate and convenient analysis of APAP in commercially available paracetamol tablets.

Direct Electrodeposition of Carbon Dots Modifying Bismuth Film Electrode for Sensitive Detection of Cd2+ and Pb2+

A sensitive, selective, and stable sensor for the simultaneous determination of Cd2+ and Pb2+ in aqueous solution has been developed based on the carbon dots (CDs) and Nafion-modified bismuth film glassy carbon electrode (GCE). High graphitized CDs prepared by the sulfuric acid-assisted hydrothermal synthesis were directly electrodeposited on the GCE surface by cyclic voltammetry. Compared with the conventional bismuth film electrodes, CDs greatly improved the electrochemical activity of the bismuth film electrode for the detection of Cd2+ and Pb2+. After decorating CDs, the surface impedance of the GCE was decreased from 10.9 kΩ to 4.84 kΩ. Meanwhile, the corresponding response currents of the Bi/GCE were increased over 7.4 and 2.4 times for Cd2+ and Pb2+ with a wide linear range of 0.05-0.50 mg/L, respectively. High sensitivity was obtained with the detection limits of 3.1 μg L-1 (Cd2+) and 2.3 μg L-1 (Pb2+). Moreover, good stability was obtained for the simultaneous determination of Cd2+ and Pb2+ in the practical underground water with the relative standard deviations less than 10%. The results indicated that the CDs-modified bismuth film electrode could potentially be applied to detect the heavy metal ion concentrations in practical environment.

Photo-Assisted Electrochemical CO2 Reduction Using a Translucent Thin Film Electrode

Herein, we introduce a new concept of photo-assisted electrochemical CO2 reduction through a translucent thin film electrode. Light-compatible thin film electrode directly exposes Au nanoparticles loaded Ag nanowires to gaseous...

The Stable 3D Zn Electrode for High-Power Density Zn Metal Batteries

A stable Zn metal electrode can develop rechargeable zinc metal batteries (RZMBs) which have the high theoretical capacity (820 mAh/g), low redox potential, and intrinsic safety. However, the corrosion of Zn metal in aqueous electrolytes and Zn dendrite formation during the plating process leads to poor cycling and thus hinders the development of RZMBs. Here, we employed ionic liquid-based gel polymer (poly(vinylidene fluoride)-co-hexafluoropropylene, PVDF-HFP) and acetylene black (AB) to achieve a stable and flexible three-dimensional (3D) Zn/AB/PVDF-HFP film electrode with ionic and electronic conductive networks and high surface area, showing 26 times higher plating/stripping current than planar Zn plate. By developing a continuous structure between the ionic liquid-based gel polymer membrane and the flexible 3D Zn/AB/PVDF-HFP electrode, the low resistance, high rate capability and long cycle life (> 800 h) was obtained. Our work shows a flexible Zn film electrode and ionic liquid-based gel polymer electrolyte, could pave the path for rechargeable and high-cycle life thin-film RZMBs.