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Energy storage devices with liquid‐metal electrodes have attracted interest in recent years due to their potential for mechanical resilience, self‐healing, dendrite‐free operation, and fast reaction kinetics. Gallium alloys like Eutectic Gallium Indium (EGaIn) are appealing due to their low melting point and high theoretical specific capacity. However, EGaIn electrodes are unstable in highly alkaline electrolytes due to Gallium oxide dissolution. In this letter, this bottleneck is addressed by introducing chemically stable films in which nanoscale droplets of EGaIn are coated with trace amounts of graphene oxide (GO). It is demonstrated that a GO to EGaIn weight ratio as low as 0.01 provides enough protection for a thin film formed by GO@EGaIn nanocomposite against significantly acidic or alkaline environments (pH 1‐14). It is shown that GO coating significantly enhances the surface stability in such environments, thus improving the energy storage capacity by over 10x. Microstructural analysis confirms GO@EGaIn composite stability and enhanced electrochemical performance. Utilizing this, a thin‐film supercapacitor is fabricated. Results indicate that when coating the EGaIn with GO to EGaIn ratio of 0.001, the areal capacitance improves by 10 times, reaching 20.02 mF cm−2. This breakthrough paves the way for advanced liquid metal‐based thin‐film electrodes, promising significant improvements in energy storage applications. [ABSTRACT FROM AUTHOR]

Today, remarkable growth in the generation and abuse of drugs lead to the need for fast, simple, selective, and sensitive methods for their detection. Tramadol is one of the most abused drugs that can make addiction. A highly conductive and highly sensitive voltammetric method is developed for the determination of tramadol based on a 1-methyl-3-butyl imidazolium bromide/praseodymium hydroxide-graphene quantum dots nanocomposite modified carbon paste electrode (1-M-3-BBr/Pr(OH)3-GQD/CPE). According to the obtained voltammograms, the 1-M-3-BBr/Pr(OH)3-GQD/CPE exhibits high catalytic activity on the oxidation signal of tramadol. Tramadol shows an irreversible anodic oxidation peak in the potentials of ~1170 mV and ~1230 mV at the surface of a modified and unmodified CPE, respectively. Square wave voltammogram signals confirmed that the oxidation current of tramadol was increased linearly with its concentration in the range of 9.0×10-9-3.0×10-4 mol L-1 with a detection limit of 3.0×10-9 mol L-1. Finally, the 1-M-3-BBr/Pr(OH)3-GQD/CPE was effectively used for the determination of tramadol in some real samples with an acceptable selectivity. [ABSTRACT FROM AUTHOR]

Analysis of food, pharmaceutical, and environmental compounds is an inevitable issue to evaluate quality of the compounds used in human life. Quality of drinking water, food products, and pharmaceutical compounds is directly associated with human health. Presence of forbidden additives in food products, toxic compounds in water samples and drugs with low quality lead to important problems for human health. Therefore, attention to analytical strategy for investigation of quality of food, pharmaceutical, and environmental compounds and monitoring presence of forbidden compounds in materials used by humans has increased in recent years. Analytical methods help to identify and quantify both permissible and unauthorized compounds present in the materials used in human daily life. Among analytical methods, electrochemical methods have been shown to have more advantages compared to other analytical methods due to their portability and low cost. Most of big companies have applied this type of analytical methods because of their fast and selective analysis. Due to simple operation and high diversity of electroanalytical sensors, these types of sensors are expected to be the future generation of analytical systems. Therefore, many scientists and researchers have focused on designing and fabrication of electroanalytical sensors with good selectivity and high sensitivity for different types of compounds such as drugs, food, and environmental pollutants. In this paper, we described the mechanism and different examples of DNA, enzymatic and electro‐catalytic methods for electroanalytical determination of drug, food and environmental compounds. [ABSTRACT FROM AUTHOR]