Facile Synthesis of Palladium-Nanoparticle-Embedded N-Doped Carbon Fibers for Electrochemical Sensing

2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. In recent years, there have been many studies on metal/carbon hybrid materials for electrochemical applications. However, reducing the metal content in catalysts is still a challenge. Here, a facile synthesis of palladium (Pd) nanoparticle-embedded N-doped carbon fibers (Pd/N-C) through electropolymerization and reduction methods is demonstrated. The as-prepared Pd/N-C contains only 1.5wt% Pd. Under optimal conditions, bisphenolA is detected by using amperometry in two dynamic ranges from 0.1 to 10μm and from 10 to 200μm, and the obtained correlation coefficients are close to 0.9836 and 0.9987, respectively. The detection limit (DL) for bisphenolA is determined to be 29.44 (±0.77)nm

Facile Synthesis of Palladium-Nanoparticle-Embedded N-Doped Carbon Fibers for Electrochemical Sensing

2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. In recent years, there have been many studies on metal/carbon hybrid materials for electrochemical applications. However, reducing the metal content in catalysts is still a challenge. Here, a facile synthesis of palladium (Pd) nanoparticle-embedded N-doped carbon fibers (Pd/N-C) through electropolymerization and reduction methods is demonstrated. The as-prepared Pd/N-C contains only 1.5wt% Pd. Under optimal conditions, bisphenolA is detected by using amperometry in two dynamic ranges from 0.1 to 10μm and from 10 to 200μm, and the obtained correlation coefficients are close to 0.9836 and 0.9987, respectively. The detection limit (DL) for bisphenolA is determined to be 29.44 (±0.77)nm

Facile Synthesis of Palladium-Nanoparticle-Embedded N-Doped Carbon Fibers for Electrochemical Sensing

2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. In recent years, there have been many studies on metal/carbon hybrid materials for electrochemical applications. However, reducing the metal content in catalysts is still a challenge. Here, a facile synthesis of palladium (Pd) nanoparticle-embedded N-doped carbon fibers (Pd/N-C) through electropolymerization and reduction methods is demonstrated. The as-prepared Pd/N-C contains only 1.5wt% Pd. Under optimal conditions, bisphenolA is detected by using amperometry in two dynamic ranges from 0.1 to 10μm and from 10 to 200μm, and the obtained correlation coefficients are close to 0.9836 and 0.9987, respectively. The detection limit (DL) for bisphenolA is determined to be 29.44 (±0.77)nm

Design and Development of Noble Metal Based Porous Materials as Electrocatalysts

Electrocatalysts are in the spotlight due to their various applications, including energy storage and sensors. Among them, electrocatalysts used as sensor electrodes are very important because they are relevant to human health. Many studies have been made to increase the efficiency of the electrocatalysts via the development of new catalytic materials. Among the various materials, noble metal-based materials are considered important because of their good catalytic properties, although they have the disadvantage that they are expensive compared to common materials. Therefore, various methods, such as changing their morphology, increasing their surface area, and size control, have been employed to overcome this drawback. This thesis introduces the synthesis of noble-metal-based electrode materials and their applications. Dendritic platinum nanoparticles (DPNs) have been synthesized using an amphiphilic non-ionic surfactant (Brij 58® ) via a sonochemical method. The particle size of the DPNs can be tuned by changing the reduction temperature, which resulted in a uniform DPN with a size of 23 nm or 60 nm. The facets of DPNs were observed by high-resolution transmission electron microscopy (TEM). In addition, the cytotoxicity of DPNs was investigated for biosensor applications using human embryonic kidney cells (HEK-293)

Highly active coral-like porous silver for electrochemical reduction of CO2 to CO

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Improved Activity for Oxygen Evolution Reaction of Nanoporous IrNi thin film Achieved by Electrochemical Selective Dealloying

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Improved Activity for Oxygen Evolution Reaction of Nanoporous IrNi thin film Achieved by Electrochemical Selective De-alloying of Os

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Rationally designed bimetallic Au@Pt nanoparticles for glucose oxidation

Bimetallic nanoparticles (NPs) have aroused interest in various fields because of their synergetic and unique properties. Among those nanoparticles, we strategically approached and synthesized Au@Pt NPs via the sonochemical method with different molar ratios (e.g. 3:7, 5:5, and 7:3) of Au to Pt precursors. The particle structure was confirmed to be core-shell, and the size was estimated to be 60, 52, and 47 nm, respectively, for 3:7, 5:5, and 7:3 ratios of Au to Pt. The detailed structure and crystallinity of as-prepared Au@Pt NPs were further studied by scanning electron microscopy, transmission electron microscopy with element mapping, and X-ray diffraction. It should be noted that thickness of the dendritic Pt shell in the core-shell structure can be easily tuned by controlling the molar ratio of Au to Pt. To explore the possibility of this material as glucose sensor, we confirmed the detection of glucose using amperometry. Two dynamic ranges in a calibration plot were displayed at 0.5-50.0 µM and 0.05-10.0 mM, and their detection limit as glucose sensor was determined to be 319.8 (±5.4) nM

Facile Synthesis of Palladium-Nanoparticle-Embedded N-Doped Carbon Fibers for Electrochemical Sensing

2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. In recent years, there have been many studies on metal/carbon hybrid materials for electrochemical applications. However, reducing the metal content in catalysts is still a challenge. Here, a facile synthesis of palladium (Pd) nanoparticle-embedded N-doped carbon fibers (Pd/N-C) through electropolymerization and reduction methods is demonstrated. The as-prepared Pd/N-C contains only 1.5wt% Pd. Under optimal conditions, bisphenolA is detected by using amperometry in two dynamic ranges from 0.1 to 10μm and from 10 to 200μm, and the obtained correlation coefficients are close to 0.9836 and 0.9987, respectively. The detection limit (DL) for bisphenolA is determined to be 29.44 (±0.77)nm

A facile approach for constructing conductive polymer patterns for application in electrochromic devices and flexible microelectrodes

We developed a novel strategy for fabricating poly(3,4-ethylenedioxythiophene) (PEDOT) patterns on various substrates, including hydrogels, via sequential solution procedure without multistep chemical etching or lift-off processes. First, PEDOT nanothin films were prepared on a glass substrate by solution phase monomer casting and oxidative polymerization. As a second step, after UV-induced poly(ethylene glycol) (PEG) photolithography at the PEDOT/PEG interface through a photomask, the hydrogel was peeled away from the PEDOT-coated glass substrate to detach the UV-exposed PEDOT region, which left the UV nonexposed PEDOT region intact on the glass substrate, resulting in PEDOT patterns. In a final step, the PEDOT patterns were cleanly transferred from the glass to a flexible hydrogel substrate by a direct-transfer process based on a second round of gelation process. Using this strategy, PEDOT patterns on ITO glass or ITO film were used to successfully fabricate an electrochromic (EC) device that exhibited stable electrochromic switching as a function of applied potential. Furthermore, PEDOT patterns on hydrogel were used to fabricate all organic, flexible microelectrodes with good electrical properties and excellent mechanical flexibility. Importantly, the conductivity of PEDOT patterns on hydrogel (ca. 235 S cm-1) described here is significantly higher than that previously reported (ca. 20-70 S cm-1). This approach can be easily integrated into various technological fabrication steps for the development of next-generation bioelectronics systems