Simultaneous Analysis of Hydroquinone, Arbutin, and Ascorbyl Glucoside Using a Nanocomposite of Ag@AgCl Nanoparticles, Ag2S Nanoparticles, Multiwall Carbon Nanotubes, and Chitosan

A nanocomposite comprising Ag nanoparticles on AgCl/Ag2S nanoparticles was decorated on multi-walled carbon nanotubes and used to modify a glassy carbon electrode. Chitosan was also formulated in the nanocomposite to stabilize Ag2S nanoparticles and interact strongly with the glucose moiety of arbutin (AR) and ascorbyl glucoside (AA2G), two important ingredients in whitening lotion products. The modified electrode was characterized by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and scanning electron microscopy (SEM) and cyclic voltammetry and used for the simultaneous analysis of hydroquinone (HQ), AR, and AA2G. The electrode showed excellent electrocatalysis towards the analytes by shifting the anodic peak potential to a negative direction with ≈5-fold higher current. The sensor displayed a linearity of 0.91-27.2 μM for HQ, 0.73-14.7 μM for AR, and 1.18-11.8 μM for AA2G, without cross-interference. A detection limit was 0.4 μM for HQ, 0.1 μM for AR, and 0.25 μM for AA2G. The sensor was applied to determine HQ, AR, and AA2G spiked in the whitening lotion sample with excellent recovery. The measured concentration of each analyte was comparable to that of the high performance liquid chromatographic (HPLC) method.

Atomic-level design of CoOH+–hydroxyapatite@C catalysts for superfast degradation of organics via peroxymonosulfate activation

In situ formation of CoOH⁺–hydroxyapatite@C via ion exchange between Ca and Co realises the simultaneous adsorption of Co²⁺ and catalytic peroxymonosulfate oxidation for superfast oxidative degradation of organic contaminants.

Simple and scalable growth of AgCl nanorods by plasma-assisted strain relaxation on flexible polymer substrates

Implementing nanostructures on plastic film is indispensable for highly efficient flexible optoelectronic devices. However, due to the thermal and chemical fragility of plastic, nanostructuring approaches are limited to indirect transfer with low throughput. Here, we fabricate single-crystal AgCl nanorods by using a Cl₂ plasma on Ag-coated polyimide. Cl radicals react with Ag to form AgCl nanorods. The AgCl is subjected to compressive strain at its interface with the Ag film because of the larger lattice constant of AgCl compared to Ag. To minimize strain energy, the AgCl nanorods grow in the [200] direction. The epitaxial relationship between AgCl (200) and Ag (111) induces a strain, which leads to a strain gradient at the periphery of AgCl nanorods. The gradient causes a strain-induced diffusion of Ag atoms to accelerate the nanorod growth. Nanorods grown for 45 s exhibit superior haze up to 100% and luminance of optical device increased by up to 33%.

Singlet oxygen formation in bio-inspired synthesis of a hollow Ag@AgBr photocatalyst for microbial and chemical decontamination

Singlet oxygen has been identified as a contributor to the degradation of contaminants using biosynthesised hollow Ag@AgBr catalysts.

Controlling the morphology and composition of Ag/AgBr hybrid nanostructures and enhancing their visible light induced photocatalytic properties

Ag/AgBr hybrid nanostructures were prepared by reducing AgBr nanoparticles synthesized by reaction of Ag⁺ with Br⁻. The Ag/AgBr hybrid nanostructures exhibited enhanced photocatalytic activity and recyclability for decomposing methylene blue (MB).