Silver-functionalized bismuth oxide (AgBi2O3) nanoparticles for the superior electrochemical detection of glucose, NO2- and H2O2

Reducing noble metal dependence: oxygen evolution reaction with a Ru-minimized Bi2Ru2O7@MOF-801 composite

Developing efficient and noble metal-minimized electrocatalysts for the oxygen evolution reactions (OER) is critical for energy conversion reactions. Here we present Ru-minimized Bi2Ru2O7@MOF-801 that synergistically combines the high catalytic activity of the bimetallic oxide with the unique structural and hydrophilic properties of the Zr-MOF. The composite achieves superior OER performance with a low overpotential of 307 mV at 50 mA cm-2 and a Tafel slope of 99.8 mV dec-1 surpassing those of pure Bi2Ru2O7 and MOF-801. Comparative testing with cutting-edge catalysts shows that using less Ru and incorporating a MOF work well together, providing a promising way to make high-performance OER catalysts that are also cost-effective by integrating the MOF for energy applications.

Synthesis of silver‑bismuth oxide encapsulated hydrazone functionalized chitosan (AgBi2O3/FCS) nanocomposite for electrochemical sensing of glucose, H2O2 and Escherichia coli O157:H7

In this work, silver‑bismuth oxide encapsulated 1,3,5-triazine-bis(4-methylbenzenesulfonyl)-hydrazone functionalized chitosan (SBO/FCS) nanocomposite was synthesized by a simple hydrothermal method. The amine (-NH2) group was functionalized by the addition of cyanuric acid chloride followed by 4-methylbenzenesulfonol hydrazide. The SBO/FCS has been characterized by FT-IR, X-ray diffraction, XPS, HR-SEM, HR-TEM, AFM, and thermogravimetry (TGA). Under the optimum conditions, the SBO/FCS sensor showed brilliant electrochemical accomplishment for the sensing of glucose and H2O2 by a limit of detection (LOD) of 0.057 μM and 0.006 μM. It also showed linearity for glucose 0.008-4.848 mM and for H2O2 of 0.01-6.848 mM. Similarly, the sensor exhibited a low sensitivity to glucose (32 μA mM-1 cm-2) and a good sensitivity to H2O2 (295 μA mM-1 cm-2). In addition, that the prepared electrode could be used to sense the glucose and H2O2 levels in real samples such as blood serum and HeLa cell lines. The screen printed electrode (SPE) immunosensor could sense the E. coli O157:H7 concurrently and quantitatively with a linear range of 1.0 × 101-1.0 × 109 CFU mL-1 and a LOD of 4 CFU mL-1. Likewise, the immunosensor efficiently detect spiked E. coli O157:H7 in milk, chicken, and pork samples, with recoveries ranging from 89.70 to 104.72 %, demonstrating that the immunosensor was accurate and reliable.