Showcasing the Potential of Iron-Doped Electrolytes to Enhance the Ionic Conduction for a Low-Temperature Ceramics Fuel Cell

In recent studies, fast ionic conduction through doping and coating is a favorite subject and indicated a promising and stable strategy to optimize ions in the developed electrolytes for low-temperature ceramic fuel cells (LT-CFCs). Using the sol–gel technique, we designed a doped spinel electrolyte (Fe-CoAl2O4) to further enhance ionic properties. The prepared CFA (CoFe0.25Al1.75O4) was used as an electrolyte sandwiched between symmetrical electrodes and delivered stunning fuel cell performance (810 mW/cm2) with better stability at the low operating temperature of 520 °C compared to other compositions of CFA. The low grain boundary resistance manifests CFA’s high ionic conduction + microstructural properties, assisting with higher fuel cell performance. The appropriate doping of Fe reduces the energy bandgap, enhancing the charge transport through energy band alignment. Moreover, the Schottky junction phenomena were proposed to support high ionic conduction without any short-circuiting issue. This work thus points out an exciting electrolyte with a different working mechanism from previous studies. It indicates a feasible approach to developing high-performing and stable electrolytes for LT-CFCs

Modified fiber optic sensor for highly precise identification of mercuric ion (Hg2+) concentrations in aqueous solution

A fiber optic sensor for monitoring mercuric (Hg2+) ions in the aqueous sample have been developed based on modified cladding. To fabricate a D-shaped sensing zone onto the multimode optical fiber lengthwise polishing was utilized using a mechanical end and edge polishing system. The produced sensing region has dimensions of 10 mm × 125 μm × 62 μm (l × w × h). A 2 μm thin layer of Al2O3 nanoparticles sensitized with 4-(2-pyridylazo)-resorcinol was deposited onto the sensing element of multimode fiber optic sensor to make it sensitive and selective for Hg2+ ions. The analytical results demonstrate that the sensing device has a linear response for Hg2+ ions concentration over a range from 4 to 16 ppm along with a 4 ppm limit of detection in an aqueous sample at room temperature. The selectivity of the sensor is examined for the recognition of Hg2+ ions in presence of other cations such as zinc and/or lead ions up to 16 ppm in an aqueous solution. The main merits of this fabricated sensor are easy and safe installation, rapid response, enhanced linear response range, and better selectivity towards Hg2+ ions