We report on studies of new gas sensing devices to be used in high humidity environments. Highly thermal-stable, super hydrophobic 2-dimensional (2D) boron nitride nanosheets (BNNSs) functionalized with Pt nanoparticles were prepared and used as an active layer for the prototype. The morphologic surface, crystallographic structures and chemical compositions of the synthesized 2D materials were characterized by using optical microscope, scanning electron microscope (SEM), transmission electron microscope (TEM) and atomic force microscope (AFM) and Raman scattering, respectively. The experimental data reveals that high-quality BNNSs were prepared. A pair of Au electrodes were combined with a basic electrical circuit and the 2D sensing material to form high-performance gas sensors for the detection of pollution gases. The present structure is simple and the fabrication is easy and fast, which ensures the creation of a low-cost prototype with harsh (high humidity, high temperature) environment resistance and potential for miniaturization. The responses of the prototype to different target gases with different concentrations were characterized. The influences of the operating temperature and bias voltage effect on sensing performances were also investigated. The fabricated sensors appear to have high selectivity, high sensitivity and fast response to target gases. The sensing mechanism in the present case is attributed to the electron donation from the target gas molecules to the active layer, leading to the change of electrical properties on the surface of BNNS layer.

Based on the search for new biodegradable materials that are low cost and easy to synthesize by environmentally friendly methods, we report the use of carrageenan membranes (mixture of κ and λ carrageenans) with different concentrations of titanium dioxide nanoparticles (TiO₂ NPs) and Ni/CeO₂ (10 wt % Ni) for the fabrication of a novel fuel cell electrode for the oxidation of ethanol. Each membrane was characterized to determine its physicochemical properties using X-ray diffraction (XRD), differential scanning calorimetry (DSC), and Fourier transform infrared (FTIR) spectroscopy. Using impedance spectroscopy (IS), a maximum value of 2.08 × 10^-4 S/cm in ionic conductivity was found for the carrageenan nanocomposite with a concentration of 5 wt % TiO₂ NPs (CR5%). Due to its high conductivity values, the CR5% membrane was mixed with Ni/CeO₂ to prepare the working electrode for cyclic voltammetry measurements. Using a solution of 1 M ethanol and 1 M KOH, the oxidation of ethanol over CR5% + Ni/CeO₂ resulted in peak current density values at forward and reverse scan voltages of 9.52 and 12.22 mA/cm², respectively. From our results, the CR5% + Ni/CeO₂ membrane proves to be more efficient in the oxidation of ethanol compared with commercially available Nafion membranes containing Ni/CeO₂.

The development of alga-based biodegradable membranes represents a significant advancement in fuel cell technology, aligning with the need for sustainable material solutions. In a significant advancement for sustainable energy technologies, we have developed a novel biodegradable κ-carrageenan (KC) and boron nitride (BN) nanoparticle membrane, optimized with ammonium sulfate (NHS). This study employed a set of characterization techniques, including thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), where thermal anomalies were observed in the membranes around 160 °C and 300 °C as products of chemical decomposition. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS) revealed the phases corresponding to the different precursors, whose value in the EDS measurements reached a maximum in the KC/BN/NHS5% membrane at 2.31 keV. In terms of the mechanical properties (MPs), a maximum tensile stress value of 10.96 MPa was achieved for the KC/BN sample. Using Fourier transform infrared spectroscopy (FTIR), the physicochemical properties of the membranes were evaluated. Our findings reveal that the KC/BN/NHS1% membrane achieves an exceptional ionic conductivity of 7.82 × 10⁻⁵ S/cm, as determined by impedance spectroscopy (IS). The properties of the developed membrane composite suggest possible broader applications in areas such as sensor technology, water purification, and ecologically responsive packaging. This underscores the role of nanotechnology in enhancing the functional versatility and sustainability of energy materials, propelling the development of green technology solutions.