Pt activated SnO₂ nanoparticle clusters were synthesized by a simple solvothermal method for use in highly sensitive ammonia gas sensors.

The stable and crystalline phase of pure nanostructured CeO₂ with various morphologies has been directly synthesized using a cationic surfactant (cetyltrimethylammonium bromide, CTAB) and cerium chloride (CeCl₃·6H₂O) at room temperature by a new, simple, and green chemical precipitation method. Thorough structural characterization techniques, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), electron diffraction, and Raman spectroscopy, were employed to examine the morphology and the microstructure of the final product. The catalytic activity of the nanostructured CeO₂ was tested towards the degradation of the azo dye Congo red (CR). In order to obtain the optimum degradation conditions of CR, the performance of nanostructured CeO₂ with various morphologies (spherical nanoparticles, nanorods, and mixture thereof) for the removal of CR from wastewater was tested under various concentrations of CR dye and quantities of the nanostructured CeO₂. The results show an excellent removal capacity for the organic pollutant CR from wastewater, making it a promising candidate for wastewater treatment.

A gas sensor fabricated with a two-dimensional Ti₃C₂T_X MXene@TiO₂/MoS₂ heterostructure exhibits fast response/recovery time, excellent long-term stability and outstanding selectivity at room temperature, making it a promising candidate for practical detectors of NH₃.