To investigate the variation in the radiation stability of ceria with microstructure under the electronic excitation regime, ceria samples sintered under different conditions were irradiated with high energy 100 MeV Ag ions. The ceria nanopowders were synthesized and sintered at 800 °C (S800), 1000 °C (S1000) and 1300 °C (S1300), respectively. The samples with widely varying grain size, densities and microstructure were obtained. The pristine and irradiated samples were studied by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). None of the samples amorphized up to the highest fluence of 1 × 10(14) ions per cm(2) employed in this study. XRD and Raman studies showed that the sample with lowest grain size suffered maximum damage while the sample with largest grain size was most stable and showed little change in crystallinity. Raman spectroscopy indicated the enhanced formation of Ce(3+) and related defects in the sample with larger grain size after irradiation. The most intriguing result was the absence of Ce(3+)-related defects in the sample with lowest grain size which actually showed maximum damage upon irradiation. The XPS studies on S800 and S1300 provided concrete evidence for the presence of Ce(3+) and oxygen ion vacancies in S1300. The grain boundaries and grain size dependent stability have been discussed.
We introduce a hybrid two‐dimensional nanointerface structure for bioelectronic systems. We fabricated smart hierarchically self‐assembled 2D electrobiocatalytic interface system based on the combination of gold nanoparticles doped graphene oxide (GO)‐molybdenum disulfide (MoS2) layered nanohybrid, conjugated with poly (N‐isopropylacrylamide, PNIPAAm) resulting in GO/AuNPs/MoS2/PNIPAAm interface. Horseradish peroxidase (HRP) was subsequently immobilized on the GO/AuNPs/MoS2/PNIPAAm interface through electrostatic interactions giving GO/AuNPs/MoS2/PNIPAAm/Peroxidase electrobiocatalytic interface system as a platform for electrobiocatalysis reactions for biosensing and bioelectronic applications. The electrobiocatalytic activity of the nanohybrid interface structure was studied using hydrogen peroxide (H2O2) as a model analyte. Cyclic Voltammetry showed diffusion controlled electron transfer properties at the interface. The fabricated bioelectrode exhibits a wide linear response to the detection of H2O2 from 1.57 to 11.33 mM, with a detection limit of 3.34 mM (S/N=3) and a capacitance of 8.6 F/cm2.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.