Differences in the catalytic properties of Fe isotopes.

The significant differences in the catalytic properties caused by different 'isotopic catalysts' were discovered for the first time. The commonly purchased Fe2O3 is a 'mixture' of different Fe isotopic oxides which means the catalytic effect of Fe2O3 is theoretically a synthetical result of all isotopic compounds. In this work, the differences in catalytic properties of α-Fe2O3 with natural abundance ratio and separated isotopic α-Fe2O3 (α-54Fe2O3, α-56Fe2O3, and α-58Fe2O3) catalyzing thermal decomposition of ammonium perchlorate (AP) were investigated, and are mainly attributed to the difference in the charge distribution of the nuclei of different iron isotopes. The result suggests that isotope effects in different isotopes when utilized as catalysts are caused by nuclear morphology and the nuclear charge distribution. This study will serve as a base as well as an initiation for future studies of the isotopic catalyst.

Formation of a PVP-protected C/UO2/Pt catalyst in a direct ethanol fuel cell.

In order to solve the problem that UO2 in direct ethanol fuel cell anode catalysts is easily lost in acidic solution, resulting in the degradation of catalytic performance, this paper prepared a C/UO2/PVP/Pt catalyst in three steps by adding polyvinylpyrrolidone (PVP). The test results by XRD, XPS, TEM and ICP-MS showed that PVP had a good encapsulation effect on UO2, and the actual loading rates of Pt and UO2 were similar to the theoretical values. When 10% PVP was added, the dispersion of Pt nanoparticles was significantly improved, which reduced the particle size of Pt nanoparticles and provided more ethanol electrocatalytic oxidation reaction sites. The test results by electrochemical workstation showed that the catalytic activity as well as the stability of the catalysts were optimized due to the addition of 10% PVP.

Research on UO2 modification of a direct ethanol fuel cell Pt/C catalyst.

Radioactive UO2 powder was prepared by hydrothermal method and a set of Pt-xUO2/C catalysts were synthesized by impregnation method for solving the problem of low activity and easy poisoning of anode Pt/C catalysts for a direct ethanol fuel cell. XRD, TEM, EDS, XPS and ICP-MS characterization showed the successful loading of Pt and UO2 onto the carbon carrier. Electrochemical workstation and single cell test results confirm that the catalytic performance of Pt-10% UO2/C is significantly better than Pt/C-eg. It is speculated that the synergistic effect of Pt and U enhances the catalytic activity and UO2 improves the resistance to CO poisoning by releasing O2 stored in the lattice space, while the α-particles released by 235U can also generate radiolysis product OH and promote the oxidative desorption of CO from the Pt surface.

Improved performance of self-reactivated Pt-ThO2/C catalysts in a direct ethanol fuel cell.

A novel self-reactivated catalyst Pt-ThO2/C was prepared for the first time by selecting radioactive material ThO2 as the catalytic additive to address the low activity and toxicity of the anode Pt/C catalyst in a direct ethanol fuel cell. The catalytic activity and resistance to CO poisoning of Pt-6.67 wt%ThO2/C were found to be superior to those of Pt/C-NaBH4 in electrochemical workstation and single-cell tests. It is speculated that the exist of ThO2 not only improves the catalytic activity via the synergistic effect of Pt and Th, but also produces a large amount of radiolysis products, OH radicals, due to 232Th which oxidatively desorbs CO from Pt-COads and solves the CO poisoning problem.