Exploration of the energy conversion function of actinide compounds by protium probe

研究了BaUO_3、BaZrO_3、Ba(U，Zr)O_3的几种性能之间的关系。BaZrO_3呈现典型的钙钛矿型氧化物倾向，而BaUO_3呈现玻璃状倾向。从材料的电阻率、塞贝克系数和导热系数三个方面评价了BaUO_3热电材料(ZT)的无量纲优值。在298-398K温度范围内，对金属间化合物的吸氢性能进行了测试，并根据测得的P-C等温线估算了氢化物的标准生成焓和标准生成熵。并与前人的热力学数据进行了比较。结果表明，UNiAl是一种较好的吸氢材料，并测定了催化剂的析氢量，包括氧化锆和氧化锆复合氧化物。在230nm光的照射下，20h后，ZrO2的析氢量约为0.07μ摩尔。而在230 nm处没有观察到BaZrO_3，而在200 nm处观察到了BaZrO_3。测量了薄膜的光电化学性能、平带电势(V&lt；Fb&gt；)和带隙能(Eg)。结果表明，在太阳能的作用下，ZrO_2的光催化活性优于BaZrO_3。UO_2与金属碳酸盐在空气中反应生成了SrUO_4、CaUO_4、K_2U_2O_7和Na_2U_2O_7。SrUO_4是一种优良的光催化剂，其裂水活性仅为掺杂铂的P-25的1/3。这种掺杂NiO的化合物的活性是掺杂NiO的NaTaO_3的五分之一。

Relationships between several properties of BaUO_3, BaZrO_3, Ba(U,Zr)O_3 were evaluated. BaZrO_3 shows typical tendencies of perovskite type oxides, while BaUO_3 shows glass-like tendencies. Dimensionless figure of merit for thermoelectric materials (ZT) of BaUO_3 was evaluated from the electrical resistivity, Seebeck coefficient, and thermal conductivity. It is found that BaUO_3 has a potential to be a good thermoelectric material.Hydrogen absorption properties of UNiAl intermetallic compound are examined at hydrogen pressures up to 2MPa, and temperatures between 298-398 K. From the obtained P-C-isotherms, the standard enthalpy and entropy of hydride formation are estimated. The thermodynamic data are compared with previous ones. It is found that UNiAl is a superior candidate for hydrogen absorption materials.The amount of evolved H_2 gas of photocatalysts such as ZrO_2 and BaZrO_3 (compound oxide of ZrO_2) was measured. H_2 evolution of ZrO_2 was about 0.07 μmol after 20 hours under the wavelength of irradiation light was 230 nm. But that of BaZrO_3 was not observed in the case of 230 nm but was observed in the case of 200 nm. Photoelectrochemical properties, flat-band potential (V_<fb>) and bandgap energy (E_g) were measured. From these results, it was found that the photocatalytic activity of ZrO_2 was superior to that of BaZrO_3 under the use of solar energy. SrUO_4, CaUO_4, K_2U_2O_7 and Na_2U_2O_7 were formed by the reaction of UO_2 and metal carbonates in air. SrUO_4 is an excellent photocatalyst and the activity of water splitting for this uranium complex oxide doped with Pt was one third of that for P-25 doped with Pt. The activity for this compound doped with NiO was one fifth of that for NaTaO_3 doped with NiO.