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

氕探针探索锕系化合物的能量转换功能

• 批准号: 12480139
• 负责人: YAMANAKA Shinsuke
• 金额: $ 9.22万
• 依托单位: OSAKA UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12480139/
• 关键词: energy conversion function; Hydrogen absorption properties; photocatalyst; BaUO_3; UNiAl; SrUO_4; UCoAl; BaZrO_3; SrUO4; Na2U2O7

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.

对BaUO_3、BaZrO_3、Ba（U，Zr）O_3的几种性质之间的关系进行了评价。BaZrO_3表现出典型的钙钛矿型氧化物的倾向，而BaUO_3则表现出玻璃状的倾向。从电阻率、塞贝克系数和热导率三个方面计算了BaUO_3热电材料的无功优值。在298-398 K温度范围内，研究了UNiAl金属间化合物在氢压达2 MPa时的吸氢性能。从所获得的P-C-等温线，氢化物生成的标准焓和熵的估计。热力学数据与以前的比较。通过对ZrO_2和BaZrO_3（ZrO_2的复合氧化物）光催化剂的放氢量的测定，发现UNiAl是一种性能优良的上级储氢材料。在波长为230 nm的光照射下，20 h后ZrO_2的析氢量约为0.07 μmol。而BaZrO_3在230 nm处没有观察到，而在200 nm处观察到。测定了其光电化学性质、平带电位（V_<fb>）和带隙能量（E_g）。结果表明，在太阳能的作用下，ZrO_2的光催化活性比BaZrO_3的光催化活性高上级。UO_2与金属碳酸盐在空气中反应生成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，其催化分解水的活性是P-25催化分解水的活性的1/3。该化合物掺杂NiO的活性是掺杂NiO的NaTaO_3的1/5。