固态氧化物电解池中碳-分子电化学转化为可再生燃料

近年来,随着社会环保意识的迅速提高以及对可再生能源利用能力的大幅增强,以燃料电池和电解池为代表的电化学技术已经逐渐在能源的存储、转化和利用方面发挥着不可或缺的独特作用.其中,固态氧化物电解池经过多年的发展,在装置成本和工作效率上取得了长足的进步,在储能转化方面具有重要的潜力.与此同时,伴随着《巴黎协定》签订以来各国的“碳中和”路线图逐渐出台,利用相对廉价易得的可再生电能,将二氧化碳(CO₂)和甲烷(CH₄)等碳-(C1)分子电解转化为高附加值的可再生燃料(如水煤气、乙烯等),对于碳中和目标的实现具有重要的意义.因此,C1分子电化学转化的研究成为了当下重点关注的研究领域,许多重要的研究成果和技术进步在过去几年中不断涌现.固态氧化物电解池作为一种代表性的C1分子电解和转化平台,也日渐引起相关领域研究人员的关注和兴趣.与传统的C1分子催化转化方法相比,基于固态氧化物电解池的电解转化技术具有两个重要优点:高能量转换效率与体系抗中毒能力.这两个特性作为体系稳健性的基石,保障了C1分子转化为可再生燃料的反应过程的长期可持续性.本文首先简要回顾了固态氧化物电解池的前沿技术与发展,并从电解池系统分类、反应体系的特征和反应体系发展的前景与挑战这三个方面,简要介绍了近年来基于固态氧化物电解池体系的C1分子电化学转化的代表性工作.CO₂与CH₄作为廉价易得的C1分子的代表,其转化因其反应分子惰性及反应过程不可控性而广受研究者关注,本文重点关注了在固态氧化物电解池中CO₂,CO₂/H₂O和CH₄三个体系的电化学反应过程和近期研究进展,希望可为相关研究人员未来设计更合适的催化剂和构建更优的电解池结构提供有益的参考.本文还针对目前固态氧化物电解池体系在C1分子转化领域所面临的挑战,提出了未来的一些可能的研究方向,以期助力研究者在不远的将来实现C1分子电解生产可再生燃料的实用化.     

K X-ray relative transition probabilities for 23≤Z≤33

The K X-ray relative transition probabilities K_b/K_a of some elements for atomic numbers 23Z33 induced by 3 MeV protons were measured. The experimental results are compared with the relativistic Hartree-Fock (RHF) calculations. Good agreements have been obtained considering the experimental error.     

Transfer ionization cross-sections measured in collisions of highly charged argon ions with neon target

: Multiple electron transfer processes are studied for Arq+n- Ne (q= 8, 9, 11, 12) collisions by using multi-parameter coincidence techniques. Various electron transfer processes are identified experimentally and the related cross-sections are measured. The dependence of transfer ionization cross-sections on the recoil charge states is compared with the results from the modified molecular classical overbarrier model. It is found that the modified model described the experimental results reasonably.     

Simple model for the ionization of helium atoms by fully and partially stripped ions in the strong interaction region

Theoretical calculations employing the modified over-barrier model to investigate single and double ionization cross sections of helium in collisions with highly charged ions are presented in the strong perturbation region. It shows the velocity and charge state dependences of cross sections, which coincides with the available experimental data. In order to determine the reliability of this model for partially stripped projectiles, the cross-section ratios have been measured for CZp+, OZp+-He (Zp=1-4) by the coincidence technique in the velocity range of 1-4.5 a.u. The calculated results are approximately in agreement with the experimental data.     

Photo-Driven Quasi-Topological Transformation Exposing Highly Active Nitrogen Cation Sites for Enhanced Photocatalytic H2O2 Production

Herein, the exposure of highly-active nitrogen cation sites has been accomplished by photo-driven quasi-topological transformation of a 1,10-phenanthroline-5,6-dione-based covalent organic framework (COF), which contributes to hydrogen peroxide (H₂O₂) synthesis during the 2-electron O₂ photoreduction. The exposed nitrogen cation sites with photo-enhanced Lewis acidity not only act as the electron-transfer motor to adjust the inherent charge distribution, powering continuous and stable charge separation, and broadening visible-light adsorption, but also providing a large number of active sites for O₂ adsorption. The optimal catalyst shows a high H₂O₂ production rate of 11965 μmol g⁻¹ h⁻¹ under visible light irradiation and a remarkable apparent quantum yield of 12.9 % at 400 nm, better than most of the previously reported COF photocatalysts. This work provides new insights for designing photo-switchable nitrogen cation sites as catalytic centers toward efficient solar to chemical energy conversion.     

Scattering of SH-wave by an elliptical inclusion with partial debonding curve in half-space

For the purpose of revealing the dynamic properties of elliptical inclusion in the half-space, solving the problem of scattered SH-wave, the method of ‘conformal mapping’ is used to map an elliptical inclusion into a circular inclusion. The displacement field and the stress field of the elliptical inclusion while bearing out-plane line source load are obtained by Green’s function method. Then, infinite system of linear equations is established by displacement and stress continuous boundary conditions, to solve unknown coefficients of wave function. Finally, the ‘partial debonding curve model’ is constructed, and the equal stress but opposite in direction is applied in the partial debonding curve. It is obtained the total displacement field of the elliptical inclusion with a partially debonding curve in the half-space. Numerical results demonstrate that dynamic stress concentration factor is influenced in the incident angle, the frequency of incident wave, the depth of inclusions and the partial debonding curve angle.     

X-ray spectra induced in highly charged 40Arq+ interacting with Au surface

By use of optical spectrum technology, the spectra of X-ray induced by highly charged ⁴⁰Ar ^q+ ions interacting with Au surface have been studied. The results show that the argon Kα X-ray were emitted from the hollow atoms formed below the surface. There is a process of multi-electron exciting in neutralization of the Ar¹⁶⁺ion, with electronic configuration 1s² in its ground state below the solid surface. The yield of the projectile Kα X-ray is related to its initial electronic configuration, and the yield of the target X-ray is related to the projectile kinetic energy.     

A cyclic tetra-nuclear dinitrosyl iron complex [Fe(NO)2(imidazolate)]4: synthesis, structure and stability

A novel cyclic tetra-nuclear dinitrosyl iron complex [Fe(NO)2(Im-H)]4 was isolated and characterized by X-ray crystallography, and in donor solvents this fragments into 17 e- monomeric units that give EPR spectra analogous to the g= 2.03 species seen in mammalian biology.     

考虑弯曲和轴向振动模态的一维梁压电阻抗模型及试验研究

同时考虑一维梁结构的弯曲和轴向振动,对其压电阻抗模型进行建模分析和试验验证。在0.02～42 kHz频段内区分并标记了一维钢梁弯曲振动模态前18阶及轴向振动模态前3阶。结果表明:在0.02～7.5kHz频段内,数值计算和试验结果中谐振峰对应频率的相对误差较大:11.7%～16.5%,其原因可能是低频时振动能量较低且波的传播受结构阻尼、边界条件及环境噪音等因素影响较为明显;在7.5～42kHz范围内,两者谐振峰位置符合良好,相对误差较小:0.11%～2.31%,表明该模型在高频段具有较好的适用性;轴向振动模态对应频率大于弯曲振动模态。本研究为结构健康监测过程中检测频段的选取及损伤信息的提取提供参考。