调节溶解的光酸作为稳定的光驱动pH开关,用于CO2捕获和释放
Anna de Vries1, Kateryna Goloviznina2, Manuel Reiter1
1Electrochemical Energy Systems Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, 8092 Zurich, Switzerland.
Chemistry of materials : a publication of the American Chemical Society
|February 22, 2024
概括
光酸,光激活的质子释放剂,在特定溶剂混合物中表现出增强的稳定性和溶解性. 这一突破提高了它们在光驱二氧化碳捕获等应用中的性能.
科学领域:
- 摄影化学的使用.
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 光酸是有机分子,在照明时释放质子,使光控制的pH调整成为可能.
- 现有的光酸,如质子化梅洛,具有有限的水解稳定性和水溶液中的溶解性差,阻碍了CO2捕获等应用.
- 这些限制限制了可逆pH循环的效率和持续时间.
研究的目的:
- 通过修改其溶解环境,提高光酸的稳定性和溶解性.
- 调查二元溶剂混合物对光酸性能的影响,特别关注梅洛.
- 评估改进的光酸在光驱二氧化碳捕获方面的潜力.
主要方法:
- 使用二元溶剂混合物调整 merocyanine 光酸的溶解环境.
- 比较pH调节大小和稳定性 merocyanine 在纯水与二元溶剂混合物.
- 在优化的溶剂系统中评估光酸的长期循环稳定性.
主要成果:
- 与纯水相比,通过阿普罗特溶剂分子的优先溶解显著增加了60%的pH调节大小.
- 经过修改的光酸在350多小时内表现出稳定的循环,这显著改善了化学稳定性.
- 这种方法绕过了复杂的分子结构修改的需要.
结论:
- 在二元溶剂混合物中的溶解环境的战略调整大大提高了光酸的稳定性和可溶性.
- 在优化的溶剂混合物中,美洛酸光酸显示出显著的性能增长,超过350小时的稳定循环.
- 这项工作代表了光酸在光驱二氧化碳捕获技术中的应用的关键里程碑.
相关概念视频
04:01Factors Affecting Solubility
33.4K
Compared with pure water, the solubility of an ionic compound is less in aqueous solutions containing a common ion (one also produced by dissolution of the ionic compound). This is an example of a phenomenon known as the common ion effect, which is a consequence of the law of mass action that may be explained using Le Chȃtelier’s principle. Consider the dissolution of silver iodide:
33.4K
01:10Acid–Base Equilibria: Activity-Based Definition of pH
586
For an ideal solution, the pH is defined as the negative logarithm of the hydrogen ion concentration. For a non-ideal solution, an accurate measurement of the pH must consider the negative logarithm of the hydrogen ion activity rather than concentration. In such a solution, the pH can be more accurately defined as the negative logarithm of a product of the hydrogen ion concentration and its activity coefficient.
In solutions of very low ionic strength—for example, pure water—the...
In solutions of very low ionic strength—for example, pure water—the...
586
01:29Leveling Effect
804
In acid-base chemistry, the leveling effect refers to the limitation imposed by the solvent on the strength of acids and bases in solution. When a base stronger than the solvent's conjugate base is used, it deprotonates the solvent until the base is entirely consumed, making it ineffective against weaker acids. Conversely, an acid stronger than the solvent's conjugate acid protonates the solvent until the acid is depleted, rendering it ineffective against weaker bases. Essentially, the...
804
02:30Water: A Bronsted-Lowry Acid and Base
50.5K
The reaction between a Brønsted-Lowry acid and water is called acid ionization. For example, when hydrogen fluoride dissolves in water and ionizes, protons are transferred from hydrogen fluoride molecules to water molecules, yielding hydronium ions and fluoride ions:
50.5K
00:53Extraction: Effects of pH
486
Consider a neutral form of an amine, B, with a partition coefficient, K, in a liquid mixture containing organic and aqueous phases. The pH of the aqueous phase affects the charge on acidic and basic solutes, and the charged form is usually more soluble in the aqueous phase. Suppose the conjugate acid form of the amine is soluble only in the aqueous phase while the base form is soluble in both phases. Then the distribution coefficient, D, can be given as the ratio of amine concentration in the...
486
01:16Titration in Nonaqueous Solvents
795
Most acid-base titrations are performed in an aqueous medium. In aqueous titrations, water competes with weaker acids or bases for proton donation or acceptance, leading to ambiguous endpoints in the titration curve. Water also affects the partial ionization of weak acids or bases. For example, water accepts a proton from acetic acid to form hydronium and acetate ions. The hydronium ion formed is a stronger acid than acetic acid, and the acetate ion is a stronger base than water. As a result,...
795