通过调节Pt-TiO相互作用来调整Ti-OH物种的布伦斯特德酸度
Fanchun Meng1,2, Xinchun Yang1,2, Shichao Zhao1
1State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, 030001, China.
ChemSusChem
|December 20, 2023
概括
这项研究表明,通过原子层沉积控制金属支相互作用,精确地调节双功能催化剂中的界面酸位. 这种控制增强了酸化等反应的催化活性.
科学领域:
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
- 表面化学 表面化学
背景情况:
- 具有金属和酸位的双功能催化剂对于许多化学反应至关重要.
- 界面酸位显著影响反应中间体,但它们的控制仍然具有挑战性.
- 金属支相互作用 (MSI) 对界面酸位的影响尚不清楚.
研究的目的:
- 为了研究金属支相互作用 (MSI) 对双功能催化剂界面酸位的影响.
- 通过调整MSI,精确控制界面酸位的产生和数量.
- 为了确定界面酸度和催化性能之间的相关性.
主要方法:
- 使用不同TiO2纳米层厚度 (m) 的原子层沉积 (ALD) 制备Pt-mTiO2/α-Al2O3催化剂.
- 催化剂的表征分析金属支相互作用和酸位属性.
- 用酸 (LA) 化作为模型反应对催化活性的评估.
主要成果:
- 新的布伦斯特德酸位点是通过Pt-TiO2相互作用生成的,其酸度是根据TiO2纳米层厚度精确调整的.
- 对LA化的催化活性与Ti-OH物种含量 (布伦斯特酸位) 呈现出强烈的线性相关性.
- 具有最高酸位含量 (0.486 mmol/g) 的Pt-40TiO2 / α-Al2O3催化剂显示出最佳的催化性能.
结论:
- 原子层沉积 (ALD) 提供了对金属支相互作用 (MSI) 的精确控制,以调节界面酸位.
- 在Pt-TiO2接口上产生Ti-OH物种是由溢出和水分离促进的.
- 通过控制的MSI调整界面酸度是提高双功能催化剂性能的有效策略.
相关概念视频
01:26Acid–Base Titration: Overview
10.5K
An acid-base titration is a technique used to determine the concentration of an unknown acid or base, using a titrant of known concentration–either a base for acid titration or an acid for base titration. The process involves gradually adding the titrant, leading to a predictable change in the pH of the solution. This change is plotted on a titration curve, showing how a solution's pH varies with the amount of titrant added. Such curves are instrumental in monitoring the...
10.5K
01:16Titration in Nonaqueous Solvents
806
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,...
806
01:17Solution Composition During Acid/Base Titrations
586
The titration of a weak acid with a strong base results in the formation of water and the conjugate base of the acid. For instance, titrating acetic acid with sodium hydroxide leads to the formation of water and sodium acetate. A solution of acetic acid and sodium acetate constitutes a buffer whose relative concentration at different stages of the titration is indicated by the α values, which represent percentages of the weak acid and its conjugate base.
The α0 and α1 values...
The α0 and α1 values...
586
01:18Titration of Polyprotic Base with a Strong Acid
801
The titration of a polyprotic base such as sodium carbonate with a strong acid such as hydrochloric acid results in two equivalence points on the titration curve. At the first equivalence point, the carbonate ions in the base are completely converted to bicarbonate ions. The second equivalence point corresponds to the complete conversion of bicarbonate ions to carbonic acid, which dissociates into carbon dioxide and water. The region before the first equivalence point corresponds to the...
801
01:23Titration of Polyprotic Acids with a Strong Base
1.8K
Titration of a polyprotic acid, which contains multiple ionizable protons, involves distinct dissociation steps, each with its own dissociation constant (Ka). Each successive Ka is weaker than the previous one. In the titration of a polyprotic acid like sulfurous acid with a strong base such as sodium hydroxide, the base first neutralizes the initial ionizable proton, forming an intermediate species (e.g., hydrogen sulfite ions). This step's titration curve resembles that of a weak...
1.8K
03:55Titration Calculations: Weak Acid - Strong Base
44.3K
Calculating pH for Titration Solutions: Weak Acid/Strong Base
For the titration of 25.00 mL of 0.100 M CH3CO2H with 0.100 M NaOH, the reaction can be represented as:
For the titration of 25.00 mL of 0.100 M CH3CO2H with 0.100 M NaOH, the reaction can be represented as:
44.3K