在质子交换膜电解剂中,高效的酸演化在硫化马卡西特类型电催化剂上
Xiao-Long Zhang1, Peng-Cheng Yu1, Xiao-Zhi Su2
1Division of Nanomaterials & Chemistry, Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, China.
Science advances
|July 5, 2023
概括
研究人员开发了一种新的白金组无金属催化剂,用于质子交换膜 (PEM) 水电解. 这种含硫催化剂在酸性条件下表现出高活性和稳定性,降低了生产的成本.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 催化剂是一种催化剂.
背景情况:
- 质子交换膜 (PEM) 水电解器严重依赖昂贵的组金属 (PGM) 催化剂.
- 开发具有成本效益的,没有PGM的替代品,在酸性介质中具有足够的活性和稳定性,对于大规模部署至关重要.
研究的目的:
- 在酸性环境中设计一种新的无PGM催化剂,用于演化反应 (HER).
- 调查硫对二的结构和电子特性的影响,以提高催化性能.
主要方法:
- 合成 pyrite 类型的脱化物和随后的硫剂以诱导结构转变.
- 描述催化剂的结构,组成和电子特性.
- 在酸性溶液和PEM电解器中对HER的催化剂性能进行电化学评估.
主要成果:
- 硫注射诱导了由化类型的化转化成标石结构的相变.
- 由此产生的马卡西特催化剂在10mA/cm2时表现出低超电位67mV的HER.
- 催化剂表现出极好的稳定性,在 1000 小时的酸性测试后没有降解,在 PEM 电解器中稳定运行超过 410 小时.
结论:
- 硫注射是一种有效的策略,可以从化类型的化中创建抗酸的马卡西特结构.
- 量身定制的电子状态和坚固的结构显著增强扩散和电催化活性.
- 这种无PGM的催化剂提供了一个有前途的,具有成本效益的解决方案,通过PEM水电解来有效地生产.
相关概念视频
01:22Electrophilic Aromatic Substitution: Sulfonation of Benzene
6.2K
Sulfonation of benzene is a reaction wherein benzene is treated with fuming sulfuric acid at room temperature to produce benzenesulfonic acid. Fuming sulfuric acid is a mixture of sulfur trioxide and concentrated sulfuric acid.
6.2K
01:13Esters to Carboxylic Acids: Acid-Catalyzed Hydrolysis
3.0K
Hydrolysis of esters under acidic conditions proceeds through a nucleophilic acyl substitution. In the presence of excess water, the reaction proceeds in a reversible manner, forming carboxylic acids and alcohols.
During hydrolysis, the ester is first activated towards nucleophilic attack through the protonation of the carboxyl oxygen atom by the acid catalyst. The protonation makes the ester carbonyl carbon more electrophilic. In the next step, water acts as a nucleophile and adds to the...
During hydrolysis, the ester is first activated towards nucleophilic attack through the protonation of the carboxyl oxygen atom by the acid catalyst. The protonation makes the ester carbonyl carbon more electrophilic. In the next step, water acts as a nucleophile and adds to the...
3.0K
01:17Ion Exchange
624
Ion exchange chromatography separates charged molecules from a solution by reversibly exchanging them with mobile, or 'active', ions associated with the oppositely charged stationary phase. This method can be used to separate ions, soften and deionize water, and purify solutions. The polymers comprising the ion-exchange column are high-molecular-weight and chemically stable polymers, crosslinked to be porous and essentially insoluble. They are also functionalized with either acidic or...
624
02:17Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
3.4K
Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
3.4K
02:26Preparation and Reactions of Sulfides
4.9K
Sulfides are the sulfur analog of ethers, just as thiols are the sulfur analog of alcohol. Like ethers, sulfides also consist of two hydrocarbon groups bonded to the central sulfur atom. Depending upon the type of groups present, sulfides can be symmetrical or asymmetrical. Symmetrical sulfides can be prepared via an SN2 reaction between 2 equivalents of an alkyl halide and one equivalent of sodium sulfide.
4.9K
02:50Catalysis
27.1K
The presence of a catalyst affects the rate of a chemical reaction. A catalyst is a substance that can increase the reaction rate without being consumed during the process. A basic comprehension of a catalysts’ role during chemical reactions can be understood from the concept of reaction mechanisms and energy diagrams.
27.1K