Water molecules bonded to the carboxylate groups at the inorganic-organic interface of an inorganic nanocrystal coated with alkanoate ligands

• 作者: Jiongzhao Li Weicheng Cao Yufei Shu Haibing Zhang Xudong Qian Xueqian Kong Linjun Wang Xiaogang Peng
• 来源期刊: 国家科学评论（英文版）
• 年，卷（期）: 2022,（2）
• 所属期刊栏目: RESEARCH ARTICLES
• 页码范围: 73-82
• 页数: 10页
• 语种: 英文

摘要

High-quality colloidal nanocrystals are commonly synthesized in hydrocarbon solvents with alkanoates as the most common organic ligand.Water molecules with an approximately equal number of surface alkanoate ligands are identified at the inorganic-organic interface for all types of colloidal nanocrystals studied,and investigated quantitatively using CdSe nanocrystals as the model system.Carboxylate ligands are coordinated to the surface metal ions and the first monolayer of water molecules is found to bond to the carboxylate groups of alkanoate ligands through hydrogen bonds.Additional monolayer(s)of water molecules can further be adsorbed through hydrogen bonds to the first monolayer of water molecules.The nearly ideal environment for hydrogen bonding at the inorganic-organic interface of alkanoate-coated nanocrystals helps to rapidly and stably enrich the interface-bonded water molecules,most of which are difficult to remove through vacuum treatment,thermal annealing and chemical drying.The water-enriched structure of the inorganic-organic interface of high-quality colloidal nanocrystals must be taken into account in order to understand the synthesis,processing and properties of these novel materials.