基于单层矿物纳米片超晶格结构复合功能材料的可控组装及其性能研究

Layer-structured mineral materials have unique layered structure and chemical reaction characteristics in the interlayer galleries, which can be artificially exfoliated into unilamellar nanosheets with multiple functionalities via chemical exfoliation procedures. Unilamellar nanosheets, with a molecular-level thickness of about 1 nm versus two-dimensional (2D) lateral size ranging from submicrometer to several tens of micrometers, can be regarded as a new and very important class of mineral materials. Unilamellar nanosheets can also be serve as a basic building block for superlattice-like molecular-scale assembly to prepare functional materials with high quality, which provides a broad research space for the design and function development of mineral materials. This work aims to systemically explore the nove route of chemical exfoliation and intercalation of the layer-structured mineral materials; to prepare unilamellar nanosheet with specific composition and function through chemical exfoliation of the new-type layered mineral materials; to fabricate functional materials with high quality based on layer-by-layer (LBL) self-assembly and/or Langmuir-Blodgett (LB) technique in molecule scale; particularly to integrate unilamellar nanosheet of cationic-type with anion-type clay mineral (high specific surface area) for composite multilayer; to precise control of the hierachical nanostructure, and exact determination of interfacial composition and active sites and explore their nove physical and chemical properties; to reveal the assembly rules and the basic principles of unilamellar mineral materials nanosheet for the design and preparation of the new-type unilamellar nanosheet-based functional materials. The work will be expected to promote our scientific research level on the chemical exfoliation, and molecular-scale assembly of layer-structured mineral materials and form a cutting-edge research area both scientifically and internationally competitive.

层状结构矿物材料具有独特的层状结构和层间化学反应特性，通过化学剥离反应，可创建具有多种功能的单层矿物纳米片。单层矿物纳米片具有分子水平的二维尺度，可作为组装基元进行超晶格结构组装制备复合功能材料，这为矿物材料的设计和功能开发提供了广阔的研究空间。本工作旨在系统探索层状结构矿物材料化学剥离的新方法，创建一系列具有特定组成及功能的单层矿物纳米片；采用LBL及LB技术，实现单层矿物纳米片基复合功能材料的可控组装，尤其阳离子型粘土矿物单层纳米片/阴离子型粘土矿物单层纳米片超晶格结构复合功能材料；基于多层次超晶格结构的精确调控，探究单层矿物纳米片组装过程中的基本原理和协同规律，揭示其界面组成、活性点分布规律，发掘其优异的理化特性及性能复合增强效应的本质，为层状结构矿物材料的系统设计、结构调变与功能化提供实验与理论基础。该工作有助于提升我国在层状结构矿物材料研究方面的科学水平，形成研究优势和国际影响。

本项目开展以来，我们探索与发展新型层状氢氧化物剥离的新方法，并对层状氢氧化物单层纳米片的可控组装及超晶格结构复合功能材料的性能进行了系统研究。发展了层状氢氧化物的剥离方法，实现了氢氧化物纳米片单层到双层的精准控制。研究发现，单层Mg-Al LDH纳米片的氢氧根离子传导率是目前报道的阴离子导体中传导率最高的材料，可与商用Nafion质子交换膜的质子传导率相比拟；双层氢氧化物纳米片表现出优于单层纳米片的高催化析氧反应活性；通过正电性单层氢氧化物与负电性氧化物、石墨烯等纳米片静电自组装成功构筑超晶格结构复合材料，在电催化、荧光等应用中表现出性能增强作用，相关研究为单层矿物纳米片基复合材料的设计、制备与功能化应用提供了实验与理论基础。在国家自然科学基金的资助下，课题负责人以通讯作者发表研究论文54篇，其中在Journal of the American Chemical Society发表论文1篇，Advanced Functional Materials发表论文1篇，ACS Nano发表论文1篇，Advanced Energy Materials发表论文2篇，Applied Catalysis B: Environmental发表论文1篇、Materials Horizons发表论文1篇。