Pillared Layered Compounds: Their Synthesis, Structure, and Properties

本项目将重点研究两个新的多孔材料家族，它们是新合成的，以等电点为特征的，其比表面积为400-600m2/g，孔隙率在10-20A范围内。其中一类是由α，omega-二膦酸在非水溶剂中与金属相互作用制备的有机-无机杂化化合物。这些化合物在由膦酸烷基基或芳基连接的类似金属磷酸盐的层的框架内包含空洞。芳基易于被磺酸基团官能化，从而转化为高活性的Bronsted酸。其目的是现在提供各种功能，控制这些产品的疏水-亲水特性和孔径。我们将探讨这些化合物的吸附分离能力和催化行为，包括它们的化学选择性和尺寸选择行为。第二类多孔材料由过渡金属氧化物与二氧化硅或氧化锆组合而成，在酒精中用己胺模板制备的孔在10-20A范围内。这两个家族在沸石和新型介孔材料之间架起了一座桥梁。因此，它们应该满足分离科学、离子交换、传感器和催化等其他材料不适合的需求。这些材料的结构和表征将需要使用广泛的光谱、衍射和表面工具，为学生提供充分的机会，使用最新的材料化学技术的科学设备进行培训。这项研究将与西班牙、波兰和印度的研究小组合作。%多孔材料在基于尺寸的分子分离方面具有多种用途，在催化、传感器、药物输送、离子交换和纳米科学中具有广泛的用途。其中最好的例子是沸石，它被广泛用于大多数这些目的，但最著名的是在石油裂解中提高汽油和家庭取暖油的产量。缺点是它们有用的空腔很小，不到1纳米(Nm)或百万分之一英寸。十年前，一类新的无机多孔材料被发现，它们的孔分布在2到15 nm范围内，具有许多潜在的用途。已经发现了两类新的孔材料，孔在1到2 nm范围内，这正是很大程度上缺少的尺寸。一组材料包含有机和无机基团，可以改变以吸引不同类别的中等大小分子用于分离、药物输送和催化转化。第二类是完全无机的，主要用于催化，因为几乎任何催化活性的金属氧化物都可以以这种形式制备。这项研究需要培养学生利用科学设备和材料化学的最新技术。这项研究将得到与西班牙、波兰和印度的团体以及德克萨斯农工大学本科生、研究生和博士后的合作。

This project will focus on two new families of porous materials, newly synthesized and characterized by the PI, with surface areas of 400-600 m2/g and pores in the range of 10-20A. One family consists of organic-inorganic hybrids prepared from alpha, omega-diphosphonic acids interacting with metals in non-aqueous solvents. These compounds contain cavities within a framework of metal phosphate like layers bridged by alkyl or aryl groups of the phosphonic acid. The aryl groups are amenable to functionalization by sulfonic acid groups which converts them into highly reactive Bronsted acids. The aim is to now provide a variety of functionalities, control hydrophobic-hydrophilic character and pore size of these products. The sorption and separation capabilities and catalytic behavior of the compounds as to their combined chemical selectivity and size selective behavior will be probed. The second family of porous materials consists of transition metal oxides-combined with either silica or zirconia also with pores in the 10-20A range prepared in alcohol with hexylamine templates. These two families bridge the gap between zeolites and the new mesoporous materials. They should therefore serve needs in separations science, ion exchange, sensors and catalysis for which other materials are unsuitable. The structure and characterization of these materials will require the use of a broad spectrum of spectroscopic, diffraction and surface tools providing ample opportunities for students to be trained using state of the science equipment in the latest techniques of materials chemistry. This study will be assisted by collaboration with groups in Spain, Poland and India.%%% Porous materials have a variety of uses in separating molecules based upon size, have extensive use in catalysis, sensors, drug delivery, ion exchange and nanoscience. Among the best examples are zeolites, used extensively for most of these purposes but best known as improving the yield of gasoline and home heating oil in petroleum cracking. A disadvantage is that their useful cavities are small, less than 1 nanometer (nm) or one millionth of an inch. A decade ago a new family of inorganic porous materials was discovered with narrow distribution of pores in the 2 to 15 nm range and many potential uses.Two new families of porous materials with pores in the 1 to 2 nm range, just the size that has largely been missin, has been discovered. One group of materials contain organic as well as inorganic groups and can be altered to attract different classes of medium sized molecules for separations, drug delivery and catalytic transformations. The second group is totally inorganic to be used mostly in catalysis as almost any catalytically active metal oxide can be prepared in this form. This research will require the training of students to utilize the state of the science equipment and the latest techniques of materials chemistry. The research will be assisted by collaboration with groups in Spain, Poland and India as well as undergraduates, graduate students and post-doctoral students at Texas A&M University.