Omar Yaghi

Omar M. Yaghi

Title
Professor
Department
Dept of Chemistry
Phone
(510) 643-5507
Research Expertise and Interest
chemical framework, metal-organic frameworks, covalent organic frameworks, gas storage systems, water harvesting from desert air.
Research Description

We are developing the science of building chemical structures from molecular building blocks; a field we refer to as Reticular Chemistry. It is concerned with linking of molecular building blocks (organic molecules, inorganic clusters, dendrimers, peptides, proteins,...) into predetermined structures in which such units are repeated and are held together by strong bonds. This research has led to the discovery of several classes of porous crystalline materials: metal-organic frameworks, covalent organic frameworks, and zeolitic imidazolate frameworks (MOFs, COFs, and ZIFs). In practice, this kind of chemistry requires a multi-disciplinary approach involving inorganic synthesis of metal complexes and frameworks, organic synthesis of the linkers and synthetic modification of frameworks' interior, solid-state and solution synthesis, and the characterization techniques associated with these diverse areas ranging from electron microscopy, NMR, X-ray crystallography, neutron diffraction to gas adsorption isotherm measurements. We design open frameworks to have ultrahigh porosity (up to 6,000-10,000 meter square per gram) exceeding traditional porous materials such as zeolites, mesoporous silica and carbon; making MOFs, COFs and ZIFs useful for clean energy storage and generation.

Presently, we are able to design the structure of the frameworks, their functionality, and the pore environment and metrics to produce crystalline materials capable of storage and separation of hydrogen, methane, carbon dioxide, water, volatile organics, peptides and proteins. The ability to functionalize the interior of the pores also results in enzyme-like active sites installed within the confines of such MOF structures for their use in catalysis of reactions leading to clean energy generation: conversion of methane to methanol, water to hydrogen and oxygen, organic cyclization reactions, and carbon-carbon bond breaking reactions.

We have also made progress in transferring this precise control in building frameworks to the design of nano-MOFs and the development of their use as supercapacitors, proton and electron conductive materials. We continue to extend this chemistry to new frameworks and nanocrystals in which the pores are decorated by multiple functionalities arranged and apportioned in unique sequences throughout the material. We believe these regions and sequences code for specific properties in a way that is not too dissimilar from sequences of nucleotides in DNA and amino acids in proteins. Thus our work is aimed at making MOF, COF and ZIF materials capable of (a) counting and sorting molecules, (b) having compartments which are linked yet function synergistically, (c) carrying out multiple catalytic transformations in precisely controlled molecular space, and (d) exhibiting hybrid properties of molecular recognition, signal transduction and mechanical action.

Recently, we have succeeded in demonstrating the use of MOFs to harvest water from the desert air, as well as pioneered molecular weaving. We used coordination chemistry to bring together organic threads in a weaving manner. Once the structure is formed, it can be demetalated leaving behind a thoroughly woven organic ‘cloth’ for which the elastic properties are dramatically different than those of the metalaled forms. Molecularly woven chemical structures of this kind provide means of accessing frameworks that combine dynamics with resiliency. The principles of this new science are being extended to polymers and nanocrystals.

In the News

August 27, 2019

Water harvester makes it easy to quench your thirst in the desert

With water scarcity a growing problem worldwide, University of California, Berkeley, researchers are close to producing a microwave-sized water harvester that will allow you to pull all the water you need directly from the air — even in the hot, dry desert.
May 1, 2019

Eight Berkeley faculty elected to National Academy of Sciences

In recognition of their outstanding achievements in original research, eight UC Berkeley faculty have been elected members of the National Academy of Sciences, one of the most distinguished scientific organizations in the country. The newly elected researchers include a neuroscientist, two physicists, two cellular biologists, a computer scientist, a chemist and an economist, and bring the total number of living UC Berkeley faculty who are members of the academy to 135.

Featured in the Media

Please note: The views and opinions expressed in these articles do not necessarily reflect the official policies or positions of the campus.
August 29, 2019
A new version of a water harvester that can pull water from air, even in desert conditions, is 10 times better than an earlier version and is headed for market. A team of scientists led by chemistry professor Omar Yaghi developed the device, which uses a water-absorbing material called a metal-organic framework, or MOF, to reliably produce more than five cups, or 1.3 liters, of water per day per kilogram of MOF. That amount of water is more than required for one person to stay alive. "We are making ultra-pure water, which potentially can be made widely available without connection to the water grid," Professor Yaghi says. "This water mobility is not only critical to those suffering from water stress, but also makes possible the larger objective -- that water should be a human right." Professor Yaghi's startup, Water Harvester Inc., is testing and will soon begin marketing a harvester that can supply 7 to 10 liters of water a day -- enough for two to three adults. For more on this, see our press release at Berkeley News. Stories on this topic appeared in dozens of sources around the world, including Centre Daily Times and Technology Networks.