Report
Teaser, summary, work performed and final results
Periodic Reporting for period 2 - MaGic (The Materials Genome in Action)
Teaser
It is now possible to make an enormous spectrum of different, novel nanoporous materials simply by changing the building blocks in the synthesis of Metal Organic Frameworks (MOF) or related materials. This unique chemical tunability allows us to tailor-make materials that are...
Summary
It is now possible to make an enormous spectrum of different, novel nanoporous materials simply by changing the building blocks in the synthesis of Metal Organic Frameworks (MOF) or related materials. This unique chemical tunability allows us to tailor-make materials that are optimal for a given application. The promise of finding just the right material seems remote however: because of practical limitations we can only ever synthesize, characterize, and test a tiny fraction of all possible materials. To take full advantage of this development, therefore, we need to develop alternative techniques, collectively referred to as Materials Genomics, to rapidly screen large numbers of materials and obtain fundamental insights into the chemical nature of the ideal material for a given application.
Our ERC team tackles the challenge and promise posed by this unprecedented chemical tunability through the development of a multi-scale computational approach, which aims to reliably predict the performance of novel materials before synthesis. The team is developing methodologies to generate libraries of representative sets of synthesizable hypothetical materials and perform large-scale screening of these libraries. These studies should give us fundamental insights into the common molecular features of the top-performing materials. The methods developed will be combined into an open access infrastructure in which our hypothetical materials are publicly accessible for data mining and big-data analysis.
The project is organized in three Work Packages:
(1) Screen materials for gas separations and develop the tools to predict the best materials for carbon capture. In this Work Package the objective is to develop different computational tools to efficiently generate materials in silico and predict their properties.
(2) Gain insights into and develop a computational methodology for screening the mechanical properties of nanoporous materials. Often MOFs are not sufficiently stable against mechanical forces. The objective of this work package is to develop the tools to efficiently compute the mechanical properties and to use these tools to obtain a molecular understanding of what makes a MOF mechanically stable.
(3) Achieve a detailed molecular understanding of the performance of some MOFs. The objective of this work package is to obtain a detailed molecular understanding of the behaviour of MOFs that cannot be explained with the conventional methods
The overall objective is to combine the methods and expertise developed in these work packages to predict novel materials to efficiently capture carbon.
Work performed
We have focused on developing methodologies to predict in silico different materials. We have generated a library of MOFs with the MOF-74 topology. These materials are of practical interest because of they contain open metal sites. Of particular importance was that subsequently one of the predicted structures was successfully synthesized and the predicted adsorption isotherms of this material were in excellent agreement with the experimental one. We also generated a library of covalent organic frameworks (COFS), a library of schwarzites as can be obtained from zeolite templating, and a library of 2-D zeolite materials. In the future these materials will be screened for different applications (methane storage and different gas separations).
The method developments were focused on how to quantify similarity between pore shapes. At present the most reliable method is inspection by eye, but with thousands of materials this is not feasible anymore, we develop a methodology using applied topology to quantify the similarity between pores. A surprising problem in the databases of MOF crystal structures is that there are many duplicates, which the conventional techniques are not able to detect. We developed a procedure to detect these duplicates. We also have developed an improved algorithm to compute the pore volume of these materials. For some particular systems the conventional method gave incorrect results.
In addition, significant progress has been made on understanding the mechanical properties of MOFs. As a first step we tested the accuracy of force fields to predict mechanical properties. Once we established that these force fields were sufficiently accurate, we used them in a systematic study on how the MOF topology and functionalization contribute to the mechanical stability of the materials. This work gave us a simple recipe to predict whether functionalization of the MOF would lead to a stronger material.
We also wrote a review on the applications of the nanoporous materials genome for Nature Materials Review. And we gave the opening presentation of a Faraday Discussion on Carbon Capture giving a perspective of the different presentations that were given in these discussions.
Final results
The development of the methodologies allows us to carry out some detailed screening studies for novel materials to capture CO2. For this screening we will focus on wet flue gasses, which is a challenging separation, as water and CO2 often compete for the same adsorption site.