Physical Sciences/Engineering

Enabling supercomputer simulations of heterogeneous catalysts

20 September 2022

Zacros

Molecular simulations can provide insights and understanding into materials for diverse applications, for example in electronics, structural mechanics, or chemical technologies. An example is the development of catalysts, which are solid materials that accelerate chemical reactions without being consumed in the process. Catalysts are widely used in many applications, from fine iron in the synthesis of ammonia, to platinum catalytic converter in your vehicle exhaust system.

Today, molecular simulations to study solid catalysts are expensive and slow. Zacros is a software package developed by Dr Michail Stamatakis from the Department of Chemical Engineering at UCL, using computer simulation method, Kinetic Monte Carlo to more accurately and efficiently model molecular phenomena on the surfaces of solid catalysts.

The ’meso-scale’ challenge

Molecular simulation methods have offered a fundamental understanding that has aided the development of catalyst formulations. However, under certain conditions these materials exhibit behaviours that can no longer be understood at the molecular level. An example is the emergence of spiralling patterns in catalytic systems used in emission control technologies. Such patterns, with wavelengths on the order of micro-metres, have been experimentally observed in the oxidation of carbon monoxide (CO) on platinum surfaces [cf. J. Chem. Phys. 98, 9977 (1993); https://doi.org/10.1063/1.464323].

In studying such systems, researchers have resorted to rougher and more general macro-scale approaches to explain such phenomena, to the detriment of fidelity and predictive capability. It is also challenging to find ways to improve an existing catalytic material, engineer a novel and better one, or choose reaction conditions that optimise catalytic performance. Bridging the molecular and macroscopic scales for accurate simulation of materials is such a challenge known as the ‘meso-scale’.

Michail Stamatakis

Empowering researchers

Zacros is a software package developed by Dr Michail Stamatakis to simulate molecular phenomena on the surfaces of solid catalysts at the meso-scale. Zacros empowers researchers with advanced computational tools to help answer the pertinent questions and guide the design of catalytic materials towards more efficient chemical processes. The software has already been used to unravel the complexity of catalytic reactions in the industrial chemistry, energy and sustainability fields, for example in the context of vehicle emissions control technologies, biomass reforming, or natural gas conversion to fuels and chemicals.

Streamlined and effective licensing

Michail was looking for a streamlined and effective licensing platform that would make Zacros available to a large number of interested users in academia and industry. XIP, UCLB’s express licensing platform, was an ideal choice, providing a user-friendly and intuitive framework that made it easy to distribute Zacros to these user-groups. UCLB worked closely with Michail, and as of May 2022, Zacros has been licensed to about 570 users in more than 280 research groups in 56 countries, including some commercial R&D groups. Moreover, at least 38 external studies using Zacros have appeared in the literature (31 of which were published from 2019 onwards) conducted independently, without the supervision or involvement of Michail. This is a clear indication of successful technology transfer which would not be possible without the XIP licensing platform.

Zacros

Developing a platform

Together with Michail, UCLB is working on developing the Zacros software suite including graphical user interfaces for the creation of Zacros input files and the post-processing of simulation data. Zacros-post (also distributed on XIP) is a first deliverable of these efforts. The goal is to develop and make available a comprehensive and user-friendly kinetic modelling platform for materials modelling and beyond. Moreover, in collaboration with other academics and software developers in the context of European project, ReaxPro, Zacros is being linked with software packages that simulate reactive processes at lower scales – electronic and atomistic – as well as at higher ones – phenomenological / reactor scale. It is a challenging but exciting project that will deliver a framework with unprecedented predictive capabilities towards understanding catalysts at a fundamental level, and coming up with innovative, efficient, sustainable and economic designs of chemical processes.

“The Zacros modelling software has been widely distributed and I’m excited about how far it has come, and the impact it has delivered to many academic and commercial groups in the catalysis fields. There’s a lot more development in the pipeline so I’m looking forward to continuing to grow the Zacros suite of products.” – Nicholas Yiu, Business Manager, UCLB.

 

References

  1. https://www.ucl.ac.uk/chemical-engineering/news/2021/sep/virtual-time-and-graph-theory-stepping-catalytic-materials-simulations