Porous Liquids for Catalysis

Porous liquids (PLs) are an exciting new class of counterintuitive porous materials that combine the properties of a microporous solid with the mobility of a liquid. Like their solid counterparts, these liquids with holes have the capability to demonstrate gas uptake and release, and guest selectivity. However, unlike solid porous materials, they could also potentially have unique applications, such as the ability to be pumped around a continuous system facilitating guest loading/unloading steps, or being used as a gas-loaded reaction solvent. Despite this potential, the application of PLs in areas other than gas uptake and selectivity has not been investigated. Recently, we reported the formation of high cavity concentration PLs using porous organic cages (POCs) - discrete molecules containing permanent molecular cavities accessible through windows - and demonstrated their ability to exhibit increased uptake of a range of gases (e.g., CO2, CH4, Xe, SF6) over neat liquids (Nature, 2015, 527, 216; Chem. Sci., 2017, 8, 2640, ChemRxiv, 2021, DOI:10.26434/chemrxiv.14719503.v2). In addition, there have been reports of the use of solutions of cages for catalytic CO2 conversion into cyclic carbonates (Sustainable Energy Fuels, 2019, 3, 2567), and as nanoreactors (Chem. Soc. Rev., 2008, 37, 247). These systems differ from PLs, which are defined as having permanently empty pores that are accessible to guests, due to either guests being in competition with the solvent which occupies the cavities or guest binding being driven by a hydrophobic effect. In this project, we will build on these initial reports and explore different ways of applying PLs in the area of catalysis. This includes the use of gas-loaded PLs as a reusable and controllable external gas source in stoichiometric gas reactions, and as a solvent to carry out lower pressure gas reactions by 'simulating' high gas concentrations that are normally only achieved at higher pressures, and as nanoreactors to catalyse small molecule reactions by confinement. Once we have a thorough understanding of these different methodologies, we will then seek to translate this into a high-throughput workflow with the aim of being able to use PLs to rapidly screen a range of catalytic reactions involving the incorporation of a gas as a reagent.

Academic impact:
Recent advances in data science and digital technology have a disruptive effect on the way synthetic chemistry is practiced. Competence in computing and data analysis has become increasingly important in preparing chemistry students for careers in industry and academic research.

The CDT cohort will receive interdisciplinary training in an excellent research environment, supported by state-of-the-art bespoke facilities, in areas that are currently under-represented in UK Chemistry graduate programmes. The CDT assembles a team of 74 Academics across several disciplines (Chemistry, Chemical Engineering, Bioengineering, Maths and Computing, and pharmaceutical manufacturing sciences), further supported by 16 industrial stakeholders, to deliver the interdisciplinary training necessary to transform synthetic chemistry into a data-centric science, including: the latest developments in lab automation, the use of new reaction platforms, greater incorporation of in-situ analytics to build an understanding of the fundamental reaction pathways, as well as scaling-up for manufacturing.

All of the research data generated by the CDT will be captured (by the use of a common Electronic Lab Notebook) and made openly accessible after an embargo period. Over time, this will provide a valuable resource for the future development of synthetic chemistry.

Industrial and Economic Impact:
Synthetic chemistry is a critical scientific discipline that underpins the UK's manufacturing industry. The Chemicals and Pharmaceutical industries are projected to generate a demand for up to 77,000 graduate recruits between 2015-2025. As the manufacturing industry becomes more digitised (Industry 4.0), training needs to evolve to deliver a new generation of highly-skilled workers to protect the manufacturing sector in the UK. By expanding the traditional skill sets of a synthetic chemist, we will produce highly-qualified personnel who are more resilient to future challenges. This CDT will produce synthetic chemists with skills in automation and data-management skills that are highly prized by employers, which will maintain the UK's world-leading expertise and competitiveness and encourage inward investment.

This CDT will improve the job-readiness of our graduate students, by embedding industrial partners in our training programme, including the delivery of training material, lecture courses, case studies, and offers of industrial placements. Students will be able to exercise their broadened fundamental knowledge to a wide range of applied and industrial problems and enhance their job prospects.

Societal:
The World's population was estimated to be 7.4 billion in August 2016; the UN estimated that it will further increase to 11.2 billion in the year 2100. This population growth will inevitably place pressure on the world's finite natural resources. Novel molecules with improved effectiveness and safety will supersede current pharmaceuticals, agrochemicals, and fine chemicals used in the fabrication of new materials.

Recent news highlights the need for certain materials (such as plastics) to be manufactured and recycled in a sustainable manner, and yet their commercial viability of next-generation manufacturing processes will depend on their cost-effectiveness and the speed which they can be developed. The CDT graduates will act as ambassadors of the chemical science, engaging directly with the Learned Societies, local council, general public (including educational activities), as well as politicians and policymakers, to champion the importance of the chemical science in solving global challenges.