Liquid exfoliation is a simple and scalable approach for converting layered materials into free-standing single- and few-layer nanosheets with high aspect ratios. Early studies focussed on inorganic two-dimensional materials such as graphene but more recent examples have shown this approach can be adapted to exfoliate supramolecular structures. The high surface area, aspect ratios, and nanoscopic dimensions of these supramolecular nanosheets combined with their diverse and tunable chemistry make them ideal for a wide range of catalytic, sensing, electronics and separation applications.1 However, despite intensive research into these materials, the formation of monolayer nanosheets with high aspect ratios in good yields remains a challenge.
In our work, we have developed a library of metal-organic framework nanosheets (MONs) based on the metal-paddlewheel secondary building unit (Figure 1a). By synthesising isoreticular series of layered frameworks incorporating dicarboxylate linkers with different functional groups we have sought to understand the design principles behind nanosheet formation.2-4 We have also post-synthetically functionalised the frameworks with different functional groups to enhance exfoliation and add new properties.5-6 We are working with academic and industrial collaborators to develop MONs for a wide range of applications including sensors4,6,9 multistep catalysis,5 solar cells7,8 and composite materials applications.
We also recently utilised liquid exfoliation to access monolayer hydrogen-bonded organic nanosheets (HONs) with micron-sized lateral dimensions (Figure 1b).7 These HONs show remarkable stability and maintain their extended crystallinity and monolayer structures even after being boiled in water.
References
1. J. Nicks, K. Sasitharan, R. R. R. Prasad, D. J. Ashworth, J. A. Foster, Adv. Funct. Mater. 2021, 31, 2103723
2. D. J. Ashworth, A. Cooper, M. Trueman, R. W. M. Al-Saedi, L. D. Smith, A. J. H. M. Meijer and J. A. Foster, Chem.- A Eur. J., 2018, 24, 17986–17996.
3. D. J. Ashworth, T. M. Roseveare, A. Schneemann, M. Flint, I. D. Bernáldes, P. Vervoorts, R. A. Fischer, L. Brammer and J. A. Foster, Inorg. Chem., 2019, 58, 10837–10845.
4. D. J. Ashworth and J. A. Foster, Nanoscale, 2020, 12, 7986–7994.
5. J. Nicks, J. Zhang and J. A. Foster, Chem. Commun., 2019, 55, 8788-8791.
6. J. Nicks, J. A. Foster, Nanoscale, 2022,14, 6220-6227
7. K. Sasitharan, D. G. Bossanyi, N. Vaenas, A. J. Parnell, J. Clark, A. Iraqi, D. G. Lidzey and J. A. Foster, J. Mater. Chem. A, 2020, 8, 6067–6075.
8. K. Sasitharan, E.LK Spooner, R. C Kilbride J. Clark, A. Iraqi, D. G. Lidzey and J. A. Foster, Adv. Sci., 2022, DOI:10.1002/advs.202200366
9. J. Nicks, S. A. Boer, N. G. White and J. A. Foster, Chem. Sci., 2021,12, 3322-3327
Jonathan Foster completed his PhD at the University of Durham in 2008 in the groups of Prof. Jonathan Steed and Prof. Judith Howard FRS. In 2012 he moved to the University of Cambridge where he held post-doctoral positions in the groups of Prof. Jonathan Nitschke and Prof. Anthony Cheetham FRS. Jonathan joined the University of Sheffield in 2015 following the award of a Ramsay Fellowship and Sheffield Vice Chancellors Fellowship and was promoted to Lecturer in 2019 and Senior Lecturer in 2023.
Dr Foster's research interests lie at the interface between supramolecular chemistry and nanomaterials, understanding how to design simple molecules which can self-assemble to create nanostructured materials with sophisticated structures and properties. His current research is focussed on developing new classes of graphene-like nano-materials from supramoelcular materials such as metal-organic nanosheets (MONs) and hydrogen-bonded organic nanosheets (HONs). He works with a wide range of academic and industrial partners to develop their use for applications as diverse as solar cells, water purification, catalysis and biomedical sensing.
Liquid exfoliation is a simple and scalable approach for converting layered materials into free-standing single- and few-layer nanosheets with high aspect ratios. Early studies focussed on inorganic two-dimensional materials such as graphene but more recent examples have shown this approach can be adapted to exfoliate supramolecular structures. The high surface area, aspect ratios, and nanoscopic dimensions of these supramolecular nanosheets combined with their diverse and tunable chemistry make them ideal for a wide range of catalytic, sensing, electronics and separation applications.1 However, despite intensive research into these materials, the formation of monolayer nanosheets with high aspect ratios in good yields remains a challenge.
In our work, we have developed a library of metal-organic framework nanosheets (MONs) based on the metal-paddlewheel secondary building unit (Figure 1a). By synthesising isoreticular series of layered frameworks incorporating dicarboxylate linkers with different functional groups we have sought to understand the design principles behind nanosheet formation.2-4 We have also post-synthetically functionalised the frameworks with different functional groups to enhance exfoliation and add new properties.5-6 We are working with academic and industrial collaborators to develop MONs for a wide range of applications including sensors4,6,9 multistep catalysis,5 solar cells7,8 and composite materials applications.
We also recently utilised liquid exfoliation to access monolayer hydrogen-bonded organic nanosheets (HONs) with micron-sized lateral dimensions (Figure 1b).7 These HONs show remarkable stability and maintain their extended crystallinity and monolayer structures even after being boiled in water.
References
1. J. Nicks, K. Sasitharan, R. R. R. Prasad, D. J. Ashworth, J. A. Foster, Adv. Funct. Mater. 2021, 31, 2103723
2. D. J. Ashworth, A. Cooper, M. Trueman, R. W. M. Al-Saedi, L. D. Smith, A. J. H. M. Meijer and J. A. Foster, Chem.- A Eur. J., 2018, 24, 17986–17996.
3. D. J. Ashworth, T. M. Roseveare, A. Schneemann, M. Flint, I. D. Bernáldes, P. Vervoorts, R. A. Fischer, L. Brammer and J. A. Foster, Inorg. Chem., 2019, 58, 10837–10845.
4. D. J. Ashworth and J. A. Foster, Nanoscale, 2020, 12, 7986–7994.
5. J. Nicks, J. Zhang and J. A. Foster, Chem. Commun., 2019, 55, 8788-8791.
6. J. Nicks, J. A. Foster, Nanoscale, 2022,14, 6220-6227
7. K. Sasitharan, D. G. Bossanyi, N. Vaenas, A. J. Parnell, J. Clark, A. Iraqi, D. G. Lidzey and J. A. Foster, J. Mater. Chem. A, 2020, 8, 6067–6075.
8. K. Sasitharan, E.LK Spooner, R. C Kilbride J. Clark, A. Iraqi, D. G. Lidzey and J. A. Foster, Adv. Sci., 2022, DOI:10.1002/advs.202200366
9. J. Nicks, S. A. Boer, N. G. White and J. A. Foster, Chem. Sci., 2021,12, 3322-3327
Jonathan Foster completed his PhD at the University of Durham in 2008 in the groups of Prof. Jonathan Steed and Prof. Judith Howard FRS. In 2012 he moved to the University of Cambridge where he held post-doctoral positions in the groups of Prof. Jonathan Nitschke and Prof. Anthony Cheetham FRS. Jonathan joined the University of Sheffield in 2015 following the award of a Ramsay Fellowship and Sheffield Vice Chancellors Fellowship and was promoted to Lecturer in 2019 and Senior Lecturer in 2023.
Dr Foster's research interests lie at the interface between supramolecular chemistry and nanomaterials, understanding how to design simple molecules which can self-assemble to create nanostructured materials with sophisticated structures and properties. His current research is focussed on developing new classes of graphene-like nano-materials from supramoelcular materials such as metal-organic nanosheets (MONs) and hydrogen-bonded organic nanosheets (HONs). He works with a wide range of academic and industrial partners to develop their use for applications as diverse as solar cells, water purification, catalysis and biomedical sensing.
