UK-China workshop on the chemistry and physics of functional materials

• Professor Henning Sirringhaus FRS, University of Cambridge, UK

Biography

Professor Henning Sirringhaus, FRS, is the Hitachi Professor of Electron Device Physics at the Cavendish Laboratory, University of Cambridge. He has been working in the field of charge transport and photophysics of organic semiconductors and physics of organic transistors since 1997. He has an undergraduate and PhD degree in physics from ETH Zürich (CH). From 1995-1996 he worked as a postdoctoral research fellow at Princeton University (USA) on α-Si TFTs for active-matrix liquid crystal displays. His current research interests include the realization of functional nanostructures using solution self-assembly, the charge and spin transport and photophysics of solution-processible organic, polymeric as well as oxide semiconductors and the development of printing-based manufacturing processes. He is a co-founder and Chief Scientist of Plastic Logic Ltd, a technology start-up company commercialising printed organic transistor and flexible display technology, and of Eight 19, a spin-off company commercialising organic solar cell technology.

• Professor Anthony Cheetham FRS, University of Cambridge, UK

Biography

Tony Cheetham obtained his DPhil at Oxford in 1971 and did post-doctoral work in the Materials Physics Division at Harwell. He joined the chemistry faculty at Oxford in 1974, and then moved to the University of California at Santa Barbara in 1991 to become Professor in the Materials Department. In 1992 he took up the Directorship of the new Materials Research Laboratory, which he led for the first 12 years of its existence. He became the Director of the new-created International Center for Materials Research at UCSB in 2004, and then moved to Cambridge in 2007 to become the Goldsmiths’ Professor of Materials Science. Cheetham is a Fellow of the Royal Society (1994), TWAS (1999), the German National Academy of Sciences (2011), and several other academies.

• Professor Wenping Hu, Chinese Academy of Sciences, China

Biography

Wenping Hu was born in China. Now he is a Professor of Institute of Chemistry, Chinese Academy of Sciences (ICCAS). He received his PhD degree from ICCAS in 1999, then, he worked in Osaka University as a research fellow of Japan Society for the Promotion of Sciences (1999-2001), in Stuttgart University as a research fellow of Alexander von Humboldt Foundation (2001-2003). In 2003, he joined in the Basic Research Laboratories, Nippon Telephone and Telegraph (NTT, Japan) and then returned to ICCAS. He is focusing on organic optoelectronics since 1996 and has published more than 240 refereed papers. He has edited “Organic Optoelectronics” for Wiley-VCH,“Organic Field-effect Transistors” for China Science Press, and co-edited “Molecular Materials and Thin Film Devices” for China Chemical Industry Press. He has been awarded as Distinguished Researcher of NTT (2005), the National Science Fund for Distinguished Young Scholars (2007), Excellent Instructor of Chinese Academy of Sciences (2007, 2008, 2009, 2011), Outstanding instructor of Ministry of Education (2009), Young Chemist Award of Chinese Chemical Society (CCS) and Royal Chemical Society (2010), and CCS-Evonik (Degussa) Chemical Innovation Award (2012) in recognition of his renowned research in the area of organic optoelectronic materials and devices.

• Professor Deqing Zhang, Chinese Academy of Sciences, China

Biography

Professor Deqing Zhang studied chemistry in Beijing Normal University from 1983 to 1987.He then joined in the Institute of Chemistry, Chinese Academy of Sciences (ICCAS) as a graduate student and obtained his MS. in Organic Chemistry in 1990. He conducted research on electron donor–acceptor cyclophenes at the Max-Planck Institute for Medical Research in Heidelberg (Germany) under the supervision of Professor Dr H A Staab, and received his Doctor degree (DR RER NAT) from Ruprecht-Karls University Heidelberg in 1996. He is now a research Professor in ICCAS. His research interests include development of external stimuli-responsive molecular systems for molecular switches, logic gates and chemical/bio-sensors. He also shows interests in design and synthesis of organic functional materials and organic nanoassemblies.He has published more than 130 papers in refereed journals. He serves as editorial advisory board member of several scientific journals including Adv Funct Mater, Dyes and Pigments, Polymer J.

• Professor Daoben Zhu, Institute of Chemistry, CAS, China
• Audio recording (mp3)

Biography not available

• Professor Yongfang Li, Institute of Chemistry, CAS, China
• Audio recording (mp3)

Biography

Yongfang Lihas been a Professor at Institute of Chemistry, Chinese Academy of Sciences (ICCAS) since 1993. He obtained his PhD in Physical Chemistry in 1986 from Fudan University and then worked as a postdoctoral fellow from 1986–1988 at ICCAS. He was a visiting scientist at the Institute for Molecular Science from 1988 to 1991 and in UCSB from 1997 to 1998. His present research interests are polymer solar cells (PSCs) and related photovoltaic materials, including conjugated polymer donor, solution processable organic molecule donor and soluble fullerene derivative acceptor. He has published one book, 12 book chapters and more than 400 peer-reviewed papers in the fields of photovoltaic materials and device of PSCs, semiconductor nanocrystals and the electrochemistry of conducting polymers. The published papers were cited by others for more than 8000 times.

Abstract

Polymer solar cells (PSCs) have attracted great attention in recent years, because of their advantages of low cost fabrication, light weight and possibility to be fabricated into flexible devices. The key issues are the design and synthesis of high efficiency conjugated polymer donor and fullerene derivative acceptor photovoltaic materials with broad absorption, higher charge carrier mobility (high hole mobility for the conjugated polymer donor and high electron mobility for the fullerene derivative acceptor) and suitable electronic energy levels (relatively lower HOMO energy level for polymer donor and relatively higher LUMO level for fullerene acceptor). In this presentation, I will talk about our recent progress on new conjugated polymer donor and new fullerene derivative acceptor photovoltaic materials.The conjugated polymer donor materials include new D-A copolymers, conjugated polymers with electron-withdrawing substituent, and 2D-conjugated polymers with conjugated side chains. The fullerene derivative acceptor materials include indene-C₆₀ bisadduct (ICBA) and indene-C₇₀ bisadduct (IC₇₀BA) etc.PCE of the PSCs based on our new donor and acceptor materials reached over 7%.

• Professor Sir Richard Friend FRS, University of Cambridge, UK
• Audio recording (mp3)

Biography

Richard Friend is the Cavendish Professor of Physics in the University of Cambridge.  He has developed the semiconductor physics of pi-conjugated organic polymers, and his research group has demonstrated that these materials can be used in wide range of semiconductor devices, including light-emitting diodes, solar cells and transistors.

Abstract

Excitons in molecular semiconductors generally show high Coulomb binding energies and exchange energies, of order 0.5 eV, because dielectric screening is low. These both present challenges and opportunities in both light-emitting diodes and also in solar cells.  Non-geminate electron-hole collisions produce 25% spin singlet events and 75% spin triplet events. For LEDs we observe both channels by probing transient absorption and electroluminescence.  We also find that the triplet excitons can decay efficiently through triplet-triplet fusion to produce an emissive singlet exciton.  Large exchange energies allow scope for multiple exciton generation for materials for which the triplet exciton energy is less than one half of the singlet exciton energy, since this favours energetically the fission of a photogenerated singlet to a pair of triplet excitons. If this process can be used in tandem with a lower energy gap semiconductor that harvests singlet excitons directly then this may enhance solar energy conversion beyond the single-junction Shockley-Queisser limit.  We have shown that this can be achieved using a pentacene/lead selenide hybrid solar cell device structure.

• Professor Alessandro Troisi, University of Warwick, UK
• Audio recording (mp3)

Biography

Alessandro Troisi received his PhD in Bologna (Italy) in 2002 working on charge transport in DNA.  After postdoctoral work at Northwhestern University (USA) and Bologna in 2005 he joined the faculty of the University of Warwick where, since 2010, he is professor of physical chemistry.  His interests include charge transport in organic materials (polymeric and molecular), electron transport through single molecules, microscopic modeling of solar cells and theory of self-assembly.  He is the recipient of the Marlow Medal of the Royal Society in 2007 and the ERC-Starting investigator award in 2009.

Abstract

The key process in organic photovoltaics cells is the separation of an exciton, close to the donor/acceptor interface into a free hole (in the donor) and a free electron (in the acceptor). In an efficient solar cell, the majority of absorbed photons generate such hole-electron pairs but it is not clear why such a charge separation process is so efficient in some blends (for example in the blend formed by poly(3-hexylthiophene) (P3HT) and a C60 derivative (PCBM)) and how can one design better OPV materials. In this talk a combination of atomistic model and phenomenological theories is presented and a rather different view of the charge separation process is proposed. A discussion on the actual role of computational and theoretical models in the development of organic electronics is presented and few examples of genuine material properties predictions based on computational models are given.

• Professor Matthew Rosseinsky FRS, University of Liverpool, UK
• Audio recording (mp3)

Biography

Matthew Rosseinsky obtained a degree in Chemistry from the University of Oxford and a D Phil under the supervision of Professor P Day, FRS in 1990. He was a Postdoctoral Member of Technical Staff at AT &T Bell Laboratories in Murray Hill, New Jersey where his work with D W Murphy, A F Hebard and R C Haddon led to the discovery of superconductivity in alkali metal fullerides. In 1992, he was appointed University Lecturer at the Inorganic Chemistry Laboratory, University of Oxford, where he remained until 1999 when he moved to the University of Liverpool as Professor of Inorganic Chemistry. He was awarded the inaugural de Gennes Prize for Materials Chemistry (a lifetime award for achievement in this research area open to all scientists internationally) by the Royal Society of Chemistry in 2009 and the CNR Rao Award of the Chemical Research Society of India in 2010. He was elected a Fellow of the Royal Society in 2008, and was awarded the Hughes Medal of the Royal Society in 2011.  His work addresses the synthesis of new functional materials for energy and information storage applications, and has been characterised by extensive collaboration with many academic and industrial colleagues.

Abstract

There are a range of challenges for the synthesis of new solid materials in the area of energy technologies, for example in solar fuel production and in efficient energy conversion devices such as fuel cells. This presentation will address new porous materials for photocatalytic generation of hydrogen (1), crystal chemical models for candidate highly conducting interfaces in thin films (2) and a method to identify candidate solid oxide fuel cell cathodes integrating computation and experiment.

(1) A Fateeva et al Angewandte Chemie Int Ed 2012 in press
(2) M Dyer et al Angewandte Chemie Int Ed 2012, 124, 3474

• Professor Gabriel Aeppli FRS, University College London, UK
• Audio recording (mp3)

Biography

Professor Aeppli is the Quain Professor of Physics and Director of the London Centre for Nanotechnology. Prior to taking up these posts in the autumn of 2002, he was a Senior Research Scientist for NEC (Princeton), a Distinguished Member of Technical Staff at Bell Laboratories, a Research Assistant at MIT, and an industrial co-op student at IBM. He obtained a BSc in Mathematics and PhD, MSc & BSc in Electrical Engineering from MIT. Honours include Membership of the American Academy of Arts and Sciences (2012), Fellowship of the Royal Society (2010), the IOP (Institute of Physics) Mott Prize (2008), APS (American Physical Society) Oliver Buckley Prize(2005), the Majumdar Memorial Award of the Indian Association for the Cultivation of Science(2005), the IUPAP Magnetism Prize/Neel Medal(2003), Riso National Laboratory Fellow(2002), Royal Society Wolfson Research Merit Award(2002), Fellow of the American Physical Society(1997), and Fellow of the Japan Society for the Promotion of Science(1996). In addition, he has been a member and chairman of many panels, sponsored by the USDOE, American Physical Society, EPSRC, and National Research Council (US), among others.

Aeppli’s experience and involvement with nanotechnology are both managerial and scientific. He co-founded the interdisciplinary and interuniversity (Imperial and University Colleges) London Centre for Nanotechnology (www.london-nano.com), developed its overall problem-solving strategy, arranged for the procurement of a new laboratory/office facility dedicated to nanotechnology in central London, defined the operating model in collaboration with colleagues at both Colleges, and is now managing operations and future programme development.

His personal research is currently focused on the implications of nanotechnology for information processing and health care. He is also a co-founder of Bio-Nano Consulting (BNC), a firm - spun out of the LCN and the IBE(Institute for Bio-Engineering at Imperial College) - which provides a range of services from due diligence to testing and prototyping in the nanotechnology arena.

Abstract

The concept of electronic inhomogeneity is central to the science and technology of transition metal oxides, including both the manganites as well as the high temperature superconductors. We describe recent scanning tunneling microscopy and X-ray experiments where we both characterize and control the responsible defects. In particular, we show the first direct images of oxygen adatom - vacancy pairs and their motion, including bistability and electric field induced switching - ultimately responsible for memristive action -  alongside their effects on the electronic density of states. Furthermore, we have used X-ray microscopy first to establish the extraordinary inhomogeneity, due to ordered oxygen defect domains, of an “optimally” prepared high temperature superconductor, and then as a lithographic tool to “write” superconducting wires.

• Professor Clare Grey FRS, University of Cambridge, UK and Stony Brook University, USA
• Audio recording (mp3)

Biography

Clare P Grey is the Geoffrey Moorhouse-Gibson Professor of Chemistry at Cambridge University.  She received a BA and DPhil (1991) in Chemistry from the University of Oxford.  After spending two years as a visiting scientist at DuPont CR&D in Wilmington, DE (1992–1993) she joined the faculty at Stony Brook University (SBU) as an Assistant (1994), Associate (1997) and then Full Professor (2001).  Since moving to Cambridge in 2009, she still maintains a part-time position at SBU, where she is the Associate Director of the Northeastern Chemical Energy Storage Center, a Department of Energy, Energy Frontier Research Center.  Her recent honors and awards include the 2007 Research Award of the Battery Division of the Electrochemical Chemical Society, the 2010 Ampere and RSC John Jeyes Awards, the 2011 Royal Society Kavli Lecture and Medal for work relating to the Environment/Energy and an Honorary PhD Degree “Docteur Honaris Causa” from the University of Orleans (2012).  She was elected to the Royal Society in 2011.  Her research interests include the use of solid state NMR and diffraction methods to investigate structure and dynamics in materials for energy storage and conversion and in environmental chemistry. 

Abstract

A full understanding of the operation of a battery, battery and fuel cell requires that we utilize methods that allow devices or materials to be probed while they are operating (i.e., in-situ). This allows, for example, the transformations of the various cell components to be followed under realistic conditions without having to disassemble and take apart the cell.  To this end, the application of new in and ex-situ Nuclear Magnetic Resonance (NMR) and magnetic resonance imaging (MRI) approaches to correlate structure and dynamics with function in lithium-ion and lithium air batteries, fuel cells membranes and supercapacitors will be described. The in-situ approach allows processes to be captured, which are very difficult to detect directly by ex-situ methods.  For example, we can detect side reactions involving the electrolyte and the electrode materials, sorption processes at the electrolyte-electrode interface, and processes that occur during extremely fast charging and discharging. Ex-situ NMR investigations allow more detailed structural studies to be performed to correlate local and long-range structure with performance in both batteries and fuel cell materials.

In this talk, I will describe the use of NMR spectroscopy to probe local structure changes in lithium ion batteries focusing on our work with the anode material Si, on lithium air cathodes, and to investigate Li dendrite formation in lithium metal batteries.  Finally, the application of NMR to examine double layer formation in electrolytic double layer capacitors (supercapacitors) will be described. 

• Professor Yunqi Liu, Chinese Academy of Sciences, China
• Audio recording (mp3)

Biography

Yunqi Liu graduated from the Department of Chemistry, Nanjing University in 1975, and received a doctorate from the Tokyo Institute of Technology, Japan in 1991. Presently, he is a Professor in the Institute of Chemistry, Chinese Academy of Sciences, China. His research interests include synthesis of molecular materials including p-conjugated small molecules/polymers, carbon nanotubes and graphenes, fabrication of related devices including light-emitting diodes, field-effect transistors and molecular electronics, and investigation of their electronic properties.

Abstract

Graphene has attracted significant attention in recent years. In additional to the mechanical cleavage of graphite, many methods have been developed to prepare graphene. Among them, chemical vapor deposition (CVD) opens a possibility for a wide range of applications of graphene in electronics. Graphene films with monolayer or few-layer coverage have been synthesized on many metals, e.g. Ni, Cu, Fe and Co, via a CVD process. However the complicated transfer techniques for metal-catalyzed graphene or the high cost of the single crystal SiC substrates limit the wide application of these graphene in nanoelectronics.

In this presentation [1 7], we used a modified CVD approach to produce high quality graphene by using solid Cu and liquid Cu as catalysts, or directly on dielectric subutrates. Moreover, we will also report the synthesis of highly N-doped tetragonal-shaped single crystal graphene arrays. In addition, the electronic devices based on these graphenes were fabricated and investigated.

References:

1. Lei Zhang, et al, Adv Mater, 2012, 24, 436.
2. Yugeng Wen, et al, Adv Mater, 2012, 24, 1471.
3. Dechao Geng, et al, Proc Natl Acad Sci, 2012, 109, 7992.
4. Yugeng Wen, et al, Adv Mater, 2012, 24, 3482.
5. Yunzhou Xue, et al, J Am Chem Soc, 2012, 134, 11060.
6. Jian Zheng, et al, Sci Rep, 2012, 2, 662.
7. Dacheng Wei, et al, Acc Chem Res, DOI: 10.1021/ar300103f.

• Professor Hong-Jun Gao, Institute of Physics, CAS, China
• Audio recording (mp3)

Biography

Dr Hong-Jun Gao got his PhD at Peking University in 1994 and is now a Professor and Deputy-Director of the Institute of Physics, Chinese Academy of Sciences. He is the Academician of the Chinese Academy of Sciences and the Academician of the Developing Country Academy of Sciences.  He is a Fellow of the Institute of Physics, UK, and has served as an Associate Editor for Appl Phys Lett since 2010 and an editorial board member for the New Journal of Physics since 2003.  He was the Scientific Secretary of the International Union of Vacuum Science, Technology, and Applications (IUVSTA) in the triennium 2004-2007, and is now the Chairman of the Nano-science Division, IUVSTA.  From 1997 to 2000, he worked at the Oak Ridge National Laboratory (ORNL) as a Guest Scientist. His research interests are in scanning tunneling microscopy/spectroscopy (STM/STS) and surface/interface structure and physical properties with including molecules at solid surfaces at a single molecular level. He has 6 international books/chapters and about 300 journal publications including 6 international invited review articles and 17 PRL, 7 JACS, and 10 Adv Mater papers. He was awarded the “OCPA AAA (Robert) Prize” (OCPA: the Overseas Chinese Physics Association; AAA: Achievement in Asia Award), the “TWAS Prize in Physics 2009” (TWAS: Third World Academy of Sciences), and “Humboldt Research Award 2010”.

Abstract

Graphene (G) is considered as a serious contender for being the reference material for a post-CMOS technology. Nevertheless, the use of graphene for applications requires mass production of high quality material and also its transfer to insulating substrates. While epitaxial growth in SiC and CVD growth in metal surfaces have seen enormous progress, transfer techniques are still a major challenge and a limiting factor of the material quality. I will present a new strategy for graphene growth on metallic Ru(0001) followed by silicon-layer intercalation that not only weakens the interaction of graphene with the metal substrate but also retains its superlative properties. This G/Si/Ru architecture, produced by silicon-layer intercalation approach (SIA), was characterized by Raman spectroscopy, scanning tunnelling microscopy/spectroscopy, and angle resolved electron photoemission spectroscopy. The SIA eliminates the need for the graphene transfer and also allows for an atomic control of the distance between the graphene and the metal gate, opening doors for a new generation of graphene-based materials with tailored properties.

References:

1. Y. Pan et al, Chinese Physics 16, 3151 (2007).
2. Y. Pan et al, Adv Mater 21, 2777 (2009).
3. J.H. Mao et al, Appl Phys Lett 100, 093101 (2012) (Cover story).

In collaboration with Yi Pan, Jinhai Mao, Li Huang, Junfeng He, Min Gao, Lizhi Zhang, Lida Pan, Haitao Zhou, Haiming Guo, Yuan Tian, Qiang Zou, Haigang Zhang, Yeliang Wang, Shixuan Du, Xingjiang Zhou, Institute of Physics, Chinese Academy of Sciences,  China; and Antonio H. Castro Neto, National University of Singapore, Singapore

• Professor Vladimir Falko, Lancaster University, UK
• Audio recording (mp3)

Biography and abstract not available

• Professor Zhigang Shuai, Tsinghua University, China
• Audio recording (mp3)

Biography

Zhigang Shuai gained his PhD in 1989 from Fudan University, Shanghai. From 1990-2001, he was postdoc and research associate with Professor Jean-Luc Brédas in the University of Mons, Belgium; from 2002-2008, “Hundre-Talent” professor at the Institute of Chemistry of the Chinese Academy of Sciences in Beijing; and 2008-present, Changjiang Scholar Chair professor, Tsinghua University, Beijing. His research interests are theoretical modeling of the organic functional materials for the opto-electronic properties. 260 publications with h-index= 44. Outstanding Young Investigator’s Fund (2004) and Chinese Chemical Society-AkzoNobel Chemical Sciences Award (2012). Member of the International Academy of Quantum Molecular Science, the Academia Europaea, and Fellow of the Royal Society of Chemistry. He is Associate Editor-in-Chief of “Acta Chimica Sinica” and “Frontiers of Chemistry in China”.

Abstract

Electron-phonon couplings (EPC) govern the optoelectronics performances for organic functional materials. Strong EPC causes charge localization. Localized charge can couple with intramolecular vibration, causing quantum effect on charge reorganization process, correcting the Marcus charge transfer rate formula and causing decreasing temperature behavior for the carrier mobility [1]. Molecular excited state is coupled with molecular vibration, and internal conversion occurs, dissipating electronic energy non-radiatively. We recently developed a combined non-adiabatic and spin-orbit couplings approach to evaluate the white organic light-emitting spectrum and quantum efficiency [2]. EPC are also the key for understanding and evaluating the charge distribution relaxation in the Boltzmann transport theory for the thermoelectric properties [3].

[1] H Geng et al, Adv Mater 2012, 24, 3568.
[2] Q Peng et al, J Chem Theory Comput, (accepted).
[3] D Wang, et al, PCCP 2012, 14, 16505.

• Professor Ullrich Steiner, University of Cambridge, UK
• Audio recording (mp3)

Biography

Ullrich Steiner is the Humphrey Plummer Professor of Physics of Materials. He received his undergraduate and PhD degrees in physics from Konstanz University (Germany). After research fellowships at the Weizmann Institute (Israel), the Institute Charles Sadron, Strasbourg (France), and University of Konstanz, he was the Professor of Polymer Chemistry at the University of Groningen (Netherlands) from 1999 – 2004.

Abstract

The performance of many multi-component materials depends sensitively on their detailed morphology.  Structure control on the 10-nm length scale is thought to approach the physical limit of this optimisation procedure.  For example, materials for photovoltaics, batteries, supercapacitors, and fuel cells rely on the detailed assembly of several components. Essential for these applications is not only the maximisation of the surface-to-volume ratio but also the inter-connectivity of the constituent phases.  Random assemblies of nanoscopic building blocks, while excelling in the first property, offer very little control over the detailed structure formation on the 10-nm length scale. Organic self-assmbly, on the other hand excels in the structural control on the 10-nm length scale, but is limited to organic materials.  Here, we employ polymer-self-assmbly to construct inorganic material assemblies, with the aim of optimising electronic and optical functionalities for a variety of applications.

• Professor Richard Catlow FRS, University College London, UK
• Audio recording (mp3)

Biography

Professor Richard Catlow has worked for over thirty years in the field of computational and experimental studies of complex inorganic materials.  His group has pioneered a wide range of applications of computational techniques in solid state chemistry to systems and problems including microporous and oxide catalysts, ionic conductors, electronic ceramics and silicate minerals.  This applications programme has been supported by technique and code development, including recent work on embedded cluster methodologies for application to the study of catalytic reactions.  The computational work has been firmly linked with experimental studies, using both neutron scattering and synchrotron radiation techniques, where the Royal Institute group has also made notable contributions to development as well as application studies.  Professor Catlow's research has led to over 800 publications, and in 2004 he was elected to Fellowship of the Royal Society.  He is currently Dean of the Mathematical and Physical Sciences Faculty at University College London.

Abstract

Computational techniques can be applied in an increasingly predictive manner to a wide range of structural and electronic properties of functional materials. This talk will summarise recent applications to:

(i) Modelling of the electronic structures of both rutile and anatase in the context of applications in solar energy devices
(ii) Modelling of the effects of disorder on the electronic properties of topological insulators
(iii) Predictions of the limits to doping in II/VI and III/V semiconductors
(iv) Modelling of reaction mechanisms for oxide and microporous catalytic systems

• Professor Peter Beton, University of Nottingham, UK
• Audio recording (mp3)

Biography

Peter Beton joined the University of Nottingham in 1988 as a postdoc and, following a period as a Royal Society University Research Fellow, was appointed to the academic staff in 1994. Following a period when he investigated quantum phenomena in electrical transport observed in semiconductor nanostructures fabricated using electron beam lithography, he set up a new programme on scanning probes. His research interests now lie at the intersection between materials science, physics, chemistry and device technology and his recent work has been focussed on supramolecular templates, random tiling, two-dimensional covalent networks, the growth of metal-organic frameworks and the deposition of polymers and polymer nanorings on metal surfaces.

Abstract

The properties of an entropy-stabilised supramolecular network will be reviewed. These networks map directly onto a rhombus tiling of the plane and support a random tiling phase which has been studied widely by theorists over several decades. The networks are treated them as projections of the (111) surface of a simple cubic crystal and are characterized using the height correlations of this virtual surface. It is also shown that topological defects are supported within this array and that broken symmetries lead to phase transitions between ordered and disordered phases. Growth of the networks, which are dynamically-arrested systems, will also be considered. The role of disorder in the formation of covalently bound molecular networks will also be presented, including a discussion of the influence of precursor flexibility on domain size and percolation pathways. In addition recent results on porphyrin polymers and nanorings deposited using electrospray will be presented. For these systems it is possible to define a 2D correlation length and we also discuss distortion, packing and stacking of flexible cyclic polymers.

^†Work performed in collaboration with Matthew Blunt, Andrew Stannard, Maria Wieland, James Russell, Juan Garrahan, Neil Champness, Simon Svatek, Luis Perdigao, Alex Saywell, James O’Shea, Johannes Sprafke, Dima Kondratiuk, Harry Anderson.