ANNUAL REPORT 2011 - University of Cape Town

ANNUAL REPORT
2011
M. Härting and D.T. Britton
October 2011

Contents
1. Introduction ......................................................................................................... 3
1.1 Members and Affiliates ....................................................................................... 3
2. An example of NanoSciences Innovation: Printed Silicon .............................. 4
3. Activities of the NanoSciences Innovation Centre .......................................... 6
3.1 Basic and Applied Research ............................................................................... 6
3.1.1 Research Highlights in 2011 ............................................................................. 6
3.1.2 Scientific Papers Published in 2011 .................................................................. 8
3.2 Technology Development ................................................................................... 8
3.2.1 Development Highlights in 2011 ....................................................................... 8
3.2.2 Products and applications demonstrated in 2011 ............................................. 9
3.3 Innovation ........................................................................................................... 10
3.3.1 Provisional patents filed in 2011 ..................................................................... 10
3.3.2 PCT patents filed in 2011 ............................................................................... 10
3.3.3 National Phase patents filed in 2011 .............................................................. 11
3.3.4 Patents granted in 2011 .................................................................................. 11
3.4 Capacity Building and networking ....................................................................... 11
3.4.1 Capacity building and networking highlights in 2011 ...................................... 11
3.4.2 Current Students and Fellows......................................................................... 12
3.4.3 Theses and Dissertations submitted in 2011 .................................................. 13
3.4.4 Degrees passed in 2011 ................................................................................. 13
4. Infrastructure and Capacity ............................................................................. 14
4.1 External Use of Infrastructure in 2011 .............................................................. 15
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1. INTRODUCTION
Recognising that innovation is an essential factor in turning cutting edge
nanoscience research into practical nanotechnology applications, the UCT
Nanosciences Innovation Centre was formally established in August 2010 as an
accredited research centre in the Department of Physics. The centre has a strong
focus on both basic research, with the generation of human resources and research
capacity, and on innovation through its IP generation and support of its own spin-out
companies. An example is its flagship project on the development of a printed silicon
technology.
The core values of the centre are: excellence in postgraduate education and
research in the nanosciences; leadership in innovation, and the commercialisation of
nanosciences to locally based nanotechnology oriented companies. The centre’s
primary function is to serve as an African hub for nanosciences research and
postgraduate education with an orientation towards renewable energy and
sustainable development. In the broader innovation landscape the other roles of the
centre are to continue to develop its existing technology platforms, generate new
intellectual property, and identify future applications.
1.1 MEMBERS AND AFFILIATES
Prof. David T. Britton, Dept of Physics, University of Cape Town, Director:
Capacity Building and Innovation
Prof. Margit Härting, Dept of Physics, University of Cape Town, Director:
Capacity Research and Development
Prof. M. Bluemnthal, Dept. of Physics
Dr. Schadrack Nsengiyumva, Dept of Physics, Rhodes University
Dr. Mira Topic, Materials Research Group, iThemba LABS
Dr. Manfred R. Scriba, National Centre for Nanostructured Materials, CSIR
Prof. Girma Goro Gonfa, Haramaya University, Ethiopia
Dr. Evariste Minani, Kigali Institute of Education, Rwanda
Prof. Gregory Beaucage, University of Cincinnati, USA
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1. AN EXAMPLE OF NANOSCIENCES INNOVATION:
PRINTED SILICON
Nanosciences innovation describes a holistic approach to all aspects of the
innovation chain, shown in figure 1. below, concentrating mainly on the progression
of an idea from basic research to proof of concept. In the case of printed silicon our
idea was simple: to print silicon nanoparticles on a substrate like paper to make
electronic devices. The road to commercialising a product based on this idea
required repeated review of the end goals in light of our research results and market
developments. Eight years later the first product was commercialised, and we had
developed our strategy of nanosciences innovation.
Figure 1. The links in the Innovation Chain, showing the areas of activity of the
NanoSciences Innovation Centre.
With formulating an ink from silicon nanoparticles and printing electronics in a similar
fashion to T-shirt printing, the printed silicon technology looks at first sight simple.
But behind this process, shown in figure 2 below, a whole groundwork of basic
science was needed to study and understand the properties of the materials. The
results of these studies informed the direction of the applied research into the
deposition of nanocomposite layers and the development of electronic devices,
which were in turn guided by the requirements of the chosen application. Above all
the final product was designed to make use of the unique and novel properties of the
material system.
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Figure 2: Printed silicon technology: from silicon particles to printed electronic devices and circuits
The key to the success of the technology lies in the quality of the surface of the
silicon particles, which are clean enough to let electric charge pass between
particles, but which are stable against oxidation. The second key, which opens up
doors to many other applications which cannot be achieved with electronics
technologies, is to understand and control the transport of electric charge through
the printed silicon. In the end it is the understanding of its unique transport properties
which allows printed silicon to be used, not only in sensor applications, but also in
photovoltaics and logic.
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3. ACTIVITIES OF THE NANOSCIENCES INNOVATION
CENTRE
Until now the main research and development activities of the NanoSciences
Innovation Centre were directed towards answering scientific questions related to the
properties of nanoparticles and physical processes on the nanoscale, and to develop
applications for its printed silicon technology. In continuing these tasks the centre is
also turning its attention to exciting new applications, including combining the printed
silicon technology with other nanomaterials, to develop for example robust solar cells
for lighting and communications in rural areas of Africa with no access to grid power.
As part of these activities the NanoSciences Innovation Centre is the primary hub of
the NanoPower Africa Network.
3.1 Basic and Applied Research
The core focus of our basic research is on the properties and interactions of
nanomaterials and nanostructured materials. We have a special emphasis on
nanoparticles and nanoparticulate composites of electronic materials, specifically
inorganic semiconductors like silicon. The goal is to understand the physical
processes which occur, not only in the synthesis and fabrication of the material, but
also in its application. A prime example of this is the generation and transport of
charge in the nanoparticle networks of printed silicon.
The main goal of our applied research is to build on our successes in printed
electronics to create an indigenous printable photovoltaic technology. This will
ultimately provide robust solar cells which will bring inexpensive energy to rural
areas of Africa which do not have access to grid power.
Another important activity is the development of new fabrication and characterisation
techniques, for which we have a well established long track record. Two important
new developments, which will improve the quality of both product development and
basic materials characterisation, are a novel synchrotron scattering technique to
study the connectivity of nanoparticulate networks and tomographic reconstruction of
nanoparticle structures from electron micrographs.
3.1.1 Research highlights in 2011
The most important basic knowledge gained, which built on research started prior to
the founding of the NanoSciences Innovation Centre, has been a comprehensive
understanding of the functioning of the printed silicon technology at the level of the
fundamental processes occurring at the interfaces between particles. This has three
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important aspects: firstly a study if the stable surface structure and composition of
silicon nanoparticles, secondly the factors influencing the hopping of charge carriers
between particles and clusters, and finally the mesoscale influence of the network
topology on the transport of charge.
Silicon particle surfaces have now been studied extensively with further HR-TEM
measurements (shown in figure 3), scanning near field optical microscopy and
confocal Raman spectroscopy to supplement earlier X-ray photoelectron
spectroscopy, confirming the reasons for the extraordinary surface stability. A
substantial manuscript is currently being prepared for submission to a major
interdisciplinary journal.
Figure 3: HR-TEM image of a silicon nanoparticle showing the internal grain structure and the clean
surface structure without a thick silicon dioxide layer.
A wealth of experimental data, for the investigation of charge transfer mechanisms in
nanoparticulate networks containing four different types of silicon nanoparticles, has
been obtained over an extended temperature range from 15K to 350K. Consistent
models for the hopping processes, and a description of the potential barriers,
between individual particles and between clusters of particles, have been developed.
This will form a major part of PhD thesis to be submitted early in 2012, and
subsequently written up in series of papers for publication.
In the framework of the NanoPower Africa project, in June 2012 members and
students of the NanoSciences Innovation Centre performed the first Ultra Small
angle X-ray scattering (USAXS) studies on this material system at the Advanced
Photon Source in Argonne National Laboratory and Small Angle Neutron Scattering
(SANS) studies at the High Flux Isotope Reactor (HFIR) at Oak Ridge National
Laboratory. The results from the USAXS studies are being used with collaborators at
the University of Cincinnati to jointly develop mathematical descriptions of the
topology of the particle network, and to validate a new experimental technique based
on the scattering nanometre wavelength radiation.
In collaboration with the UCT Electron Microscope Unit, established electron
tomographic methods have been further developed to apply them to reconstruct
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extended asymmetric structures, particularly irregular nanoparticles and polydisperse
clusters of particles. The outcomes of this applied research are now being used to
study basic features such as network topology, cluster morphology and particle
topography in nanostructured materials.
3.1.2 Scientific Papers published in 2011
Oxygen depth profiling in Kr + -implanted polycrystalline alpha titanium by means of
16 O(�,�) 16 O resonance scattering,
S. Nsengiyumva, J.P Rivière, A.T.Raji, C.M. Comrie, D.T. Britton, and M. Härting,
Journal of Nuclear Materials 414, 150 – 155 (2011).
Intrinsic defects and krypton impurity atoms in α-titanium: Ab initio density functional
study of diffusion and krypton-vacancy interactions,
A.T. Raji, R. Mazzarello, S. Scandolo, S. Nsengiyumva, M. Härting, D.T. Britton,
Physical Review B 83, 054120 (2011)
Electrically active, doped monocrystalline silicon nanoparticles produced by hot wire
thermal catalytic pyrolysis,
M. R. Scriba, D.T. Britton, and M. Härting
Thin Solid Films, 519, 4491 – 4494 (2011)
Defects in ion-implanted hcp-titanium: A first-principles study of electronic structures
A.T. Raji, R. Mazzarello, S. Scandolo, S. Nsengiyumva, M. Härting, and D.T. Britton
Solid State Communications, in press (2011)
3.2 Technology Development
Product and applications development in the NanoSciences Innovation Centre is
currently focussed on the use of the printed silicon technology. Much of this is in
collaboration with external partners, including PST Sensors, which is a spin-out from
the Centre. Besides actively prototyping sensors and active electronics components,
and manufacturing proof of concept demonstrators, we are independently developing
end-use applications for printed electronics, sensors and low power photovoltaics in
various industrial and social sectors. A final, important aspect is the scaling up and
industrialisation, also with external partners, of all the processes involved in the
printed electronics value chain.
3.2.1 Development Highlights in 2011
In 2011, in collaboration with PST Sensors the NanoSciences Innovation Centre has
made several notable advances in the temperature sensor technology, since the first
sensors (shown in figure 4 below) were exhibited at the 2011 Printed Electronics
Europe Conference in Dusseldorf, Germany in April 2011. At the conference and
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trade show, the NanoSciences Innovation Centre shared a booth with PST Sensors,
and exhibited its other printed electronics developments, including transitors and
passive components, as well as its research activities. The new developments,
including strain compensation, allowing the production of fully flexible, rollable and
even stretchable large area sensors, and sensor arrays for thermal mapping and
imaging will be exhibited ate the Printed Electronics Conference USA in Santa Clara
in December 2012.
Throughout the year, development of printable electronic materials has continued
with the successful production of graphitic nanoparticles which have been
incorporated in water based inks for printed electronics. Basic research on the
structure and properties of the graphitic nanoparticles is now ongoing and will
continue in 2012. Following on from these successes, the first approaches to printing
metallic nanoparticles, both as a replacement for conventional silver inks and to
study the properties of printed Schottky barriers, have yielded encouraging results.
Having demonstrated a working printed temperature sensor technology, the
NanoSciences Innovation Centre is leading a consortium involving members of
Groote Schuur Hospital and the department of Human Biology to develop sensors
for three specific medical applications. Preliminary results have shown that the
sensors can be successfully used to monitor different aspects of health and bodily
function, and ethical clearance is now being sought for a pilot study before
submitting a proposal for major funding.
3.2.2 Products and Applications demonstrated in 2011
First fully printed temperature sensor, shown in figure 3, Printed Electronics
Europe 2011, Dusseldorf, Germany in April 2011
Figure 4: Printed Silicon Temperature Sensor, developed by the UCT NanoSciences Innovation
Centre and commercialised by PST Sensors (pty) Ltd.
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Large area temperature sensor in form of life size hand graphic design, Printed
Electronics Europe 2011, Dusseldorf, Germany in April 2011
Temperature sensor arrays for thermal mapping, Printed Electronics USA 2012,
Santa Clara, 30th November – 1st December 2011
Strain compensated flexible temperature sensor, Printed Electronics USA 2012,
Santa Clara, 30th November – 1st December 2011
Temperature sensors, using inexpensive copper based inks as a replacement
for silver, Printed Electronics USA 2012, Santa Clara, 30th November – 1st
December 2011
3.3 Innovation
The NanoSciences Innovation Centre has a strong track record in Intellectual
Property generation, with 14 patent families filed . Of these, two patents have been
granted in the United States, two in Europe, and 3 in South Africa. Shortly after the
formal establishment of the Centre, the first South Africa second generation
nanotechnology company in the electronics sector, PST Sensors, was spun out.
Besides working with its own daughter company, The NanoSciences Innovation
Centre is engaging with other partners for commercial prototyping, leading to
licensing agreements for its intellectual property.
3.3.1 Provisional patents filed in 2011
A Method of Producing Nanoparticles
M.R Scriba and DT Britton
Flexible temperature and strain sensor
D.T. Britton and M. Härting
Large area temperature sensors
D.T. Britton and M. Härting
Printed semiconductor diodes,
M. Härting, D.T. Britton and U. Männl
3.3.2 PCT patents filed in 2011
Assembling and Packaging a Discrete Electronic Component
D.T. Britton and M Härting,
Printed Temperature Sensor
D.T. Britton and M Härting
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3.3.3 National Phase patents filed in 2011
Inkjet Printing of Nanoparticulate Functional Inks
M. Härting, D.T. Britton and E.A. Odo
Russia
Method of Producing Stable Oxygen Terminated Semiconducting Nanoparticles
D.T. Britton and M. Härting
Russia
3.3.4 International Patents granted in 2011
A Thin Film Semiconductor Device and Method of Manufacturing a Thin Film
Semiconductor Device,
M. Härting and D.T. Britton
US 8026565 USA
Doping of Particulate Semiconductor Materials
D.T. Britton and M. Härting
EP 1926843 European
Inkjet Printing of Nanoparticulate Functional Inks
M. Härting, D.T. Britton and E.A. Odo
EP 2285574 European
3.4 Capacity building and networking
As a university based research centre, our main contribution to human capacity
building is the training of Masters and Doctoral students at the cutting edge of
nanosciences research. Over the last 10 years we have graduated a total of 15 MSc
and 8 PhD students. However, with second focus on innovation and
commercialisation, there is excellent mentoring and opportunities for students who
make a more adventurous life choice – entrepreneurship. Additionally, as the primary
hub of an international capacity building network, NanoPower Africa, we are actively
involved in similar activities in four countries on the continent.
3.4.1 Capacity Building and Networking Highlights in 2011
The NanoPower Africa network was formally founded with the start of the USAID
funded project on 28 th February. However, its first activities commenced in the
second half of 2011 after all contractual issues between UCT and the US partner
institutions had been ironed out. The first significant activities were site visits by the
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coordinating team to the first two other African partner institutions in Rwanda and
Ethiopia. Key outcomes of these visits were the planning of research visits to Cape
Town and the USA by the senior members of the institutions, and the identification of
junior staff members who will join the NanoSciences Innovation Centre as
postgraduate students. Two junior staff members from each institution were
identified and have applied to UCT for first registration in 2012. Similarly, after the
first release of funds, recruitment of support and scientific staff, as well as local
postgraduate students for 2012 has been initiated in the second semester of 2011. In
total the postgraduate student cohort of the NanoSciences Innovation Centre is
expected to double from its mid-2011 number by April 2012.
This planned growth is enabled by the addition of new partners in the NanoPower
Africa network and the affiliation of locally based collaborators to the NanoSciences
Innovation Centre. Since its inception, new partners in at Rhodes University in South
Africa, and the University of Botswana and BOTEC in Gaberone, have joined the
NanoPower Africa Network. Within South Africa, the NanoSciences Innovation
Centre is consolidating its own network with affilates at other universities and
research institutions, including the CSIR National Centre for Nanostructured
Materials and iThemba LABS. Similarly, within the Department of Physics, associate
Professor Mark Blumenthal is the newest member of the NanoSciences Innovation
Centre.
As part of the USAID funded initiative, the members of the NanoSciences Innovation
Centre have been instrumental in implementing an experimental lecture series held
simultaneously at six sites, in four countries on two continents. The assistance of
UCT’s Health Science Faculty in providing essential infrastructure has been
invaluable in this regard. As part of this programme, African science and engineering
postgraduate students are expected to work with Amercian social and business
science undergraduate students, assisting them in understanding and developing
appropriate business models for solar power projects the different African countries.
As part of our involvement in USAID activities, a low key working visit by Dr. John. P.
Holdren, Director of the White House Office of Science and TechnologyPolicy, and
Assistant to the Preseident for Science and Technology, is planned for 11 th
November 2011.
3.4.2 Current Students and Fellows
MSc
David Moweme Unuigbe
Lehlohonolo Mongalo
Michel Mambouku Nzikou
Sara Abdelazeem Hassan Abass
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PhD
Lloyd Angelo Corker (under examination)
Emmanuel Ohieku Jonah
Batsirai Magunje
Stanley Douglas Walton
Stephen David Jones
Ulrich Männl
Post-doctoral
Abdulrafiu Tunde Raji
Rudolf Nüssl
3.4.3 Student Theses and Dissertations Submitted in 2011
Lloyd Angelo Corker, PhD
Lehlohonolo Mongalo, MSc
3.4.4 Degrees passed in 2011
Sara Abdelazeem Hassan Abass, MSc
Michel Nzikou, MSc
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4. INFRASTRUCTURE AND CAPACITY
The NanoSciences Innovation Centre is currently housed in the Physics Department
at the University of Cape Town, where the available space is not optimal for its
extensive equipment infrastructure. However, it is expected that more suitable
accommodation will become available in late 2012.
In-house equipment includes the following state of the art laboratory scale
characterisation facilities, as well as all the requirements of a well-found laboratory:
Spire Spi Cell AM1.5 solar cell tester (figure 5 left), Lake Shore 7700 cryogenic Hall
measurement system, Keithley 4200 semiconductor characterisation system, Wyko
NT9100 optical profiler (figure 5 right, a unique facility in Africa), and a Delta Nu
Advance 532 Raman spectrometer. Other in-house equipment includes printing and
deposition equipment, such as an Atma 60PD semi automatic screen printer, and
sample preparation facilities. Besides being used in house, the characterisation
facilities of the centre are regularly used by staff and students from all three local
universities and iThemba LABS.
Access to major equipment is provided through the University of Cape Town and
external collaborations, including the NanoPower Africa Network of which Oak Ridge
National Laboratory and Argonne National Laboratory are partners, which
guarantees access to synchrotron and neutron scattering experiments. High
resolution transmission and scanning electron microscopy is available on site in the
neighbouring UCT Electron Microsocope Unit.
Figure 5: State of the art equipment in the NanoSciences Innovation Centre: Spire SPI CELL solar cell tester
(left) and Wyko NT9100 Optical Profiler (right)
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4.1 External Use of Infrastructure in 2011
Wyko NT9100 profiler: Dept of Mechanical Engineering, UCT
iThemba LABS
University of the Western Cape
Raman Spectrometer: Dept. of Human Biology, UCT
University of the Western Cape
University of Stellenbosch
Lake Shore 7700 HMS: Dept of Mechanical Engineering, UCT
iThemba LABS
University of Stellenbosch
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