Associate Professor Nunzio Motta

Broad area of research: Smart Systems

Prof. Motta was the first scientist in Italy to achieve atomic resolution by Scanning Tunneling Microscopy in 1991.

Main areas of research

• Nanotechnology
• Semiconductors
• Nanotubes
• Gas Sensors
• Solar cells

Nanotechnology
Nanotechnology aims at exploiting the remarkable size effects that arise when materials are reduced to nanoscale dimensions. Exploiting such effects will lead to new applications in different areas of human endeavor. 
Professor Nunzio Motta is an expert in the use of Scanning Tunneling Microscopy, Atomic Force Microscopy and Focused Ion Beam. These instruments allow the visualization and manipulation of objects on surfaces at the atomic and molecular level. His main focus is on achieving perfect ordering in the growth of nanostructures through nanopatterning.
The long-term goal of his research is to control the self-assembly of nanostructures by surface modification and patterning. This can be achieved in various ways: self-organization of surface structures, STM and Focused Ion Beam patterning
The new Focused Ion Beam (FIB) machine recently installed at QUT in the Australian Microscopy and Microanalysis Research Facility (AMMRF) linked laboratory is actively used to produce nanopatterned substrates in several research project. This machine will be complemented by a new Ultra High Vacuum Scanning Probe Microscopy facility, recently funded by the ARC.

Research projects

Semiconductor quantum dots
The race to increase the number of active components in a chip is leading the electronic industry to face the limits of top-down approach. Nanotechnology is creating the basis for a bottom-up approach, starting from atoms as building blocks of nanostructures.

The self assembly of three-dimensional islands is one of the most promising paths towards the fabrication of artificial atoms, or quantum dots (QDs), which are the promise for the future of memories and transistors.

We are studying the formation Ge dots occurring during layer by layer growth on nanopatterned Si substrates. We have been able to obtain a good control of the island by tuning the growth rate and the substrate temperature and using a combination of self-organization and Focused Ion Beam patterning (FIB). More recently growths on Si nanoindented substrates have been realized.

Collaborations: University of Roma Tor Vergata (Italy), ANU (Canberra).

Reference: Applied Physics Letters, 93(3). 031917. (2008)

Metal-free synthesis of carbon nanotubes
Controlled synthesis of carbon nanotubes (CNTs) is highly desirable for nanoelectronics applications. To date, metallic catalyst particles have been deemed unavoidable for the nucleation and growth of any kind of CNTs. However, the presence of metal species mixed with the CNTs represents a shortcoming for most electronic applications as metal impurities are incompatible with silicon semiconductor technology.

We are developing a metal-catalyst-free synthesis of CNTs, obtained through Ge nano-particles on a Si(001) surface. By using acetylene as the carbon feed gas in a low-pressure Chemical Vapor Deposition (CVD) system, multi-walled carbon nanotubes (MWNT) have been observed to grow from the smallest Ge islands.
Collaborations: ANU (Canberra), NAST centre University of Roma Tor Vergata (Italy).

Solar Powered Nano-Sensors
This project aims to the production of a new class of sensors for data collection in remote areas, by using integrated nanomaterials powered by state of the art Dye Sensitized Solar Cells. The sensors will be devoted to the detection of gases in three main backgrounds: ammonia (NH3) from cattle manure; nitrous oxide (N2O) from fertilizers; nitrogen dioxide from pollution or gas emissions from engines. The technology advance rendered by this project will enable improved monitoring of the environment in remote areas, especially in mining and agricultural contexts, leading to industrial and ecological benefits.

We are growing nanowires and nanotubes to be used in the sensing devices, because of their sensor performance and low power consumptions. The power will be provided by integrated dye-sensitised solar cells, with the capability to send data over wireless links to provide remote monitoring systems.
Project funded by the Queensland Government through the Smart Futures National and International Research Alliances Program.

Collaborations: CQU, University of Roma Tor Vergata (Italy), University of Brescia, Dyesol

Polymer Solar cells
We are exploring the development of low cost alternative solar cells by using conductive polymers mixed with carbon nanotubes. The understanding and the optimization of the electronic and physical interactions between polymeric donors and acceptor material is a crucial step towards higher efficiency. Mixtures of regioregular poly(3-hexyl-thiophene) rrP3HT and multiwall carbon nanotubes have been investigated by scanning tunnelling microscopy in ultrahigh vacuum, obtaining stunning images of their architecture. Our result highlights the fundamental role played by the CNT chirality in the interaction with rrP3HT. The structural arrangement is also expected to have consequences in the electrical behaviour of the local p-n heterojunction.

Collaborations:  University of Roma Tor Vergata (Italy), Université du Quebec (Canada)

Ref: Applied Physics Letters, 95(1). 013304-1 (2009).

Grants

Ultra High Vacuum Scanning Probe Microscope Facility

Chief Investigators N.  Motta, J. Bell, J. Shapter, E. Quinton, J. Drennan, E. Waclawik, L. Wang, A. Oloyede, T. Bostrom, M. De Crescenzi, E. Gray
Funding Source ARC LIEF
Funding $ 800,000
Year 2010

Solar powered nano-sensors for data acquisition and surveying in remote areas

Chief Investigators N.Motta, J.M. Bell, E. Waclawik, T Tesfamichael, M. Bhagavathi, G. Faglia, M. Ferroni, M. De Crescenzi, A. Di Carlo, A.Sgarlata, M.Scarselli, D.Midmore, A.Thein. S.Tulloch
Funding source  Queensland Smart Futures NIRAP funds
Funding    $1,452,877
Year 2009-2012 (3 years)

Italian-Australian School/Workshop NanoE3
 

Chief Investigators N.Motta, J.M.Bell, F.Rosei
Funding Source DEST+ others
Funding $70,000
Year 2007

 Microscopic study of a polymer-nanotube mixture for organic photovoltaics applications

Chief Investigators N.Motta, J.M. Bell, E. Waclawik, T Tesfamichael, F.Rosei
Industry Partner US AirForce AOARD
Funding $34,773
Year 2006
Website http://www.bee.qut.edu.au/research/projects/photovoltaics/
 
Modifying Structure and Properties of Carbon Nanotubes for Device Applications

Chief Investigators J.M. Bell, E. Waclawik, B. Wei, H. Zhou, N. Motta
Funding Source ARC International Linkage
Funding $ 116,480
Year 2005/2008 (3 years)
 
Growth of semiconductors quantum dots on nanopatterned substrates

Chief Investigators N. Motta, M. De Seta, G. Capellini M. Fanfoni, F. Patella
Industry Partner Ministry of Research and Education – Italy COFIN 2002023125
Funding 294,000 Euro
Year 2002/2004 (2 years)
 
Fabrication organisation and use of memories obtained by Focused Ion Beam.

Chief Investigators N. Motta, A. Balzarotti, A. Sgarlata + 6 European partners
Source of Funding European Community IST-2000
Funding 250,000 Euro
Year 2001/2004 (3 years)

VT-STM Laboratory

Chief Investigators N. Motta, A.Balzarotti, A.Sgarlata, M.Fanfoni, F.Patella
Source of Funding INFM Italy – Large Instruments Funding
Funding 380,000 Euro
Year 1998

Heterostructures of Silicides on Silicon

Chief Investigators M.de Crescenzi, N.Motta, and 11 European Partners
Source of Funding EC Network
Funding 400,000 Euro
Year 1993

Career History

2010-Present: Principal research fellow, Queensland University of Technology, School of Engineering Systems

2004-2009: Adjunct Associate Professor, Queensland University of Technology, School of Engineering Systems,

2001-2004: Associate Professor, Università “Roma TRE”, Department of Physics

1984-2001: Assistant professor, Università di Roma “Tor Vergata”, Department of Physics