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NANOMATERIALS FOR ENVIRONMENT AND OPTO-ELECTRONICS
The research activity is organised in different
fields - synthesis and characterisation of II-VI
semiconductor and oxides nanocrystals - design
and assembly of nanostructured functional
systems - optoelectronic and photocatalytic
applications (photovoltaics devices,
(bio)sensors, photodegradation of organic
pollutants)
Applied research activity
Fundamental studies
Design and investigation of systems for
preparation of nanostructured materials
Synthesis of colloidal nanocrystals
Applications
Diagnostics and characterization
Development of semiconductor nanoparticles system
for (bio)sensing application
Techniques for nanoparticle and assembly
characterization
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Synthetic approaches to colloidal nanocrystals

• Solution-based approaches
• growth in self-assembled organic templates
• growth in coordinating agents

Use of coordinating agents

• Advantages
• high-quality samples
• gram quantities
• fast
• easy to learn
• low cost
• Real time monitoring

• Post-Preparation Processing
• size-selective precipitation
• band-gap engineering
• ligand exchange

Use of organic templates (reverse micelles)
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Nanocrystals can be easily processed and can be
immobilised onto proper substrate by self
assembling, spin coating, casting etc.
Self-Assembled Monolayers
Self-organization of close-packed 2D/3D
nanocrystal structures
Murray et al. Ann. Rev. Mater. Sci. 2000
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Diagnostic and Characterisation

• Optical studies (stedy state and time resolved
  spectroscopies at low and high excitation
  intensity)
• Stochastic Kinetic Simulations are utilised to
  account for the observed template effect of the
  microemulsion aggregate size on the nanocluster
  growth.
• Calorimetric investigations to characterise the
  growth processes of colloidal nanocrystals and
  the energetic state of the obtained particles.
• Electrochemical characterization of
  nanostructured assemblies

Photocurrents recorded in a photovoltaic cell
formed by TiO2 nanocrystals and chlorophyll
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• Applications of colloidal dots
• Fundamental studies, both on ensembles and on
  single particles
• Single electron devices
• Chromophores in biological labelling experiments
  and in light emitting diodes
• Colloidal dots in photovoltaic devices and
• Transducers in chemical sensors (biosensor)
• Photocatalysis in environmental technology

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PHOTODEGRADATION OF ORGANIC POLLUTANTS
Test of nanocrystals efficiency in photocatalysis
for their application in the photoinduced
oxidation for decontamination of organic water
pollutants
NANOCRYSTALLINE STRUCTURE COUPLED TO
HOTOSYNTHETIC PIGMENTS FOR ENERGY PHOTOCONVERSION
Set up of photoelectrochemical systems coupling
semiconducting nanocrystalline electrodes to
organic photosynthetic dyes for photovoltaic
devices with low environmental impact
Chlorophyll a Carotenoids
Chlorophyll a
Carotenoids
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HETEROJUNCTION BASED ON INORGANICSEMICONDUCTOR
NANOCRYSTALS AND ORGANIC SEMICONDUCTOR POLYMERS
FOR OPTO-ELECTRONIC APPLICATION

• Preparation of hybrid heterostructure
• Morphological, optical and electric
  characterisation of heterostructures
• Electrochemical investigation

Color tunability. Long lifetimes. Ease of
processing.
Nanocrystals/Polymers Composite for Photovoltaic
Devices
DEVELOPMENT OF A NOVEL ENZYME/SEMICONDUCTOR
NANOPARTICLES SYSTEM FOR BIOSENSOR APPLICATION
Biosensors based on the possibility of modulating
particle size of semiconductor nanocrystals and,
consequently, their properties for fast and low
cost detection of food and agriculture related
compounds.
Photoinduced oxidation of formaldehyde to formic
acid using FDH coupled to CdS as charge carrier
mediator instead of NAD co-factor