Dye-Sensitized (DSSC) and Perovskites Solar Cells (PSC): Materials and Devices

Our group is involved with the design, synthesis, and characterization of organic and organometallic materials and devices for third generation photovoltaics, including liquid and solid-state n- and p-dye-sensitized solar cells (n-DSSC and p-DSSC), perovskite-based solar cells (PSC). DSSCs, pioneered by Michael Grätzel and thus commonly referred to as Grätzel cells, feature a network of disordered and inexpensive TiO2 nanoparticles coated with light-harvesting dye molecules and typically surrounded by a liquid-phase electrolyte or hole conductor. Photons captured by the dye generate electron-hole pairs which separate at the surface of the nanoparticles. Electrons are injected and transported through the TiO2 layer while positive charges migrate via the electrolyte to the opposite side of the cell. Our work, in collaboration with national and international private and public partners, focuses on the synthesis of new materials photosensitizers, semiconductor oxides and electrolytes with tailored properties and optimized performances thanks to the use of a fruitful combination of electron-rich and electron-poor (hetero)aromatic building units, a variety of structural design, and different symmetries and geometries. Recently, we focused our attention on the investigation of electrolyte solutions containing eco-friendly solvents, namely Deep Eutectic Solvents (DES). DES are a novel class of solvents consisting of an eutectic mixture of two or more components, a quaternary ammonium salt (such as Choline Chloride, vitamin B4) and an hydrogen bond donor (urea, glycerol, water, etc). These components are usually nontoxic, non-volatile and cheap materials, that make DES a very eco-friendly alternative to Volatile Organic Compounds.

In the field of PSC (perovskite-based solar cells), we are interested in new organic molecular and polymeric components as organic precursors for the perovskite layer and as HTM, semi-transparent PSC and lead-free PSC.

In the frame of MIB-SOLAR Center and its facilities, the group also performs fabrication and characterization of DSSC and PSC small cells and modules, also in collaboration with private companies. The best power conversion efficiency top out at ca. 11% (lab scale).

The activity of the group is part of leading European and national networks on optimization and industrial application of DSSCs with grants from Fondazione Cariplo, MIUR-PRIN, FP7, and private companies.

In summary, the DSSC group of Prof. A. Abbotto and Dr. N. Manfredi at MIB-SOLAR Center has been involved in the last years in research for materials and devices for DSSC and PSC. Materials include:

  • organometallic and organic dyes
  • iodine-free electrolytes
  • quasi solid-state DSSC
  • nanostructured TiO2
  • DES as electrolyte solvent
  • perovskites and HTM

Devices include fabrication and characterization of liquid and solid-state cells and modules up to 8×8″. Facilities include:

  • 1000 ft2 ISO 7 clean room
  • screen printers
  • ozone cleaning
  • class ABA solar simulators for cells and modules
  • laser scribing
  • IPCE and APCE
  • glove boxes with spin coaters and evaporators

Research team: Prof. Alessandro Abbotto (Full Professor), Prof. Norberto Manfredi (Associate Professor), PhD Ottavia Bettucci (Assistant Professor), Giorgia Salerno (PhD Student).

Selected Publications and Patents: