The Laboratory for Transient Absorption and Photoacoustics is located in the 2nd floor (E floor) of the building of the Department of Chemistry of the Faculty for Sciences and Technology of the University of Coimbra. The laser laboratories are dedicated to transient absorption spectroscopy and photoacoustic calorimetry. The laboratory has four main working stations and is linked to auxiliary preparative laboratories, cell culture laboratory and office space. Two of the main working stations are dedicated to Photoacoustics and the other two to Transient absorption. The Photoacoustic working stations comprises instrumentation for ms/ns/ps time resolved Photoacoustic Calorimetry and Photoaocustic Tomography. For Transient absorption the laboratory has ns laser flash photolysis and fs pump-probe spectroscopy set-ups. The laboratory is equipped with pipes for handling laboratory gases and accessories for working at distinct temperatures and deal with solid and liquid samples. Singlet oxygen detection is also possible in the Laboratory. A fifth working station, in a separated room, is dedicated to the preparation and characterization of solar cells. The laboratories are acclimatized and are located close to each other as well as to the work offices of the research team members.
The following specific main equipment is available in the LPR:
Home-made time-resolved photoacoustic calorimetry flow cells, includes temperature controlled cells and automatic injection models (SSI model 300 LC pump; Kloehn syringe pump).
Panametrics/Olympus 0.5, 2.25, 10, 50, 100, 225 MHz transducers and 20 MHz hydrophone for photoacoustic detection.
Available pulsed excitation sources for photoacoustic: PTI PL 2300 nitrogen laser and PTI PL 202 dye laser; Spectra Physics Quanta-Ray ns Nd:YAG laser; EKSPLA 2143A ps Nd:YAG laser; EKSPLA NL301G ns Nd:YAG laser; EKSPLA OPO model PG-122; Quantel Big Sky Ultra 50 Nd:YAG laser attached to a second harmonic generator.
Digital oscilloscopes: Tektronix DSA 601, Tektronix TDS 3000D and Tektronix DPO 7254.
Flash photolysis Applied Photophysics LKS.60 (includes the Nd-Yag/1.5J/8ns laser Spectra Physics Quanta-Ray model second, third and fourth harmonic generator and Tektronix TDS 3000D oscilloscope). Singlet Oxygen Detection with cooled Photomultiplier Tube IR Hamamatsu R5509-42, 600 lines gratting.
Excitation and analyzing sources available for Flash photolysis: PTI PL 2300 nitrogen laser and PTI PL 202 dye laser; Spectra Physics Quanta-Ray ns Nd:YAG laser; EKSPLA 2143A ps Nd:YAG laser; EKSPLA NL301G ns Nd:YAG laser; EKSPLA OPO model PG-122; Quantel Big Sky Ultra 50 Nd:YAG laser attached to a second harmonic generator, Lynx Tec 500 diode laser 633 nm, 649 nm, 748 nm (10-40 mW) , Custum made Hamamatsu diode lasers 748 nm (100 mW).
Helios broadband pump-probe femtosecond transient absorption spectrometer: includes an Ultrafast Amplifier System Solestice from Spectra-Physics comprising a regenerative amplifier, a stretcher/compressor and seed (mode locked Ti:sapphire Mai Tai) and pump (Nd:YLF Empower) lasers. The resulting 110 fs, 795 nm output is used for excitation (pump) with the use of a Light Convertion TOPAS Prime OPO for obtaining the desired wavelength. A fraction of the 795 nm beam is used to create a white UV, Vis or NIR light continuum (probe). The instrument response function for the pump-probe experiments is about 150 fs.