Facilities and Methods

Facilities

Methods

The experimental methods employed are:

• Current/radiance vs voltage curves to characterize polymer LEDs for their performance (brightness, quantum efficiency...) and for the underlying physics. Temperature dependance is studied using a cryostat. Radiance (W/cm²) is measured with a Si-photodiode that has been calibrated with an integrating sphere and a calibrated halogen lamp.
  
• Emissionspectra analysis and CIE color coordinates calculation
  
• Photovoltaic measurements with a Xenon lamp
  
• Transport studies and 1/f noise analysis at the metal insulator transition of carbon black polymer composites are studied using the cryostat.
  
• The Scanning Probe Microscope allows surface characterization and imaging down to the nanometer scale in different operation modes (Atomic Force-, Noncontact- , Scanning Tunneling-Mode)
  
• Photoluminescence studies with the confocal optical microscope with micrometer resolution
  
• Optical analysis of thin films yields determination of film thicknesses by measuring reflectivity- and transmission-spectra
  
• Lifetime studies with automated setup
  
• Impedance spectroscopy for the determination of capacitance vs bias curves and equivalent circuit models of polymer devices
  
• Photoluminescence measurements for liquid and film using a PerkinElmer LS 45 luminescence spectrometer for optical
  characterization
  
• Cyclic voltammetry for the electrochemical characterization of materials using an EG&G Model 362 scanning potentiostat and BAS low-volume electrochemical cell setup.