Measurements of ionization potentials and HOMO energy levels using cyclic voltammetry method

Unit: Faculty of Physics
Keywords: Cyclic voltammetry, potential of oxidation and reduction, ionization potential, HOMO, LUMO, organic electronics, OLED, solar cells, sensors

Cyclic voltammetry is dynamic potentiostatic tool for analysis of electrochemical reactions in solution. Principle of the method: changing potential of one of the electrodes in the three electrode system the relative current is measured.

From this specific potential of oxidation and reduction are determines which allow to calculate energy of HOMO and LUMO levels. For accurate determination of HOMO LUMO energy levels calibration is needed with material of know HOMO level and reversible REDOX process (often ferrocene is used with HOMO energy of -4.8 eV).
Compounds should dissolve in common organic solvents, do not react with electrolyte (tetrabutylamonium perchlorate) and etch contacts or electrochemical cell.
Current range: 20 nA – 100 mA.
Maximal input voltage: 10 V.
Input resistance: 1013 Ω.
Gain: 10 mA/V, 100 μA/V, 1 μA/V, 100 nA/V.
DC drift <10 μV/°C;
Glassy carbon, platinum and gold working electrodes, Ag/AgCl reference electrode, anode Pt/Ti.
Maximal potential window from -2V to 2V.

Application. Characterization of ionization potential or HOMO energy level of new organic compounds will enable to evaluate their potential for applications in organic electronic devices (organic light emitting diodes, organic solar cells, sensors). 

Contacts: Dr. Karolis Kazlauskas, tel.+370 600 34126,