Solar Hydrogen

Researchers in this group are investigating Zn(Cd)O as a photoanode material in photoelectrochemical celsl (PEC) in which various photoanode structures are studied by optical and electrochemical means with the objective of increasing the efficiency of PEC cells.

Hydrogen is the preferred energy carrier for tomorrow´s environmentally acceptable energy systems, which should be able to replace fossil fuels on a time scale of 20-50 years. Hydrogen offers clear advantages for use in mobile applications, energy storage and electrical net load balancing. The most promising method of hydrogen generation using a renewable energy source is based on solar photoelectrochemical (PEC) water decomposition.  The overall objective of this group, therefore, is to develop a better understanding of the mechanisms behind PEC water splitting with a primary focus on the band gap and doping engineering in multilayered semiconductor electrodes. The properties of photoelectrodes meet several specific requirements in terms of semiconductors, electrochemistry and chemical stability. The group is developing monolithic oxide multilayered (MOM) electrodes, where different oxide components provide the necessary functions, such as corrosion stability or efficient light absorption, while also minimizing the risk associated with the formation of isolating layers at the interfaces. One approach for MOM electrodes is to combine a chemically stable protecting layer (for example TiO2 based) thin enough to exhibit carrier tunnelling properties with a CdO/ZnO/MgO multilayer light absorbing structure.

The project is a part of the SolarH2-network established on behalf of the Nordic Energy Research Association (N-INNER).

 

In the context of this effort, researchers have three sub-goals:

  • an investigation of the optimal profiles of Mg, Zn and Cd through the MOM structure
  • study of electronic doping issues in Zn(MgCd)
  • study of the tunneling properties of the TiO2 combined with corrosion resistivity

Andrej Kuznetsov