15/07/2019 12:00 "Preparation and characterization on the atomic scale for efficient direct solar water splitting" by Hannappel Thomas

15/07/2019 12:00 Professor Hannappel Thomas from Ilmenau University of Technology, Department of Mathematics and Natural Science, Institute for Physics Fundamentals of energy materials will give a lecture at SCAMT.

"Preparation and characterization on the atomic scale for efficient direct solar water splitting" 

Abstract:

Photoinduced reactions in semiconductors are representing topical scientific fields, where interfaces play a decisive role for efficient applications. The key to specifically tune these interfaces is a precise knowledge of interfacial structures and their formation on the microscopic, preferably atomic scale. The talk introduces epitaxial III-V and group-IV semiconductor preparation and corresponding critical interfaces significant for efficient processes in energy conversion. It highlights appropriate analysis strategies capable of monitoring crucial physicochemical interfacial reactions in situ during non‐vacuum preparation and photoactivity studies. Interface formation, structure, photochemical interfacial reactions, and charge carrier dynamics are scrutinized in order to accelerate progress in the realization of efficient energy materials. I will explain an example of a monolithic water-splitting PEC tandem device that exhibits an initial solar-to-hydrogen efficiency of 19 % in acid electrolytes and an efficiency of > 18 % at neutral pH conditions (under simulated AM 1.5 sunlight).