Combinational and High-throughput Methods for the Discovery and
Investigation of Novel Materials
Prof. Alfred Ludwig*
Ruhr University Bochum, Germany
ABSTRACT:
Efficient discovery
and optimization of new materials is a key challenge in materials science: e.g.
new materials for the sustainable production/storage/conversion of energy
carriers are necessary to improve existing and to enable future energy systems.
By implementing and optimizing the thin-film combinatorial materials science
approach in our group for 15 years, we are contributing to this development. It
comprises the fabrication and processing of thin film materials libraries by
combinatorial sputter deposition processes (40 elements available) and optional
post-deposition treatments (e.g. thermal oxidation, annealing, dealloying),
followed by the high-throughput characterization of the thin film samples
contained in the libraries. The importance of defining adequate screening
parameters and the according design of different materials libraries suitable
for one or more screening parameters is addressed. Our high-throughput
characterization methods are automated, fast, and mostly non-destructive: examples are EDX, XPS and RBS for composition, XRD for
crystal structure, temperature-dependent resistance for phase transformation,
high-throughput test stands for optical properties (color, transmission) and
mechanical properties (stress, hardness, elastic modulus), and scanning droplet
cells for photoelectrochemical properties screening. The obtained results for
up to quinary systems are visualized in the form of
composition-processing-structure-function diagrams, i.e. (multi)functional
existence diagrams, interlinking compositional data with structural and
functional properties. The talk will discuss examples of the combinatorial
development of multinary compositionally complex alloys by thin-film
materials libraries and nanoparticle libraries produced by combinatorial
sputtering into ionic liquids. Finally, a new method based on combinatorial
processing platforms is introduced, which allows the accelerated atomic-scale
exploration of phase evolution in compositionally complex alloys.
Prof. Dr. Alfred Ludwig holds the chair for Materials Discovery and Interfaces “at the Institute for Materials of Ruhr University Bochum. He studied mechanical engineering at the University of Karlsruhe, Germany, with a focus on materials science and MEMS. He received his “Dr.-Ing.” from the University of Karlsruhe in 1999 for his work on magnetoelastic thin-film multilayers at the Institute of Materials Research at the Forschungszentrum Karlsruhe. Then he joined the “Center for Advanced European Studies and Research” (Bonn, Germany), research group "Smart Materials" where he focused on the development of high frequency magnetoelastic thin films and devices. From December 2002 to September 2007 he was assistant professor for “MEMS materials” at the Ruhr-University Bochum (RUB), Faculty of Mechanical Engineering and simultaneously head of the caesar research group “Combinatorial Materials Science”. From October 2007 to 2012 he was awarded a German Science Foundation (DFG) Heisenberg-Professorship for “MEMS Materials” at RUB. Since the end of 2012 he continues as a full professor at RUB. From 2011 to 2016 he was the coordinator of the “Materials Research Department” at RUB. He initiated and organized the new research building ZGH “Center for interface-dominated high-performance materials” in which he serves now as managing director. His research interests include combinatorial and high-throughput methods in materials science, MEMS tools for materials science, nanoscale thin films and multilayers, multifunctional materials (e.g. conventional and ferromagnetic shape memory alloys) as well as new materials for energy applications (e.g. solar water splitting materials, electrocatalysts, thermoelectrics,...). He has published more than 270 papers, more than 220 thereof in peer-reviewed journals.