From 1988 to 1991 he was responsible for the activities on functional ceramics at the MPI for Metals Research in Stuttgart, and from 1988 to 1996 he taught defect chemistry at the Massachusetts Institute of Technology.
In 1991 he was appointed Scientific Member of the Max Planck Society, Director at the MPI for Solid State Research and Honorary Professor at the University of Stuttgart.
Joachim Maier is Editor-in-Chief of Solid State Ionics and on the board of a number of scientific journals.
Maier's major research fields comprise physical chemistry of the solid state, thermodynamics and kinetics, defect chemistry and transport in solids, ionic and mixed conductors, boundary regions and electrochemistry.
Nanoionics refers to questions of ion transport, stoichiometry and reactivity in confined systems and is of equal significance for chemistry, physics and biology.