  Transition metal perovskite chalcogenides (TMPC) are a new class of
semiconductor materials with broad tunability of physical properties due to
their chemical and structural flexibility. Theoretical calculations show that
band gaps of TMPCs are tunable from Far IR to UV spectrum. Amongst these
materials, more than a handful of materials have energy gap and very high
absorption coefficients, which are appropriate for optoelectronic applications,
especially solar energy conversion. Despite several promising theoretical
predictions, very little experimental studies on their physical properties are
currently available, especially optical properties. We report a new synthetic
route towards high quality bulk ceramic TMPCs and systematic study of three
phases, SrZrS3 in two different room temperature stabilized phases and one of
BaZrS3. All three materials were synthesized with a catalyzed solid-state
reaction process in sealed ampoules. Structural and chemical characterizations
establish high quality of the samples, which is confirmed by the intense room
temperature photoluminescence (PL) spectra showing direct band gaps around
1.53eV, 2.13eV and 1.81eV respectively. The potential of these materials for
solar energy conversion was evaluated by measurement of PL quantum efficiency
and estimate of quasi Fermi level splitting.
