In this work PbMoO4 and Pb12xCaxSrxMoO4 (x = 0.1, 0.2, 0.3, 0.4 and 0.5) solid solutions have been
successfully prepared, for the first time, by a simple co-precipitation method and the as-synthesized
samples were subjected to a water-based reflux treatment. Structural characterization of these samples
was performed using X-ray diffraction with Rietveld refinement analysis and Raman spectroscopy. Their
optical properties were investigated by UV-Vis absorption spectroscopy and PL emissions, and the
photocatalytic activity of the as-synthesized samples for the degradation process of Rhodamine B has
been demonstrated. The surface structure and morphologies were characterized by field emission
scanning electron microscopy. To complement and rationalize the experimental results, the geometry,
electronic structures, and morphologies of as-synthesized samples were characterized by first-principles
quantum-mechanical calculations at the density functional theory level. By using Wulff construction,
based on the values of the surface energies for the (001), (100), (110), (111), (011) and (112) surfaces, a
complete map of the available morphologies for PbMoO4 was obtained and a good agreement between
the experimental and theoretical predicted morphologies was found. The structural and electronic
changes induced by the substitution of Pb by Ca and Sr allow us to find a relationship among
morphology, the electron-transfer process at the exposed surfaces, optical properties, and
photocatalytic activity. We believe that our results offer new insights regarding the local coordination of
superficial Pb/Ca/Sr and Mo cations (i.e., clusters) on each exposed surface of the corresponding
morphology, which dictate the photocatalytic activities of the as-synthesized samples, a field that has
so far remained unexplored. The present study, which combines multiple experimental methods and
first-principles calculations, provides a deep understanding of the local structures, bonding,
morphologies, band gaps, and electronic and optical properties, and opens the door to exploit the
electrical, optical and photocatalytic activity of this very promising family of materials