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New yellow inorganic pigments, (BiV)1−x(YNb)xO4 with high NIR reflectance were synthesized by a conventional solid-state reaction method. The effect of isovalent dopants, namely, Y3+ and Nb5+ on BiVO4 samples was characterized using powder X-ray diffractometer, scanning electron microscope, UV–vis–NIR diffuse reflectance spectrometer, and CIE 1976 L*a*b* color scales. The prepared pigments exhibit brilliant yellow colors with significant enhancement of NIR reflectance to 90.8% when compared to undoped BiVO4 at the 1100 nm range. Further, the solid solutions allow fine tuning of the band gap displaying various yellow colors. The lattice distortion and reduction in particle size are responsible for the enhancement of the pigment characteristics. The above results indicate that these yellow pigments have potential to be used as cool colorants for roofs and automotives as energy-saving coatings.

New inorganic pigments based on fluorite solid solutions, Ce 0.95 M x Pr 0.05Àx O 2 (M 5 Zr and Sn; x ranges from 0 to 0.05) have been prepared by the conventional solid-state route with a goal of preparing environmentally benign colorants. The pigments obtained displayed better color characteristics than that of Ce 0.95 Pr 0.05 O 2 system showing colors from brick red to dark brown. The coloring mechanism is based on the introduction of an additional electronic energy level of unpaired 4f electron of the praseodymium ion into the cerianite band. Further, the cosubstitution of Zr or Sn in Ce 0.95 Pr 0.05 O 2 system raises the slope of the absorption edge with a blue shift resulting in enhanced lightness. Their applicability for wide spread use, chemical and thermal stability, and capacity to produce pigmentation in plastics, has been investigated. These findings suggest that the developed red pigments may form a viable and potential alternative to traditional toxic red pigments such as cadmium sulfoselenide.