Herein, a new method for synthesizing advanced nanocomposite materials based on tungsten, molybdenum, and titanium oxides by pulsed underwater plasma is reported. This is an environmentally friendly, energy-saving, and simple method for obtaining bimetallic oxide nanoparticles with inhomogeneous defect structures. The chemical composition and morphology of the obtained particles are explored by electron microscopy and X-ray diffraction spectroscopy. Four types of mixed-oxide particles of tungsten–molybdenum and tungsten–titanium are synthesized and used to make the photoanodes for dye-sensitized solar cells (DSSCs). The best DSSC shows a fill factor of 51% and a short-circuit current density of 4.8 mA cm−2, resulting in a conversion efficiency of 4.11% and an improvement over the cells prepared from pure titanium or tungsten oxides.
