% reductions Catalyst activity Charge transfer Comparatives studies Corrosion resistance Counter electrode Counter electrodes Cyclic voltammetry Dimethylformamide Dye- sensitized solar cells Dye-sensitized solar cells Electrochemical impedance spectroscopy Electrodes Energy dispersive X ray spectroscopy Energy dispersive spectroscopy FeSe2 Field emission microscopes High resolution transmission electron microscopy Iron compounds Mild hydrothermal method NiSe2 Nickel compounds Organic solvents Polyelectrolytes Potassium hydroxide Scanning electron microscopy Selenides Selenium compounds Simple++ Solar power generation