Abstract: An electrocatalyst including a substrate and CoxNiyFe2O4 nanoparticles, where x+y=1. The CoxNiyFe2O4 nanoparticles are doped with 0.01 weight percentage (wt. %) to 1.0 wt. % selenium (Se), based on the total weight of the CoxNiyFe2O4 nanoparticles. Further, the CoxNiyFe2O4 nanoparticles have a polygonal shape, and the CoxNiyFe2O4 nanoparticles are dispersed on the substrate to form the electrocatalyst.

Abstract: A method of generating hydrogen including applying a potential of ?0.1 volts (V) to ?1.0 V to an electrochemical cell, and the electrochemical cell is at least partially submerged in an aqueous solution. Further, on the application of the potential, the aqueous solution is reduced, thereby forming hydrogen. The electrochemical cell includes an electrocatalyst and a counter electrode. The electrocatalyst includes a substrate and vanadium-doped manganese spinel oxide microspheres (MnVxCo2-xO4) particles. The value of x is ?0.4, the MnVxCo2-xO4 particles have a spherical shape, the MnVxCo2-xO4 particles have an average diameter of less than 100 nanometers (nm), and the MnVxCo2-xO4 particles are dispersed on the substrate to form the electrocatalyst.

Abstract: A method of generating hydrogen including applying a potential of greater than 0 to 2.0 V to an electrochemical cell that is partially submerged in an aqueous solution. On applying the potential, water in the aqueous solution is reduced, and thereby forms hydrogen. The electrochemical cell includes an electrocatalyst and a counter electrode. The electrocatalyst includes a substrate, WO3?x nanosheets, and CdS1?y nanospheres, in which, x is from greater than 0 to less than 3 and y is from greater than 0 to less than 1. The CdS1?y nanospheres are dispersed on the WO3?x nanosheets to form a nanocomposite, which is dispersed on a surface of the substrate. The WO3?x nanosheets have an average length of 600-800 nanometers (nm) and an average width of 300-500 nm, and the CdS1?y nanospheres have an average diameter of 10-50 nm.

Abstract: A method of generating hydrogen gas including applying a potential of greater than 0 to 1.0 volts (V) to an electrochemical cell. The electrochemical cell is at least partially submerged in an aqueous solution. On applying the potential the aqueous solution is reduced thereby forming hydrogen gas. The electrochemical cell includes an electrocatalyst and a counter electrode. The electrocatalyst includes a substrate, strontium titanate (SrTiO3) nanoparticles, and cadmium selenide (CdSe) nanoparticles. The SrTiO3 nanoparticles have a substantially spherical shape. The CdSe nanoparticles have a polygon shape. The CdSe nanoparticles are distributed within a network of the SrTiO3 nanoparticles on the surface of the substrate.

Abstract: An electrode includes a transparent substrate, and a layer of a nanostructured material at least partially covering a surface of the transparent substrate. The nanostructured material includes defective perovskite nanostructures (DPNSs) in the form of nanoplates having an average particle size in a range of 10 to 100 nanometers (nm), an interplanar spacing d(101) of the (101) plane in a range of 0.3 to 0.4 nm, and an interplanar spacing d(104) of the (104) plane in a range of 0.2 to 0.3 nm. A method of making the electrode.

Abstract: An electrode including a transparent substrate and a layer of a perovskite-based nanocomposite (PTNC) material at least partially covering a surface of the transparent substrate. The PTNC material includes gold (Au) nanoparticles, graphitic carbon nitride (g-C3N4) nanoparticles, and perovskite-based nanoparticles through synergistic interaction. A method of making the electrode is described.