Low-cost and earth abundant, Ni.sub.1−xMo.sub.x alloy nanocrystals, with sizes ranging from 18-43 nm and varying Mo composition (0.0-11.4%), were produced by a colloidal chemistry method for alkaline HER reactions. For a water splitting current density of ˜10 mA/cm.sup.2, these alloys demonstrate over-potentials of −62 to −177 mV, which are comparable to commercial Pt-based electrocatalysts (−68 to −129 mV). The cubic Ni.sub.0.934Mo.sub.0.066 alloy nanocrystals exhibit the highest activity as alkaline HER electrocatalysts, outperforming commercial Pt/C (20 wt %) catalyst.

An electrolyzer for splitting molecular water into molecular hydrogen and molecular oxygen using electrical energy comprises an anodic half-cell with an anode and a cathodic half-cell with a cathode. The anodic half-cell and the cathodic half-cell are separated from each other by a separator. The anodic half-cell comprises an anodic electrolyte, which is in contact with the anode. The cathodic half-cell comprises a cathodic electrolyte, which is in contact with the cathode. The anodic half-cell comprises an anodic catalyst. The cathodic half-cell contains at least one cation complex for forming at least one mediator complex. The at least one cation complex is reducible to the mediator complex by taking up at least one electron at the cathode. The mediator complex is a catalytically active chemical complex for splitting the molecular water (H.sub.2O) into molecular hydrogen (H.sub.2) and hydroxide ions (OH.sup.−) while releasing at least one electron.

Electrode catalytic layers coated on outer surfaces of oxidation electrode and a reduction electrode used to generate sterile water, where the electrode catalyst layers are formed on the outer surfaces of the oxidation electrode and a reduction electrode to have predetermined thickness, and are composed of iridium (Ir), palladium (Pd), and tantalum (Ta), and wherein the palladium (Pd) has a weight ratio of 10% to 30%, and a sum of the weight ratios of the iridium (Ir) and the tantalum (Ta) is 70% to 90%.

An electrode catalyst is configured such that non-noble metal particles, noble metal particles or nitride-doped noble metal particles are supported on a carbon support, wherein the carbon support has a 2D planar crystal structure or a 3D polyhedral crystal structure and is doped with nitrogen, thereby exhibiting increased catalytic activity.

A method for electrolysis of water and a method for preparing a catalyst for electrolysis of water are provided. The method for electrolysis of water includes using a high entropy alloy as a catalyst. Further, the method for preparing a catalyst for electrolysis of water includes the steps of placing a substrate in an aqueous electrolyte containing a high entropy alloy precursor and performing an electroplating process on the substrate to form a high entropy alloy catalyst on the substrate.

This electrode catalyst of the present invention contains an electrically conductive material that supports a metal or a metal oxide, wherein electrical conductivity at 30° C. is 1×10.sup.−13 Scm.sup.−1 or greater.

A ruthenium-copper (RuCu) nano-sponge (NSP) electrocatalyst for use in the electrolytic reduction of nitrogen to provide ammonia is described. The RuCu NSP can be prepared as a porous nanoparticle comprising a RuCu alloy via facile reduction of Ru and Cu precursors under ambient conditions. Electrodes prepared with surface disposed RuCu NSPs can be used to prepare ammonia from nitrogen with good yields and Faradaic efficiency at room temperature and atmospheric pressure.

The present disclosure relates to a system for generating hydrogen (H.sub.2) from an aldehyde, where the system comprises an anode comprising a metal-based alloy catalyst, a cathode comprising Ni.sub.2P or Pt/C, and a separator positioned between the anode and the cathode. Also disclosed is a method of producing hydrogen (H.sub.2). This method involves providing a system described herein and adding an aldehyde to the system under conditions effective to produce hydrogen (H.sub.2) from electrocatalytic oxidative dehydrogenation of the aldehyde at the anode and water reduction at the cathode.

The present disclosure relates to a system for generating hydrogen (H.sub.2) from an aldehyde, where the system comprises an anode comprising a metal-based alloy catalyst, a cathode comprising Ni.sub.2P or Pt/C, and a separator positioned between the anode and the cathode. Also disclosed is a method of producing hydrogen (H.sub.2). This method involves providing a system described herein and adding an aldehyde to the system under conditions effective to produce hydrogen (H.sub.2) from electrocatalytic oxidative dehydrogenation of the aldehyde at the anode and water reduction at the cathode.

The present application discloses a photoelectrode and a preparation method therefor, and a Pt-based alloy catalyst and a preparation method therefor. The method for preparing the Pt-based nano-alloy catalyst includes: placing a photoelectrode in an electrolytic cell with at least one light-transmitting surface and including an electrolyte; using a light source to irradiate a surface of the photoelectrode from the light-transmitting surface of the electrolytic cell, where the photoelectrode includes an active metal layer, a passivation layer, a semiconductor light absorption layer, a rear conductive layer, and an insulating protective layer that are sequentially stacked along the light incident direction; based on an electrochemical workstation and light irradiation, using a Pt electrode and a reference electrode to match the photoelectrode to electrochemically treat the surface of the photoelectrode; and cleaning the electrochemically-treated photoelectrode to obtain the Pt-based nano-alloy catalyst and a photoelectrode modified by the Pt-based nano-alloy catalyst.