Methods, structures, devices and systems are disclosed for fabrication of microtube engines using membrane template electrodeposition. Such nanomotors operate based on bubble-induced propulsion in biological fluids and salt-rich environments. In one aspect, fabricating microengines includes depositing a polymer layer on a membrane template, depositing a conductive metal layer on the polymer layer, and dissolving the membrane template to release the multilayer microtubes.

A simplified and efficient method for preparing non-noble metal catalysts for oxygen reduction reaction (ORR) based on nitrogen containing metal organic framework (MOF) is provided. The method includes formation of a first MOF product through a mechano-chemical reaction between a first transition metal compound and a first organic ligand in the presence of a catalyst. It further includes formation of a second MOF product incorporating a second transition metal and a second organic ligand into the first-MOF product. The second MOF product is converted into an electrocatalyst via pyrolysis, and optionally post-treatment. The electrocatalysts are applicable in various electrochemical systems, including oxygen depolarized cathodes (ODC) for chlorine evolution.

An electrolytic gas suction tool includes: a battery; a control substrate which controls power supply from the battery; a pair of positive and negative electrodes which are electrically conducted to or cut off from a positive electrode and a negative electrode of the battery by the control substrate; an electrolysis tank which is capable of storing water and into a lower part of which the pair of positive and negative electrodes are inserted in the mounted state; and a heater device which is heated to generate nicotine containing steam upon receiving the power supply from the battery by the control substrate.

ABSTRACT OF THE DISCLOSURE A catalyst for electrochemical ammonia synthesis incudes a carbon carrier composed of carbon; and 20-65 wt% of iron, copper and sulfur, based on weight of the carbon, supported in the carbon carrier. The catalyst may be coated on an electrode selected from the group consisting of carbon paper, carbon cloth, carbon felt, fluorine- doped tin oxide (FTO) conducting glass, and combinations thereof by spray coating, screen printing or ink jet printing. The catalyst has an ammonia synthesis activity up to several times to several tens of times of the activity of the existing single metal or metal oxide catalysts. Thus, when using the catalyst, it is possible to provide a method for electrochemical ammonia synthesis having an improved ammonia production yield and rate.

A heterojunction composite material consisting of one-dimensional In.sub.2O.sub.3 hollow nanotube and two-dimensional ZnFe.sub.2O.sub.4 nanosheets and its application are disclosed. When using this material for catalytic reactions, the hollow cavity and two-dimensional nanosheets of hollow nanomaterials can not only reduce the migration distance to accelerate the electron-hole separation, but also provide a large surface area and rich active sites to promote pollution adsorption and surface catalysis. At the same time, multiple light scattering or reflection in the hollow cavity of the hollow nanomaterials can increase light absorption and utilization. In addition, the heterojunction photocatalyst constructed by growing two-dimensional semiconductor nanosheets on a tubular substrate can promote the effective separation of photogenerated electrons and photogenerated holes, thereby improving the catalytic efficiency. In terms of catalytic performance, In.sub.2O.sub.3 @ ZnFe.sub.2O.sub.4 shows effective degradation of tetracycline, and due to its ferromagnetism, it shows convenient and good separation effect and has good recycling performance.

Catalysts for selective production of hydrogen peroxide and methods of making and using thereof have been developed. The catalysts include an alloyed or doped metal oxide which permits tuning of the catalytic properties of the catalysts for selection of a desired pathway to a product, such as hydrogen peroxide. The catalysts may be incorporated into electrochemical or photochemical devices.

A method for separation of at least one catalyst or adsorbent from a homogeneous mixture of catalysts or adsorbents, used in a method for treatment of gas or hydrocarbon feedstock, in which the grains of catalysts or adsorbents are separated according to a sorting threshold corresponding to a content of the constituent element that is sought and defined by the user.

A novel catalyst includes a plurality of nanoparticles, each nanoparticle including a core made of a catalytic metal and a porous shell surrounding the core, made of metal oxide, the porous shell preserving a catalytic function of the core and reducing reduction of the core and coalescence of the nanoparticles.

Disclosed is a method for making a material having supported micro- and/or nanostructures, the method includes (a) obtaining a substrate comprising a precursor material and an electrically conductive layer of micro- or nanostructures embedded into at least a portion of a first surface of the substrate, and (b) applying a voltage across the electrically conductive layer to heat the micro- or nanostructures, wherein the heat converts the precursor material into micro- and/or nanostructures.

Nickel electrodes comprising an electrically conductive nickel sheet and a nickel layer deposited thereon which consists of spherical, porous nickel particles which adhere to each other, made by the method of partially reducing spherical nickel hydroxide particles in a reducing atmosphere at elevated temperatures to obtain partially reduced spherical Ni/NiO particles, preparing a paste from the Ni/NiO particles obtained and an organic and/or inorganic binder as well as further excipients as required, applying the paste in a layer to one or both sides of the electrically conductive nickel sheet, and tempering the coated nickel sheet in a reducing atmosphere at elevated temperatures. Self-supporting nickel layers of spherical, porous nickel particles which adhere to each other. Producing nickel electrodes and the self-supporting nickel layer, and use thereof, particularly as an electrode for water electrolysis.