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: An electrode includes an electrically conductive substrate and a layer of a molybdenum-doped zinc/cobalt oxide (ZnCo2-xMoxO4). The surface of the electrically conductive substrate is at least partially covered by the layer of ZnCo2-xMoxO4, where x is a positive number equal to or less than about 0.1, and the layer of the ZnCo2-xMoxO4 includes spherical-shaped particles. The electrode has a Tafel slope from 75 millivolts per second (mV/s) to 115 mV/s, and a potential of 0.27 to 0.30 volts relative to the reversible hydrogen electrode (VRHE) at a current density of about 50 mA/cm2 for a duration of at least 40 hours.

Abstract: Systems and methods include the following. Information about a first electronic communication device is transmitted to at least one server and/or decentralized infrastructure. The information includes vicinity information. A status signal associated with a first user of the first electronic communication device is optionally transmitted. Contact proximity network information about a contact proximity network is received. The contact proximity network is based on the information from a plurality of electronic communication devices and information about the association between users and electronic communication devices. The contact proximity network information includes status signal information and interconnected nodes corresponding to different users and pairwise connections between users based upon their relative physical space and time proximity.

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.

Abstract: Systems and methods include the following. Information about a first electronic communication device is transmitted to at least one server and/or decentralized infrastructure. The information includes vicinity information. A status signal associated with a first user of the first electronic communication device is optionally transmitted. Contact proximity network information about a contact proximity network is received. The contact proximity network is based on the information from a plurality of electronic communication devices and information about the association between users and electronic communication devices. The contact proximity network information includes status signal information and interconnected nodes corresponding to different users and pairwise connections between users based upon their relative physical space and time proximity.

Abstract: Systems and methods include the following. Information about a first electronic communication device is transmitted to at least one server and/or decentralized infrastructure. The information includes vicinity information. A status signal associated with a first user of the first electronic communication device is optionally transmitted. Contact proximity network information about a contact proximity network is received. The contact proximity network is based on the information from a plurality of electronic communication devices and information about the association between users and electronic communication devices. The contact proximity network information includes status signal information and interconnected nodes corresponding to different users and pairwise connections between users based upon their relative physical space and time proximity.

Abstract: Systems and methods include the following. Information about a first electronic communication device is transmitted to at least one server and/or decentralized infrastructure. The information includes vicinity information. A status signal associated with a first user of the first electronic communication device is optionally transmitted. Contact proximity network information about a contact proximity network is received. The contact proximity network is based on the information from a plurality of electronic communication devices and information about the association between users and electronic communication devices. The contact proximity network information includes status signal information and interconnected nodes corresponding to different users and pairwise connections between users based upon their relative physical space and time proximity.