The invention relates to VERY stable electroactive nanofluids comprising graphene-based compounds, and the production methods thereof. The invention also relates to the use of said electroactive nanofluids as liquid electrodes for the storage of energy in flow cells.

A low temperature, liquid metal approach provides a metal-air battery at room temperature or slightly above for high current density, using ambient oxygen as an electrode without the need for high heat for an opposed metal electrode. A metal-air battery employs a low melting point metal such as gallium for an all-fluid battery having a flowing aqueous electrolyte for maintaining a large volume of electrical storage capacity separate form a relatively small reactor or cell for powering an electrical load. Reversibility of the forward discharge (load powering) reaction provides a recharging capability well suited for grid storage to moderate supply and demand variations. The result is an ultra-high density, rechargeable, safe, grid-scale electricity storage technology as an alternative to lithium-ion and solvent-based flow batteries.

The present invention discloses a process for the synthesis of nitrogen-doped carbon electrocatalyst with good electrochemical stability and fuel tolerance for oxygen reduction reaction (ORR) by pyrolysis of protein-rich pulse flour cooked with SiO2 nanoparticles.

Photoelectrodes and photoelectrochemical redox flow batteries incorporating the photoelectrodes are disclosed. The photoelectrodes include a photoactive semiconductor and a plurality of nanoparticles, each of which includes a plurality of edges and/or points, e.g., nanostars, nanopyramids, nanorods, etc.

Provided are a carbon catalyst, an electrode, and a battery that exhibit excellent activity. A carbon catalyst according to one embodiment of the present invention has a carbon structure in which area ratios of three peaks f.sub.broad, f.sub.middle, and f.sub.narrow obtained by separating a peak in the vicinity of a diffraction angle of 26 in an X-ray diffraction pattern obtained by powder X-ray diffraction satisfy the following conditions (a) to (c): (a) f.sub.broad: 75% or more and 96% or less; (b) f.sub.middle: 3.2% or more and 15% or less; and (c) f.sub.narrow: 0.4% or more and 15% or less.

A particulate carbon catalyst in which particles having a particle diameter of 20 nm-1 m account for a volume fraction of at least 45%, and the content of nitrogen atoms is 0.1-10 atomic % relative to the amount of carbon atoms.

A sacrificial support-based method, a mechanosynthesis-based method, and a combined sacrificial support/mechanosynthesis support based method that enables the production of supported or unsupported catalytic materials and/or the synthesis of catalytic materials from both soluble and insoluble transition metal and charge transfer salt materials.

A method of preparing M-NC catalysts utilizing a sacrificial support approach and inexpensive and readily available polymer precursors as the source of nitrogen and carbon is disclosed. Exemplary polymer precursors include non-porphyrin precursors with no initial catalytic activity. Examples of suitable non-catalytic non-porphyrin precursors include, but are not necessarily limited to low molecular weight precursors that form complexes with iron such as 4-aminoantipirine, phenylenediamine, hydroxysuccinimide, ethanolamine, and the like.

Disclosed is a process for the manufacture of a catalyst-coated membrane-seal assembly, including: (i) providing a carrier material; (ii-i) forming a first layer, the first layer being formed by: (a) depositing a first catalyst component onto the carrier material such that the first catalyst component is deposited in discrete regions; (b) drying the first layer; (ii-ii) forming a second layer, the second layer being formed by: (a) depositing a first seal component, such that the first seal component provides a picture frame pattern having a continuous region and void regions, the continuous region including second seal component and the void regions being free from second seal component; (b) depositing a first ionomer component onto the first layer, such that the first ionomer component is deposited in discrete regions; and (c) drying the second layer.

Novel catalytic materials and novel methods of preparing M-NC catalytic materials utilizing a sacrificial support approach and using inexpensive active polymers as the carbon and nitrogen source and readily available metal precursors are described.