The present invention relates to a hybrid system for water treatment, desalination, and chemical production. The hybrid system of the present invention includes a photoanode, an anode chamber, an anion exchange membrane, a middle chamber, a cation exchange membrane, a cathode chamber, and a cathode. In the middle chamber, saltwater or seawater is desalinated by photoelectrochemical electrodialysis. Chloride ions are generated during the desalination, transferred to the anode chamber, and activated by the photoanode. In the anode chamber, wastewater is treated by the activated chloride ions. In the cathode chamber, at least one chemical species selected from the group consisting of water, oxygen, and carbon dioxide is reduced by electrons supplied from the photoanode.

A desalination battery includes a container configured to contain a saline water solution having a first concentration c.sub.1 of dissolved salts; first and second intercalation hosts, arranged to be in fluid communication with the saline water solution, at least the first intercalation host including expanded graphite having a plurality of graphene layers with an interlayer spacing between the graphene layers in z-direction greater than 0.34 nm; and a power source configured to supply electric current to the first and second intercalation hosts such that the first and second intercalation hosts reversibly store and release cations and anions from the saline water solution located between the plurality of graphene layers to generate a fresh water solution having a second concentration c.sub.2 of dissolved salts and a brine solution having a third concentration c.sub.3 of dissolved salts within the container such that c.sub.3>c.sub.1>c.sub.2.

The systems and methods described herein relate to use of a reverse diffusion system for removal of dissolved ions from a fluid, for example, salt ions. Specific embodiments include a system for desalinating salt water to produce potable water. The systems and methods can include pulsing low levels of electricity via electrodes in a scrolling pattern, so as to sweep the ions across a unit.

A device (10) for capacitive deionization of an aqueous media containing dissolved ion species, said device comprising a cell with a first primary electrode (2) and a second primary electrode (3) arranged opposite the first primary electrode (2) and preferably separated by at least one non-conductive spacer (4, 4). A third electrode (7) is arranged between the first and the second electrode. The third electrode (7) is grounded whereas the first and the second electrodes are polarized versus the grounded third electrode.

A low energy water treatment system and method is provided. The system has at least one electrodialysis device that produces partially treated water and a brine byproduct, a softener, and at least one electrodeionization device. The partially treated water stream can be softened by the softener to reduce the likelihood of scale formation and to reduce energy consumption in the electrodeionization device, which produces water having target properties. At least a portion of the energy used by the electrodeionization device can be generated by concentration differences between the brine and seawater streams introduced into compartments thereof. The brine stream can also be used to regenerate the softener.

The present disclosure provides a device comprising or configured to comprise composite resin electrodes. Further provided are methods of using the device for selectively removing dissolved ions from water.

Photochemical energy conversion is more efficient when a single light-absorbing unit is split into multiple light-absorbing units (N) that are each 1/N as thick as the single light-absorbing unit and thus use the same amount of material as the single light-absorbing unit. For electrocatalytic parameters relevant to water electrolysis, the maximum efficiency for solar-to-fuel conversion from a 1.75 eV bandgap material increases from approximately 1% for a single light-absorbing unit to greater than 20% for 128 identical stacked light-absorbing units. Alterations in utilization of photons results in a better match of the light-absorber power output to the load of the chemical transformation and in the case of high-quality light-absorbers there is an added benefit from radiative coupling between the light-absorbing units via photon recycling.

A device for removing chloride-containing salts from water includes a container configured to contain saline water, a first electrode arranged in fluid communication with the saline water, and a power source. The first electrode includes a conversion material that is substantially insoluble in the saline water and has a composition that includes at least two or more of aluminum, chlorine, copper, iron, oxygen, and potassium. The composition varies over a range with respect to a quantity of chloride ions per formula unit. The power source supplies current to the first electrode in a first operating state so as to induce a reversible conversion reaction in which the conversion material bonds to the chloride ions in the saline water to generate a treated water solution. The conversion material dissociates the chloride ions therefrom into the saline water solution in a second operating state to generate a wastewater solution.

A desalination battery includes a first electrode, a second electrode, an intercalation compound contained in the first electrode, a container configured to contain a saline water solution, and a power source. The intercalation compound includes at least one of a metal oxide, a metalloid oxide, a metal oxychloride, a metalloid oxychloride, and a hydrate thereof with each having a ternary or higher order. The first and second electrodes are configured to be arranged in fluid communication with the saline water solution. The power source is configured to supply electric current to the first and second electrodes in different operating states to induce a reversible intercalation reaction within the intercalation compound. The intercalation compound reversibly stores and releases target anions from the saline water solution to generate a fresh water solution in one operating state and a wastewater solution in another operating state.

A method for fabricating a porous carbon material possessing a hierarchical porosity, the method comprising subjecting a precursor composition to a curing step followed by a carbonization step, the precursor composition comprising: (i) a templating component comprised of a block copolymer, (ii) a phenolic component, (iii) a dione component in which carbonyl groups are adjacent, and (iv) an acidic component, wherein said carbonization step comprises heating the precursor composition at a carbonizing temperature for sufficient time to convert the precursor composition to a carbon material possessing a hierarchical porosity comprised of mesopores and macropores. Also described are the resulting hierarchical porous carbon material, a capacitive deionization device in which the porous carbon material is incorporated, as well as methods for desalinating water by use of said capacitive deionization device.