The invention discloses a nitrogen-doped mesoporous carbon-coated Titanium dioxide composite photocatalyst, a preparation method and use thereof. The preparation method comprises the steps of: dissolving an organic ligand and Ti(OC.sub.3H.sub.7).sub.4 in a mixture of methanol and DMF at a certain ratio, performing a hydrothermal reaction, centrifuging and drying to obtain a Titanium-based metal organic framework (Ti-MOF); pyrolyzing the obtained Ti-MOF under an inert atmosphere, and oxidizing the same for etching to obtain a nitrogen-doped mesoporous carbon-coated Titanium dioxide composite photocatalyst. The obtained composite photocatalyst not only facilitates the adsorption, enrichment and mass transfer of low concentration VOCs, but also efficiently degrades VOCs under sunlight. It has high degradation activity and stability when performing photocatalytic removal of VOCs in the presence of visible light, is simple in synthesis, low in preparation cost, and has strong potential for the use in environmental protection.

Certain embodiments of the invention are directed to nitrogen rich three dimensional C.sub.3N.sub.4+ mesoporous graphitic carbon nitride (gMCN) material formed from diaminoguanidine precursors, the gMCN having a spherical morphology and an average monomodal pore diameter between 6.5 to 9.5 nm.

A bipolar membrane comprising a cation exchange mat of one or more cation exchange polymers, an anion exchange mat of one or more anion exchange polymers, and an internal 3D bipolar interface, disposed between the cation and anion exchange layers, including a mixture of at least one cation exchange polymer and at least one anion exchange polymer, such that an interface of the at least one cation exchange polymer and the at least one anion exchange polymer is the internal 3D bipolar interface that has a large area, and the at least one cation exchange polymer in the 3D bipolar interface is connected to the one or more cation exchange polymers of the cation exchange layer, and the at least one anion exchange polymer in the 3D bipolar interface is connected to the one or more anion exchange polymers of the anion exchange layer.

In an air cleaner, a cassette is removably installed in an air cleaner housing. The cassette holds therein a filter formed by stacking a chemical filter and an air cleaner element. At the time of replacement or inspection of the filter, the cassette is pulled out of the air cleaner housing, and then the filter is removed from the cassette. Further, after completion of the replacement or inspection, the filter is placed in the cassette, and the cassette is installed in the air cleaner housing.

A compact, lightweight, low power aircraft air filtration and VOC removal unit enables the removal of VOCs from cabin air in a passenger aircraft. A plurality of baffles having air flow-through airflow spaces are spaced apart along a duct. UV LEDs are mounted on the interior sides of the outermost baffles, and on both sides of all interior baffles. A filter module is disposed between pairs of baffles, and spaced from the baffles sufficiently to illuminate the entirety of both sides. Each filter modules comprises a plurality of filters. The filters are selected from a coarse foam, a fine foam, or a fused quartz filament felt. Each filter is loaded with a catalyst including one or more of AEROXIDE® P25, other pure titanium dioxide (TiO.sub.2), iron-doped TiO.sub.2, carbon-doped TiO.sub.2, and combinations thereof. The catalysts on the filters, under UV illumination, chemically reduce VOCs in the airflow to non-VOC molecules.

Systems and methods for treating automotive vehicle emissions on board an automotive vehicle include the use of waste heat recovery, electrochemical water splitting, phototcatalytic water splitting, and selective catalytic reduction. Waste heat recovery is used to power electrochemical water splitting, or photocatalytic water splitting. Photons collected from a solar panel are used in photocatalytic water splitting, or in photo-assisted selective catalytic reduction. Hydrogen gas generated by water splitting is used in conjunction with catalytic reduction units to catalytically reduce NOx in an engine exhaust gas.

In some aspects and embodiments, the present application provides a wide range of porous 1-D polymeric graphitic carbon-nitride materials that are atomically doped with binary metals in different morphologies. In some embodiments, the graphitic carbon-nitride materials can be prepared with high mass production from inexpensive and natural abundant precursors. In some embodiments, the materials were used successfully for the oxidation of CO to CO.sub.2 under ambient reaction temperature in addition to the reduction of CO.sub.2 into hydrocarbons. In some embodiments, the materials can be used for practical and large-scale gas conversion for household or industrial applications.

An emission control device for a vehicle, which includes an open cell carbon foam substrate having a geometric surface area of at least about 5000 m.sup.2/m.sup.3, wherein the substrate has a catalytic metal.

A porous carbon material composite formed of a porous carbon material and a functional material and equipped with high functionality. The porous carbon material composite is formed of (A) a porous carbon material obtainable from a plant-derived material having a silicon (Si) content of 5 wt % or higher as a raw material; and (B) a functional material adhered on the porous carbon material, and has a specific surface area of 10 m.sup.2/g or greater as determined by the nitrogen BET method and a pore volume of 0.1 cm.sup.3/g or greater as determined by the BJH method and MP method.

An emission control device for a vehicle, which includes an open cell carbon foam substrate having a geometric surface area of at least about 5000 m.sup.2/m.sup.3, wherein the substrate has a catalytic metal.