摘要:
A vehicle exhaust system is provided and comprises a catalyst positioned in an exhaust passage of a vehicle. The catalyst is in the form of a washcoat supported on a substrate. The system includes a phase change material located adjacent to the catalyst to maintain the temperature of the catalyst between engine shut-down and subsequent start-up as well as to regulate the temperature during engine operation. In some embodiments, the phase change material comprises particles of a metal or metal alloy encapsulated in a ceramic material. The metal or metal alloy is adapted to have a phase change that occurs within a temperature range wherein the catalyst is active.
摘要:
A vehicle exhaust system is provided and comprises a catalyst positioned in an exhaust passage of a vehicle. The catalyst is in the form of a washcoat supported on a substrate. The system includes a phase change material located adjacent to the catalyst to maintain the temperature of the catalyst between engine shut-down and subsequent start-up as well as to regulate the temperature during engine operation. In some embodiments, the phase change material comprises particles of a metal or metal alloy encapsulated in a ceramic material. The metal or metal alloy is adapted to have a phase change that occurs within a temperature range wherein the catalyst is active.
摘要:
A vehicle exhaust system is provided and comprises a catalyst positioned in an exhaust passage of a vehicle. The catalyst is in the form of a washcoat supported on a substrate. The system includes a phase change material located adjacent to the catalyst to maintain the temperature of the catalyst between engine shut-down and subsequent start-up as well as to regulate the temperature during engine operation. In some embodiments, the phase change material comprises particles of a metal or metal alloy encapsulated in a ceramic material. The metal or metal alloy is adapted to have a phase change that occurs within a temperature range wherein the catalyst is active.
摘要:
A vehicle exhaust system is provided and comprises a catalyst positioned in an exhaust passage of a vehicle. The catalyst is in the form of a washcoat supported on a substrate. The system includes a phase change material located adjacent to the catalyst to maintain the temperature of the catalyst between engine shut-down and subsequent start-up as well as to regulate the temperature during engine operation. In some embodiments, the phase change material comprises particles of a metal or metal alloy encapsulated in a ceramic material. The metal or metal alloy is adapted to have a phase change that occurs within a temperature range wherein the catalyst is active.
摘要:
In at least one embodiment, an oxygen reduction reaction catalyst (ORR) and a method for making the catalyst are provided. The method may include depositing a metal oxide on a graphitized carbon or graphene substrate. A platinum catalyst may then be deposited over the metal oxide to provide an ORR catalyst for use in, for example, a PEMFC. The metal oxide may be niobium oxide and may have an amorphous structure. The platinum catalyst may form a thin, electrically interconnected network structure overlaying the metal oxide. The ORR catalyst may be prepared by alternating the deposition of the metal oxide and the platinum catalyst, for example, using physical vapor deposition. The ORR catalyst may have a specific activity of at least 1,000 μA/cm2 Pt and may approach or achieve bulk Pt activity.
摘要翻译:在至少一个实施方案中,提供氧还原反应催化剂(ORR)和制备催化剂的方法。 该方法可以包括在石墨化碳或石墨烯衬底上沉积金属氧化物。 然后可以在金属氧化物上沉积铂催化剂以提供用于例如PEMFC的ORR催化剂。 金属氧化物可以是氧化铌,并且可以具有无定形结构。 铂催化剂可以形成覆盖金属氧化物的薄的,电互连的网络结构。 可以通过例如使用物理气相沉积交替沉积金属氧化物和铂催化剂来制备ORR催化剂。 ORR催化剂可以具有至少1,000μA/ cm 2 Pt的比活性,并且可以接近或实现体积Pt活性。
摘要:
A vehicle exhaust system is provided and comprises a catalyst positioned in an exhaust passage of a vehicle. The catalyst is in the form of a washcoat supported on a substrate. The system includes a phase change material located adjacent to the catalyst to maintain the temperature of the catalyst between engine shut-down and subsequent start-up as well as to regulate the temperature during engine operation. In some embodiments, the phase change material comprises particles of a metal or metal alloy encapsulated in a ceramic material. The metal or metal alloy is adapted to have a phase change that occurs within a temperature range wherein the catalyst is active.
摘要:
A fuel cell oxidation reduction reaction catalyst comprising a carbon substrate, an amorphous metal oxide intermediate layer on the substrate, and an intertwined matrix of platinum and elemental niobium arranged to form a surface metal layer covering the intermediate layer such that upon oxidation, the niobium binds with oxygen resulting in strengthened bonds between the platinum and the intermediate layer.
摘要:
Phosphorus tolerant or resistant three-way catalysts (TWC) are disclosed. The TWC may include a substrate defining a plurality of channels. It may include front and rear washcoat portions overlying the substrate and having respective first and second washcoat loadings, the first washcoat loading being at most 2.0 g/in3 and less than the second washcoat loading. The front washcoat portion may include a catalyst material supported on a support material comprising a cerium oxide, such as ceria or CZO, or a pre-phosphated material, such as AlPO4, or CePO4. In one embodiment, the support material may comprise at least 85 wt. % of a cerium oxide or at least 85 wt. % of a phosphate-containing material. The front portion and the underlying substrate may comprise from 3 to 25 vol. % of the three-way catalyst or the front portion may overly up to an initial 15% of an axial length of the substrate.
摘要:
A fuel cell oxidation reduction reaction catalyst comprising a carbon substrate, an amorphous metal oxide intermediate layer on the substrate, and an intertwined matrix of platinum and elemental niobium arranged to form a surface metal layer covering the intermediate layer such that upon oxidation, the niobium binds with oxygen resulting in strengthened bonds between the platinum and the intermediate layer.
摘要:
A vehicle exhaust system is provided and comprises a catalyst positioned in an exhaust passage of a vehicle. The catalyst is in the form of a washcoat supported on a substrate. The system includes a phase change material located adjacent to the catalyst to maintain the temperature of the catalyst between engine shut-down and subsequent start-up as well as to regulate the temperature during engine operation. In some embodiments, the phase change material comprises particles of a metal or metal alloy encapsulated in a ceramic material. The metal or metal alloy is adapted to have a phase change that occurs within a temperature range wherein the catalyst is active.