Journal of Colloid and Interface Science, Год журнала: 2025, Номер unknown
Опубликована: Янв. 1, 2025
Язык: Английский
The Innovation Materials, Год журнала: 2025, Номер unknown, С. 100116 - 100116
Опубликована: Янв. 1, 2025
<p>Significant volumes of lean methane (0.1–1.0 vol%) are released untreated into the atmosphere during industrial operations, contributing to greenhouse effect and energy wastage. Catalytic combustion presents a promising avenue mitigate these emissions. Depending on their active components, catalytic systems predominantly categorized noble metal-based non-noble catalysts, with palladium (Pd)-based catalysts recognized for superior low-temperature oxidation activity. Nevertheless, enhancing thermal stability Pd remains challenging, complicated by impurities such as H<sub>2</sub>O, SO<sub>2</sub> H<sub>2</sub>S in stream, which can cause catalyst poisoning deactivation. Recent research has focused design Pd-based bimetallic offering improved stability, activity, resistance harsh conditions. This review examines advancements improving deactivation combustion, covering site characterization, dispersion metal-support interactions, role auxiliary metals, structural modulation strategies. It also investigates impact environments performance, focusing mechanisms mitigation Ultimately, this identifies current trends challenges demanding applications. By providing insights enhanced poisoning, aims guide development that meet demands.</p>
Язык: Английский
Процитировано
4
Applied Catalysis A General, Год журнала: 2022, Номер 633, С. 118534 - 118534
Опубликована: Фев. 9, 2022
Язык: Английский
Процитировано
52
Chemical Engineering Journal, Год журнала: 2022, Номер 451, С. 138930 - 138930
Опубликована: Сен. 2, 2022
Язык: Английский
Процитировано
42
ACS Catalysis, Год журнала: 2023, Номер 14(1), С. 183 - 191
Опубликована: Дек. 13, 2023
Reducing methane emissions is crucial for mitigating global warming. Developing highly efficient catalysts low-temperature combustion of great importance. Supported single-atom (SACs) have received significant attention in this regard. However, their long-term stability and activity remain challenging. In study, we present a method creating active thermally stable Pd1/CeO2 catalyst by using thermal-shock synthesis (Pd1/CeO2-TS). By subjecting isolated Pd2+ ions to ultrafast shockwaves, control local environment, resulting unique electronic structures the geometry Pd single atoms. Compared with formed through atom trapping (Pd1/CeO2-AT), Pd1/CeO2-TS showed improved nearly 20-fold increase turnover frequency reversible against water. This attributed presence coordination-unsaturated Pd–O species surface hydroxyls on ceria. These factors enhance oxygen reduce barrier C–H bond activation, increased catalytic performance.
Язык: Английский
Процитировано
33
Chemical Engineering Journal, Год журнала: 2024, Номер 485, С. 149487 - 149487
Опубликована: Фев. 22, 2024
Язык: Английский
Процитировано
11
ACS Catalysis, Год журнала: 2021, Номер 11(21), С. 13066 - 13076
Опубликована: Окт. 13, 2021
Palladium (Pd)/zeolite-based catalysts have shown great promise in low-temperature CH4 oxidation reactions. However, improving the performance of Pd/zeolite while simultaneously decreasing Pd usage remains a challenge. Herein, we demonstrate that incorporation cobalt (Co) into 0.5 wt % Pd/BEA (Pd (0.5)/BEA) can substantially boost performance. In particular, increasing Co loading from 0 to 1 led continuous improvement activity, with T50 (temperature at which 50% conversion is achieved) >500 °C over (0.5)/BEA 352 Pd(0.5)Co(1.0)/BEA. Moreover, reaction rate Pd(0.5)Co(1.0)/BEA 250 was 77% greater than Pd(1.0)/BEA. Experimental evidence CH4-temperature programmed reduction, CO diffuse reflectance infrared Fourier transform spectroscopy, H2-temperature O2-temperature desorption, high-angle annular dark field-scanning transmission electron microscopy, energy-dispersive X-ray and apparent activation energy studies suggested promotion effect attributed formation highly active PdO, instead less ionic Pd. Stability tests showed comparable activity Pd(1.0)/BEA slightly improved H2O resistance. Density functional theory calculations revealed more stable ion-exchange sites (Al sites) BEA zeolites. being leads fewer available for thus but PdO nanocluster bimetallic PdCo/BEA catalysts.
Язык: Английский
Процитировано
43
Angewandte Chemie International Edition, Год журнала: 2022, Номер 62(5)
Опубликована: Дек. 7, 2022
Supported Pd single atom catalysts (SACs) have triggered great research interest in methane combustion yet with contradicting views on their activity and stability. Here, we show that the SAs can take different electronic structure atomic geometry ceria support, resulting catalytic properties. By a simple thermal pretreatment to prior deposition, unique anchoring site is created. The SA, taking this site, be activated Pdδ+ (0<δ<2) has greatly enhanced for oxidation: T50 lowered by up 130 °C almost 10 times higher turnover frequency compared untreated catalyst. of related its oxygen-deficient local elongated interacting distance ceria, leading capability delivering reactive oxygen species decomposing reaction intermediates. This work provides insights into designing highly efficient SACs oxidation reactions.
Язык: Английский
Процитировано
34
The Journal of Physical Chemistry C, Год журнала: 2022, Номер 126(3), С. 1439 - 1449
Опубликована: Янв. 14, 2022
Pd-ion-exchanged zeolites have emerged as promising materials for the adsorption and oxidation of air pollutants. For low-temperature vehicle exhaust, dispersed Pd ions can adsorb NOx even in H2O-rich exhaust containing carbon monoxide. To understand this phenomenon, changes ligand environment to be monitored situ. Herein, we directly observe activation hydrated ion shielded by H2O into a carbonyl–nitrosyl complex Pd2+(NO)(CO) SSZ-13 zeolite. The subsequent thermal desorption ligands on proceeds nitrosyl Pd2+ rather than carbonyl under various conditions. Thus, CO molecules act additional provide an alternative pathway with lower energy barrier accelerating NO through complex. We further demonstrate that hydration zeolite is prerequisite CO-induced reduction metallic Pd. limited dry conditions at temperatures high 500 °C, while water makes it possible near RT. However, primary sites are gases water. These findings clarify mechanistic aspects passive (PNA) process will help extend chemistry zeolite-based adsorbers practical applications.
Язык: Английский
Процитировано
30
Accounts of Chemical Research, Год журнала: 2023, Номер 57(1), С. 23 - 36
Опубликована: Дек. 15, 2023
ConspectusMethane complete oxidation is an important reaction that part of the general scheme used for removing pollutants contained in emissions from internal combustion engines and, more generally, processes. It has also recently attracted interest as option removal atmospheric methane context negative emission technologies. Methane, a powerful greenhouse gas, can be converted to carbon dioxide and water via its oxidation. Despite burning being facile because sustains after ignition, strong C–H bonds require catalyst perform at low temperatures absence flame so avoid formation nitrogen oxides, such those produced flares. This process allows obtained under conditions usually lead higher emissions, cold start case engines. Among several options include homo- heterogeneous catalysts, supported palladium-based catalysts are most active systems this reaction. Finely divided palladium activate 150 °C, although conversion not reached until 400–500 °C practical applications. Major goals achieve catalytic possible temperature utilize expensive metal efficiently.Compared any other transition metal, oxides orders magnitude reactive water. During last few decades, much research been devoted unveiling origin high activity their phase, effect support, promoters, defects, with goal further improving reactivity. There overall agreement trends, yet there noticeable differences some details performance palladium, including phase reasons deactivation poisoning. In Account we summarize our work space using well-defined especially model surfaces prepared colloidal nanocrystals precursors, spectroscopic tools unveil about chemistry catalysts. We describe advanced techniques aimed elucidating role parameters well engineering through advancing fundamental understanding synthesis methods. report state on phases sites, then move supports finally discuss stability phase. Overall, want emphasize importance designing realizing stable example variety energy environmental applications nanomaterials catalysis.
Язык: Английский
Процитировано
23
Fuel, Год журнала: 2023, Номер 340, С. 127493 - 127493
Опубликована: Янв. 19, 2023
Язык: Английский
Процитировано
20