Microporous and Mesoporous Materials最新文献_第5页

Adsorption performance and mechanism of single-component and multi-component VOCs by Beta zeolites with different Si/Al ratios 不同硅/铝比 Beta 沸石对单组分和多组分挥发性有机化合物的吸附性能和机理

IF 4.8 3区材料科学 Q1 CHEMISTRY, APPLIED

Microporous and Mesoporous Materials

Pub Date : 2024-10-09 DOI: 10.1016/j.micromeso.2024.113365

Daiqiang Li , Xueli Guo , Lian Wang , Hua Deng , Zhilin Zhang , Jinzhu Ma , Hong He

The physical and chemical properties of VOCs and zeolite materials generally affect adsorption efficacy for VOCs removal. Here, toluene and methanol were chosen as typical VOCs with different polarities and molecular diameters to investigate the performance and mechanism of their adsorption on Beta zeolites with various Si/Al ratios. It was found that high-silica Beta exhibited superior toluene adsorption capacity, while low-silica Beta showed higher methanol adsorption capacity. Compared with single-component adsorption, in the case of co-adsorption of toluene and methanol, the saturation adsorption capacities for toluene and methanol only changed slightly even with the existence of competitive adsorption and weakened adsorption strength. Importantly, there was almost no decrease in absorption capacity after 10 repeated adsorption-regeneration cycles, showing the excellent reusability of Beta zeolites for toluene and methanol removal. Whether on low-silica or high-silica Beta, physical adsorption of toluene and methanol was dominant, along with a small proportion of chemical adsorption on low-silica Beta based on acid sites. Similar size between the diameters of toluene and the pore channels of Beta zeolites was responsible for strong adsorption force, increase of adsorption capacity, and minor effect on absorption performance in the process of competitive adsorption. Strong interaction between acid sites and polar methanol through H-bond or non-polar toluene by electrostatic attraction promoted chemical adsorption. Furthermore, toluene and methanol both tended to absorb in the twelve-membered-ring of Beta zeolites on Si-OH-Al, Al-OH, and Si-OH sites. This study provides insight into the factors influencing the adsorption performance and mechanism of toluene and methanol on zeolites, which gives potential guidance for the selection of adsorbents for high-efficiency VOCs removal.

挥发性有机化合物和沸石材料的物理和化学特性通常会影响对挥发性有机化合物的吸附去除效果。本文选择甲苯和甲醇作为具有不同极性和分子直径的典型挥发性有机化合物，研究它们在不同硅/铝比例的 Beta 沸石上的吸附性能和机理。研究发现，高硅 Beta 具有更强的甲苯吸附能力，而低硅 Beta 则具有更强的甲醇吸附能力。与单组分吸附相比，在甲苯和甲醇共吸附的情况下，即使存在竞争吸附和吸附强度减弱的情况，甲苯和甲醇的饱和吸附容量也只是略有变化。重要的是，经过 10 次重复吸附-再生循环后，吸附容量几乎没有下降，这表明 Beta 沸石在去除甲苯和甲醇方面具有极佳的重复使用性。无论是在低硅还是高硅 Beta 上，甲苯和甲醇的物理吸附都占主导地位，而在低硅 Beta 上，基于酸性位点的化学吸附只占一小部分。在竞争吸附过程中，甲苯直径与 Beta 沸石孔道直径相近，因此吸附力强，吸附容量增大，而对吸附性能的影响较小。酸性位点通过 H 键与极性甲醇或通过静电吸引与非极性甲苯之间的强相互作用促进了化学吸附。此外，甲苯和甲醇都倾向于在 Beta 沸石的 Si-OH-Al、Al-OH 和 Si-OH 位点上的十二元环中吸附。这项研究深入探讨了沸石对甲苯和甲醇的吸附性能和机理的影响因素，为高效去除挥发性有机化合物的吸附剂选择提供了潜在的指导。

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引用次数: 0

Tuning the atomic ordering of AFI framework with templates charge 用模板电荷调整 AFI 框架的原子排序

IF 4.8 3区材料科学 Q1 CHEMISTRY, APPLIED

Microporous and Mesoporous Materials

Pub Date : 2024-10-05 DOI: 10.1016/j.micromeso.2024.113339

Eddy Dib , Ludovica Pace , Vincent Sarou-Kanian , Francesco Dalena , Diogenes Honorato-Piva , Svetlana Mintova

In this work, AlPO₄-5 (AFI) zeotype materials were synthesized using the microwave approach in the presence of two organic templates i.e. tripropylamine (R) and tetrapropylammonium (R⁺). The long- and short-range crystalline order of the samples were investigated by considering the effect of the template's charge on the atomic-level ordering of the AFI framework. Using advanced NMR spectroscopy, we shed the light on the importance of templates' role on the organization of the inorganic framework of aluminophosphates. The spectroscopic data clearly show a wider distribution of Al and P environments in the materials synthesized with the charged template (R⁺) due to the need of hydroxyl groups charge compensators that induce some bridges distortions. When a charged molecule (R⁺) was used, aluminum appears to be responsible for the charge compensation mechanism via the association of OH groups, impacting the environment of phosphorus as well. The hydroxyl groups needed for charge compensation in samples synthesized with R⁺ persist after calcination. Consequently, the hydrophilicity of the sample synthesized with R⁺ features approximatively two times higher values compared to the one synthesized with R.

本研究采用微波方法，在三丙胺（R）和四丙胺（R+）两种有机模板的存在下合成了 AlPO4-5（AFI）沸石材料。通过考虑模板电荷对 AFI 框架原子级有序的影响，研究了样品的长程和短程晶序。利用先进的核磁共振光谱，我们揭示了模板对铝磷酸盐无机框架组织的重要作用。光谱数据清楚地表明，由于需要羟基电荷补偿器来诱导一些桥梁畸变，在使用带电模板（R+）合成的材料中，Al 和 P 的环境分布更广。当使用带电分子（R+）时，铝似乎通过羟基的结合负责电荷补偿机制，这也影响了磷的环境。在使用 R+ 合成的样品中，电荷补偿所需的羟基在煅烧后仍然存在。因此，与用 R 合成的样品相比，用 R+ 合成的样品的亲水性大约高出两倍。

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引用次数: 0

MOR-to-MFI interzeolite transformations: Tuning of paired sites content towards the development of efficient MTH catalyst MOR-MFI沸石间转化：调整配对位点含量以开发高效的 MTH 催化剂

IF 4.8 3区材料科学 Q1 CHEMISTRY, APPLIED

Microporous and Mesoporous Materials

Pub Date : 2024-10-05 DOI: 10.1016/j.micromeso.2024.113364

Daniil V. Bruter , Vladimir S. Pavlov , Irina I. Ivanova

Interzeolite transformation is a rapidly developing method of zeolite synthesis, which allows a precise design of the active site structure. We report on the application of MOR to MFI interzeolite transformation (IZT) for the preparation of MFI zeolite with variable content of paired sites and the elucidation of their role in the MTH reaction. IZT procedure involved hydrothermal treatment of the reaction mixture containing mordenite zeolite as a source of silica and alumina, alkali, TPAOH, TPABr and water. Tuning of paired sites was achieved by variation of the content of water and alkali in the reaction mixture and the application of seeding. The results demonstrate that IZT procedure allows to tune paired sites content within 10–65 % without affecting other characteristics of MFI products, such as Si/Al ratio, crystal size, texture, acid sites type, content and strength, as well as the amount of EFAL species and the distribution of aluminum between channels and intersections of the MFI structure. The evaluation of MOR-to-MFI zeolites with different paired sites content in the MTH reaction pointed to significant effect of paired sites on the stability of catalytic activity with time on stream and on the propylene/ethylene selectivity.

沸石间转化是一种快速发展的沸石合成方法，可以精确设计活性位点结构。我们报告了将 MOR 应用于 MFI 沸石间转化（IZT）以制备配对位点含量可变的 MFI 沸石，并阐明其在 MTH 反应中的作用。IZT 过程包括对含有作为二氧化硅和氧化铝来源的莫来石沸石、碱、TPAOH、TPABr 和水的反应混合物进行水热处理。通过改变反应混合物中水和碱的含量以及播种的应用，实现了配对位点的调整。结果表明，IZT 程序可将配对位点的含量调整在 10-65 % 的范围内，而不会影响 MFI 产品的其他特性，如硅/铝比、晶体尺寸、质地、酸位点类型、含量和强度，以及 EFAL 种类的数量和铝在 MFI 结构的通道和交叉点之间的分布。在 MTH 反应中对具有不同配对位点含量的 MOR 转 MFI 沸石进行的评估表明，配对位点对催化活性随时间流的稳定性以及对丙烯/乙烯选择性有显著影响。

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引用次数: 0

A nanoscale investigation of the formation of mesostructured zeolites FAU and LTL 介观结构沸石形成的纳米级研究 FAU 和 LTL

IF 4.8 3区材料科学 Q1 CHEMISTRY, APPLIED

Microporous and Mesoporous Materials

Pub Date : 2024-10-05 DOI: 10.1016/j.micromeso.2024.113363

Vladimir Zholobenko , Martin Hollamby , Aqeel Al-Ani , Oleg I. Lebedev , Andrew J. Smith , Tim Snow

Nanostructured materials can be utilised as potential catalysts for the production of platform chemicals and renewable biofuels from biomass derived molecules. The formation of hierarchical meso-microporous zeolites LTL and FAU via the surfactant assisted tandem acid-base post-synthesis treatment has been investigated by time-resolved in situ synchrotron SAXS and WAXS, providing a new insight into the mechanism of the mesostructuring treatment. Based on the results of TEM and in situ synchrotron measurements, a model for the formation of the core-shell structure of LTL zeolite crystals is proposed. Complementary evaluation using FTIR, NMR and nitrogen adsorption, in conjunction with reaction studies on mesostructured zeolites, demonstrated a potential for enhanced catalytic performance of these materials owing to the increased accessibility of the active sites and reduced transport limitations.

纳米结构材料可作为潜在的催化剂，用于从生物质衍生分子中生产平台化学品和可再生生物燃料。我们利用时间分辨原位同步辐射光散射和扫描电镜分析法（SAXS）和原位同步辐射光散射和扫描电镜分析法（WAXS）研究了通过表面活性剂辅助串联酸碱合成后处理形成分层介微孔沸石 LTL 和 FAU 的过程，从而对介结构处理的机理有了新的认识。根据 TEM 和原位同步辐射测量的结果，提出了 LTL 沸石晶体核壳结构的形成模型。利用傅立叶变换红外光谱、核磁共振和氮吸附进行的补充评估，以及对介观结构沸石进行的反应研究表明，由于活性位点的可及性增加，传输限制减少，这些材料具有提高催化性能的潜力。

引用次数: 0

Microwave-assisted synthesis of solketal from glycerol and acetone in the presence of SAPO-34 and SAPO-5 在 SAPO-34 和 SAPO-5 的存在下，微波辅助从甘油和丙酮合成溶酮醛

IF 4.8 3区材料科学 Q1 CHEMISTRY, APPLIED

Microporous and Mesoporous Materials

Pub Date : 2024-10-05 DOI: 10.1016/j.micromeso.2024.113361

Anna S. Makova , Valentina N. Panchenko , Vasilii A. Bolotov , Nikolai A. Davshan , Igor V. Mishin , Maria N. Timofeeva , Kristina I. Shefer , Marina Ter-Akopyan , Leonid M. Kustov , Sung Hwa Jhung

Solketal is one of the most promising additives improving the properties of motor fuels. Investigations related to process intensification of synthesis of solketal from glycerol and acetone is gaining importance. The present work illustrates the use of the microwave mode for intensification of this process in the presence of silicoaluminophosphates (SAPO) as catalysts. The main focus of the study was placed on tuning the textural, acidic, and catalytic properties of SAPO-34 and SAPO-5 via variation of the synthesis parameters, such as the nature of Al and Si sources and the structure-directing agent. The catalytic properties of SAPO materials were investigated in the synthesis of solketal from glycerol and acetone under microwave assistance at the acetone/glycerol molar ratio of 2.4 in a methanol solution (glycerol/methanol: 1 g/1 mL) and 56 °C. It was demonstrated that the selectivity towards solketal was 91.1–98.6 % in the presence of the studied materials. The activities of mesoporous SAPO-34 and SAPO-5 prepared in the presence of triethylamine were higher as compared with microporous SAPO-34 prepared in the presence of tetraethylammonium hydroxide due to the high mesoporosity and a larger content of acid sites. The 90.4 % conversion of glycerol and 98.6 % selectivity towards solketal were observed in the presence of mesoporous 7.6%SAPO-34 for 90 min. The advantage of using microwave technology is shown. The solketal yield in the reaction under microwave irradiation was 3 times higher than that in the process performed under thermal heating conditions.

Solketal 是一种最有前途的添加剂，可改善汽车燃料的性能。有关从甘油和丙酮合成 Solketal 的强化工艺的研究越来越重要。本研究说明了在有硅铝磷酸盐（SAPO）作为催化剂的情况下，利用微波模式强化该工艺的情况。研究的重点是通过改变合成参数，如铝源和硅源的性质以及结构引导剂，来调整 SAPO-34 和 SAPO-5 的质地、酸性和催化特性。在微波辅助下，在丙酮/甘油摩尔比为 2.4 的甲醇溶液（甘油/甲醇：1 克/1 毫升）中，温度为 56 °C，研究了 SAPO 材料从甘油和丙酮合成溶酮醛的催化特性。结果表明，在所研究材料的存在下，对 Solketal 的选择性为 91.1-98.6%。与在氢氧化四乙胺存在下制备的微孔 SAPO-34 相比，在三乙胺存在下制备的介孔 SAPO-34 和 SAPO-5 具有更高的活性，这是因为它们具有较高的介孔率和更多的酸位点。在介孔 7.6%SAPO-34 存在下 90 分钟，观察到甘油的转化率为 90.4%，对索酮醛的选择性为 98.6%。使用微波技术的优势显而易见。在微波辐照下进行的反应中，索酮醛的产量比在热加热条件下进行的反应高出 3 倍。

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引用次数: 0

High activity of cobalt-atomically dispersed catalyst on mesoporous carbon for rechargeable Zn-air batteries via effective removal of the hard template 通过有效去除硬模板实现介孔碳上钴原子分散催化剂的高活性，用于可充电锌-空气电池

IF 4.8 3区材料科学 Q1 CHEMISTRY, APPLIED

Microporous and Mesoporous Materials

Pub Date : 2024-10-04 DOI: 10.1016/j.micromeso.2024.113359

Yahreli Audeves−Audeves , Alejandro Arredondo−Espínola , Osvaldo Nava , Amelia Olivas , Julieta Torres-González , Lorena Álvarez‒Contreras , Minerva Guerra-Balcázar , Noé Arjona

The use of oxygen from air in Zn-air batteries requires the smart design of materials with bifunctional activity for oxygen reduction and evolution reactions (ORR/OER), and with a porous structure to facilitate the diffusion of oxygen gas to active sites. Kit-6 template-assisted porous structures have been proposed to this end; however, traditional methods for the removal of Kit-6 templates are highly aggressive and environmentally harmful. In this study, we present the synthesis of a cobalt atomically dispersed catalyst (Co-ADC) with interlayer engineering using mesoporous Kit−6 templates, focusing on two removal strategies: sodium hydroxide (0.5, 1, and 2 M) and hydrofluoric acid (15, 30, and 45 %). Physicochemical results indicated that Co-ADC-containing nanoparticles were obtained using the proposed methodology, while the use of HF promoted the loss of cobalt in the catalyst. During the activity evaluation for the ORR, and it was found that 0.5 M NaOH and HF at 15 % displayed similar activity, which could be related to the effect of carbon material as co-catalyst, but the first enabled a close 4e⁻ pathway, and thus, the Co-ADC presented a ΔE_OER-ORR of 640 mV. This optimized ADC displayed improved functionality owing to diffusion improvements by the mesoporous structure, presenting a maximum power density of 130.6 mW cm⁻² and 30 % higher specific activity than the Pt + IrO₂/C reference material. Rechargeability was evaluated, yielding a ΔV = 0.87 V at 5.175 mA cm⁻² with a round-trip efficiency of 57.5 %. Nonetheless, the optimized material presented higher rechargeability, displaying no significant round-trip changes after 100 cycles, while Pt + IrO₂/C presented changes due to OER issues after only 48 cycles.

要在锌-空气电池中使用空气中的氧气，就必须巧妙地设计出具有氧气还原和进化反应（ORR/OER）双功能活性的材料，并具有多孔结构，以促进氧气向活性位点扩散。为此，有人提出了 Kit-6 模板辅助多孔结构；然而，去除 Kit-6 模板的传统方法具有很强的侵蚀性，而且对环境有害。在本研究中，我们利用介孔 Kit-6 模板合成了一种具有层间工程的钴原子分散催化剂（Co-ADC），重点研究了两种去除策略：氢氧化钠（0.5、1 和 2 M）和氢氟酸（15、30 和 45 %）。理化结果表明，使用建议的方法可以获得含 Co-ADC 的纳米颗粒，而使用氢氟酸会导致催化剂中钴的流失。在对 ORR 进行活性评估时发现，0.5 M NaOH 和 HF（浓度为 15%）显示出相似的活性，这可能与作为助催化剂的碳材料的影响有关，但前者使 4e- 途径更为接近，因此 Co-ADC 的 ΔEOER-ORR 值为 640 mV。由于介孔结构改善了扩散，这种优化的 ADC 显示出更强的功能性，其最大功率密度为 130.6 mW cm-2，比 Pt + IrO2/C 参考材料的比活性高出 30%。对可充电性进行了评估，结果显示，在 5.175 mA cm-2 的条件下，ΔV = 0.87 V，往返效率为 57.5%。尽管如此，经过优化的材料具有更高的可充电性，在 100 次循环后没有出现明显的往返变化，而 Pt + IrO2/C 仅在 48 次循环后就因 OER 问题出现了变化。

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引用次数: 0

Synthesis of porous hypercrosslinked polymers from waste polystyrene for efficient CO2 separation 利用废聚苯乙烯合成多孔超交联聚合物，实现高效二氧化碳分离

IF 4.8 3区材料科学 Q1 CHEMISTRY, APPLIED

Microporous and Mesoporous Materials

Pub Date : 2024-10-04 DOI: 10.1016/j.micromeso.2024.113360

Yuanhao Wang , Lan Luo , Chunliang Yang , Quanlan Liao , Tianxiang Zhao

A series of porous hypercrosslinked polymers (HCP-x) were synthesized from waste polystyrene foam via Fridel-Crafts alkylation reaction, aiming to optimize the utilization of waste plastics. The impact of various crosslinkers on the structural characteristics and CO₂ adsorption properties of HCP-x was investigated. The results indicated that HCP-x polymers possess high specific surface areas spanning 830–1182 m² g⁻¹, abundant narrow micropores, and exceptional thermal stability. Notably, HCP-2 exhibited the highest CO₂ adsorption capacity of 2.77 mmol g⁻¹ at 273 K and 1.0 bar. These hypercrosslinked polymers also demonstrated a favorable CO₂/N₂ ideal selectivity and robust cyclic adsorption performance. Breakthrough experiments confirmed the selective adsorption of CO2 from simulated flue gas containing CO₂/N₂ (15/85). Additionally, the mechanism underlying CO₂ adsorption on HCP-x was elucidated by analyzing adsorption thermodynamics and diffusion kinetics. This study not only introduces an innovative method for recycling waste polystyrene foam but also underscores the potential of HCP-x as an effective adsorbent for CO₂ capture.

以废弃聚苯乙烯泡沫为原料，通过 Fridel-Crafts 烷基化反应合成了一系列多孔超交联聚合物（HCP-x），旨在优化废弃塑料的利用。研究了各种交联剂对 HCP-x 结构特征和二氧化碳吸附性能的影响。结果表明，HCP-x 聚合物具有 830-1182 m2 g-1 的高比表面积、丰富的狭窄微孔和优异的热稳定性。值得注意的是，HCP-2 在 273 K 和 1.0 bar 条件下的二氧化碳吸附容量最高，达到 2.77 mmol g-1。这些超交联聚合物还表现出良好的 CO2/N2 理想选择性和强大的循环吸附性能。突破性实验证实了从含有 CO2/N2 (15/85) 的模拟烟气中选择性吸附 CO2 的能力。此外，通过分析吸附热力学和扩散动力学，阐明了 HCP-x 吸附二氧化碳的机理。这项研究不仅介绍了一种回收利用废弃聚苯乙烯泡沫的创新方法，还强调了 HCP-x 作为一种有效的二氧化碳捕获吸附剂的潜力。

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引用次数: 0

Cu-trimesate and mesoporous silica composite as adsorbent showing enhanced CO2/CH4 and CO2/N2 selectivity for biogas and flue gas separation 铜-三酸铜和介孔二氧化硅复合吸附剂在沼气和烟气分离中显示出更高的 CO2/CH4 和 CO2/N2 选择性

IF 4.8 3区材料科学 Q1 CHEMISTRY, APPLIED

Microporous and Mesoporous Materials

Pub Date : 2024-10-02 DOI: 10.1016/j.micromeso.2024.113354

Suman Dalakoti , Narendra Singh , Anjali Sharma , Anjali Singh , Madhur Sachdeva , Swapnil Divekar , Aarti Arya , R. Surya Murali , Soumen Dasgupta

Due to their diverse structure, high porosity, and tunable functionality, Metal-Organic Frameworks (MOFs) hold great potential as materials for diverse applications, including gas separation. Material science researchers are focusing on creating flexible materials that have special properties. Most of the latest research mainly concentrates on fabricating composite materials of MOFs and other functional materials. These MOF-based composites can mitigate the limitations of pure MOFs and may even perform better than the individual components. Here, we present a systematic study on the effect of solvent in synthesising a composite (Cu-BTC@SBA-15) of Cu-trimesate MOF (aka CuBTC) and ordered mesoporous silica SBA-15, showing considerable improvement in selectivity for CO₂ adsorption from the flue gas and biogas. The pristine Cu-BTC, SBA-15 and the composites with different content of Cu-BTC were characterized by PXRD, BET, FT-IR, SEM, TEM and TGA techniques. The pure gas adsorption isotherms were measured for CO₂, CH₄, and N₂ gases. Ideal Adsorbed Solution Theory (IAST) is used for the binary selectivity calculations for gas systems such as CO₂/CH₄ and CO₂/N₂ in the context of biogas and flue gas separation. The composite exhibited an increase in CO₂/CH₄ selectivity by 39 % compared to pure Cu-BTC and 85 % compared to pure SBA-15. For the CO₂/N₂ system, the composite showed 38 % higher selectivity than Cu-BTC. The work has significance in the design of effective MOF-based composites for CO₂ separation. Our work might open up a new route to design multifunctional materials for worldwide applications through an adsorptive and or mixed matrix membrane route.

金属有机框架（MOFs）具有结构多样、孔隙率高和功能可调等特点，因此作为包括气体分离在内的多种应用材料具有巨大潜力。材料科学研究人员正致力于创造具有特殊性能的柔性材料。大多数最新研究主要集中在制造 MOF 和其他功能材料的复合材料上。这些基于 MOF 的复合材料可减轻纯 MOF 的局限性，其性能甚至可能优于单个成分。在此，我们系统研究了溶剂对合成铜-三酸盐 MOF（又称 CuBTC）和有序介孔二氧化硅 SBA-15 复合材料（Cu-BTC@SBA-15）的影响，结果表明，该复合材料对烟道气和沼气中 CO2 的吸附选择性有显著提高。原始 Cu-BTC、SBA-15 和不同 Cu-BTC 含量的复合材料通过 PXRD、BET、FT-IR、SEM、TEM 和 TGA 技术进行了表征。测量了 CO2、CH4 和 N2 气体的纯气体吸附等温线。理想吸附溶液理论（IAST）被用于计算沼气和烟气分离中 CO2/CH4 和 CO2/N2 等气体系统的二元选择性。与纯 Cu-BTC 相比，复合材料的 CO2/CH4 选择性提高了 39%，与纯 SBA-15 相比，提高了 85%。在 CO2/N2 系统中，复合材料的选择性比 Cu-BTC 高 38%。这项工作对于设计有效的基于 MOF 的复合材料用于二氧化碳分离具有重要意义。我们的工作可能会开辟一条新的途径，通过吸附膜或混合基质膜途径设计出多功能材料，应用于全球范围。

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引用次数: 0

One-pot synthesis of Ir subnanosized clusters supported on MWW nanosheets as effective catalysts for C-C bond hydrogenolysis 以 MWW 纳米片为支撑的 Ir 亚纳米化团簇的单锅合成，作为 C-C 键氢解的有效催化剂

IF 4.8 3区材料科学 Q1 CHEMISTRY, APPLIED

Microporous and Mesoporous Materials

Pub Date : 2024-10-01 DOI: 10.1016/j.micromeso.2024.113356

Evgeny Naranov , Alexey Sadovnikov , Olga Arapova , Dmitry Gorbunov , Alexander Gorbunov , Svetlana Shapovalova , Alexander Guda , Alexander Soldatov , Anton Maximov

The rational design synthesis of metal catalysts with high dispersion and ordered structure is a challenging subject in materials chemistry and heterogeneous catalysis. In this study, we report one-pot synthesis of Ir subnanosized particles supported on MWW nanosheets and their application in hydrogenolysis of decalin. Here, it has been found that C-C bond cleavage occurs via a synergistic carbocation and carbene mechanism on Ir-containing catalysts, and via carbocation in the case of solid acids. The combination of optimal acidic and metallic site characteristics in the subnanosized Ir supported on MWW nanosheets Pill_Ir-ZN_150 sample contributes to the high activity of the final catalysts. We expect that these Ir catalytic systems will open up more opportunities for hydrogenolysis of naphthenics to high-value products.

合理设计合成具有高分散性和有序结构的金属催化剂是材料化学和异相催化领域的一个挑战性课题。在本研究中，我们报告了在 MWW 纳米片上支撑的亚纳米化 Ir 粒子的一锅合成及其在癸醛氢解中的应用。研究发现，在含 Ir 的催化剂上，C-C 键的裂解是通过协同的碳位和碳烯机制发生的，而在固体酸的情况下则是通过碳位发生的。在 MWW 纳米片 Pill_Ir-ZN_150 样品上支持的亚纳米化 Ir 中，酸性和金属位点特性的最佳组合有助于最终催化剂的高活性。我们希望这些铱催化体系能为环烷烃的氢解转化为高价值产品提供更多机会。

引用次数: 0

Imparting functionality into porphyrin metal–organic framework aerogels with uniform distributions for diversified applications 为均匀分布的卟啉金属有机框架气凝胶注入功能，实现多样化应用

IF 4.8 3区材料科学 Q1 CHEMISTRY, APPLIED

Microporous and Mesoporous Materials

Pub Date : 2024-09-30 DOI: 10.1016/j.micromeso.2024.113355

Yujun Wang , Peng Zhang , Chuantao Hou

The incorporation of various functional nanoentities into pure metal–organic framework (MOF) aerogels can not only introduce additional functionality but also expands the application scenarios of MOF aerogels. Herein, a general and simple strategy for uniform incorporation of various functional nanomaterials into a porphyrin MOF aerogel is presented. Specifically, this strategy primarily involves the introduction of a surfactant polyvinylpyrrolidone (PVP) to disperse the nanomaterials in lipophilic solvents, followed by a direct solvothermal reaction with the precursors of the porphyrin MOF aerogel. Additionally, uniform aerogel composites consisting of two MOF components have also been developed by careful optimizing the reaction conditions. The resulting nanoentity@MOF aerogel composites exhibit positive properties that stem from the synergistic effects between the nanoentities and MOF aerogel, offering advanced applications in areas such as photochemical electrochemistry, adsorption and photodegradation, electrochemical oxygen reduction reaction, and fluorescence.

在纯金属有机框架（MOF）气凝胶中掺入各种功能纳米实体不仅能引入额外的功能，还能拓展 MOF 气凝胶的应用领域。本文介绍了一种将各种功能性纳米材料均匀加入卟啉 MOF 气凝胶的通用而简单的策略。具体来说，该策略主要涉及引入表面活性剂聚乙烯吡咯烷酮（PVP），将纳米材料分散在亲油性溶剂中，然后与卟啉 MOF 气凝胶的前体直接发生溶热反应。此外，通过仔细优化反应条件，还开发出了由两种 MOF 成分组成的均匀气凝胶复合材料。纳米实体@MOF 气凝胶复合材料的良好性能源于纳米实体与 MOF 气凝胶之间的协同效应，可在光化学电化学、吸附与光降解、电化学氧还原反应和荧光等领域提供先进的应用。

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引用次数: 0