ChemCatChem
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2024
·
IF 3.8
Qi Yang,Ying Zheng,Yi Feng,Jie Ding,Maoshuai Li,Shouying Huang,Mei-Yan Wang,Xinbin Ma
Graphical Synergy between Rh 0 and Rh + on the Rh clusters is essential to catalyze heterogeneous formaldehyde hydroformylation. Rh 0 works as the adsorption/activation site for formaldehyde and hydrogen. Rh + works as the coordination site for CO and PPh 3 . The formed Rh─CH 2 OH* intermediate is responsible for the highly selective hydroformylation to glycolaldehyde. Controlling the metal geometric and electronic structure is of significance in developing efficient catalysts for heterogeneous hydroformylation. This study examines the structural sizes of Rh and Rh + -Rh 0 distribution to construct a highly active catalyst for formaldehyde hydroformylation. The active sites for hydroformylation require several Rh n atoms, while single-atom Rh can solely catalyze hydrogenation. The highest activity was achieved on Rh nanoclusters (0.95 nm), giving a TOF of 191 h −1 and selectivity of 82% for glycolaldehyde formation. The tunability of the electronic properties of Rh nanoclusters and the synergistic interaction between Rh + and Rh 0 are essential for enhanced activity. Pseudo- in situ FT-IR analysis elucidated that formaldehyde adsorbed on Rh nanocluster prefers to produce glycolaldehyde via hydroformylation, while formaldehyde adsorbed on isolated Rh δ+ sites tends to form methanol via hydrogenation. This study provides a new insight into the design of heterogeneous catalysts and guidance for understanding the reaction mechanism for aldehydes/olefins hydroformylation.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Xin-Yi Zhang,Ben-Jian Xin,Zhi-Xiong Huang,Zhen-Yi Gu,Xiao-Tong Wang,Shuo-Hang Zheng,Ming-Yang Ma,Yue Liu,Jun-Ming Cao,Shu-Ying Li,Xing‐Long Wu
The unique electronic and crystal structures of rare earth metals (RE) offer promising opportunities for enhancing the hydrogen evolution reaction (HER) properties of materials. In this work, a series of RE (Sm, Nd, Pr and Ho)-doped Rh@NSPC (NSPC stands for N, S co-doped porous carbon nanosheets) with sizes less than 2 nm are prepared, utilizing a simple, rapid and solvent-free joule-heat pyrolysis method for the first time. The optimized Sm-Rh@NSPC achieves HER performance. The high-catalytic performance and stability of Sm-Rh@NSPC are attributed to the synergistic electronic interactions between Sm and Rh clusters, leading to an increase in the electron cloud density of Rh, which promotes the adsorption of H + , the dissociation of Rh-H bonds and the release of H 2 . Notably, the overpotential of the Sm-Rh@NSPC catalyst is a mere 18.1 mV at current density of 10 mAcm −2 , with a Tafel slope of only 15.2 mV dec -1 . Furthermore, it exhibits stable operation in a 1.0 M KOH electrolyte at 10 mA cm −2 for more than 100 h. This study provides new insights into the synthesis of composite RE hybrid cluster nanocatalysts and their RE-enhanced electrocatalytic performance. It also introduces fresh perspectives for the development of efficient electrocatalysts.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nature Catalysis
·
2024
·Vol. 7
·期 6
·666-677
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IF 42.8
Dou Xiaomeng,Yan Tao,Qian Lixiang,Hou Huaming,Lopez-Haro Miguel,Marini Carlo,Agostini Giovanni,Meira Debora M.,Zhang Xiangjie,Zhang Liang,Cao Zhi,Liu Lichen
Achieving the regioselective hydroformylation of linear α-olefins to linear aldehydes using solid catalysts with regioselectivities comparable to the corresponding homogeneous process is a great challenge in the chemical industry. Despite the tremendous efforts devoted to this research topic, most of the reported heterogeneous metal catalysts still give considerably lower regioselectivities than well-established homogeneous metal catalysts. Here we show the design of efficient Rh-zeolite catalysts, in which subnanometre Rh clusters are selectively confined in the sinusoidal ten-membered-ring channels of MFI zeolite, for the hydroformylation of long-chain linear α-olefins (C 6 –C 12 ) into linear aldehydes with very high linear-to-branched aldehyde ratios (up to 400). The exceptional catalytic performances result from the involvement of the MFI zeolite framework as a rigid solid ligand that accommodates subnanometre Rh clusters in the sinusoidal channels of the MFI zeolite.
研究领域:
化学工程
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催化
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Applied Physics Reviews
·
2023
·Vol. 10
·期 2
·
IF 15
Liu Qingtao,Liu Jieyuan,Liu Xiaofang,Wang Yu,Hong Song,Wu Jianbo,Shang Jiaxiang,Yu Ronghai,Miao Jungang,Shui Jianglan
To develop efficient and durable acidic oxygen–reduction–reaction (ORR) catalysts based on all platinum group metals (PGMs) is crucial for large-scale application of proton-exchange membrane fuel cells (PEMFCs) but challenging. Here, we report a nitrogen coordination-induced strong metal–support interaction that can tune the surface atoms of ORR-inactive PGM clusters into efficient and durable active sites. Taking Rh as an example, the carbonization of Rh-overdoped zeolitic imidazolate framework-8 results in a large number of Rh clusters (with a little atomic Rh) in porous nitrogen-doped carbon. The cluster surface atoms coordinate with the nitrogen of the carbon support, forming much stronger metal–support interactions than that of common N-doped carbon-supported metal nanoparticles. The activity of surface-activated Rh clusters is close to that of Pt/C. The regulation rules for the surface active sites inherit most of the characteristics of the corresponding single-atom catalysts, but without their severe instability problem. This surface activation strategy has also shown applicable to other PGMs, thereby it is a promising way to alleviate the reliance of PEMFCs on platinum.
研究领域:
材料科学
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催化
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能源工程
·
化学
✓ 已验证
产品关联
DOI
高影响因子
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