Hydrogen absorption in 1 nm Pd clusters confined in MIL-101(Cr)

Fan

et al. 2019

Applied Organom Chemis

Excessive consumption of Fe (II) and massive generation of sludge containing Fe (III) from classic Fenton process remains a major obstacle for its poor recycling of Fe (III) to Fe (II). Therefore, the MHACF‐MIL‐101(Cr) system, by introducing H2, Pd0 and MIL‐101(Cr) into Fenton reaction system, was developed at normal temperature and pressure. In this system, the reduction of FeIII back to FeII by solid catalyst Pd/MIL‐101(Cr) for the storage and activation of H2, was accelerated significantly by above 10‐fold and 5‐fold controlled with the H2‐MIL‐101(Cr) system and H2‐Pd0 system, respectively. However, the concentration of Fe (II) generated by the reduction of Fe (III) could not be detected with the only input of H2 and without the addition of MOFs material. In addition, the apparent consumption of Fe (II) in MHACF‐MIL‐101(Cr) system was half of that in classical Fenton system, while more Fe (II) might be reused infinitely in fact. Accordingly, only trace amount of Fe (II) vs H2O2 concentration was needed and hydroxyl radicals through the detection of para‐hydroxybenzoic acid (p‐HBA) as the oxidative product of benzoic acid (BA) by·OH could be continuously generated for the effective degradation of 4‐chlorophenol(4‐CP). The effects of initial pH, concentration of 4‐CP, dosage of Fe2+, H2O2 and Pd/MIL‐101(Cr) catalyst, Pd content and H2 flow were investigated, combined with systematic controlled experiments. Moreover, the robustness and morphology change of Pd/MIL‐101(Cr) were thoroughly analyzed. This study enables better understanding of the H2‐mediated Fenton reaction enhanced by Pd/MIL‐101(Cr) and thus, will shed new light on how to accelerate Fe (III)/Fe (II) redox cycle and develop more efficient Fenton system.

Section: Introductionmentioning

confidence: 99%

Elimination of 4‐chlorophenol in aqueous solution by the Novel Pd/MIL‐101(Cr)‐Hydrogen‐Accelerated catalytic fenton system

Fan

et al. 2019

Applied Organom Chemis

“…2.6 nm and ca . 1 nm nano‐objects, respectively. These values are determined experimentally and vary almost linearly with the inverse radius, as shown in Figure ‐B, proving that this property depends on the “scaling law”, i. e .…”

Section: Embedding Versus Encapsulationmentioning

confidence: 75%

“…Indeed, a change in the rate limiting step was recently reported for ca . 1 nm Pd nanoparticles embedded into MIL‐101(Cr) from surface recombination or β→α phase transformation for bulk Pd to hydrogen diffusion in Pd clusters …”

Section: Embedding Versus Encapsulationmentioning

confidence: 87%

“… Nanosize effect on the Pd−H phase diagram as schematised in reference (A), reproduced with permission, and the variation of critical temperature (T C ) with the inverse size (1/L) for different sizes of Pd particles: free 4 nm nanoparticles generated by spark discharge, 3 nm polymer‐coated nanoparticles, 2.6 nm polymer‐coated nanoparticles and 1 nm MOF‐embedded clusters (B). The dotted line is a guide for the eyes.…”

Section: Embedding Versus Encapsulationmentioning

confidence: 94%

“…Moreover, the activation energy of desorption of ca . 1 nm Pd embedded into MIL‐101 could be calculated from TDS curves by applying the Kissinger equation …”

Section: Embedding Versus Encapsulationmentioning

confidence: 99%

See 2 more Smart Citations

Interactions of Hydrogen with Pd@MOF Composites

2019

Self Cite

Physisorption and chemisorption of hydrogen on solid-state materials are two fundamentally different interactions, both of which display advantages and drawbacks for hydrogen storage. It has been hypothesised that their combination by merging two classes of materials showing different sorption behaviour towards hydrogen in the same composite may synergistically combine their desirable properties. As representatives of such composites, palladium nanoparticles, nanoclusters, and single atoms have been encapsulated in a metal-organic framework matrix, embedded, or immobilised in its pores, respectively. In this minireview, we review advances on the understanding and potential applications of the combination of Pd with metalorganic framework matrices through the analysis of the nanocomposite materials' interaction with hydrogen and sorption properties.[a] Dr.

Advances and Challenges in Development of Transition Metal Catalysts for Heterogeneous Hydrogenation of Organic Compounds

Ivanytsya,

Subotin,

Gavrilenko

et al. 2023

The Chemical Record

Actual problems of development of catalysts for hydrogenation of heterocyclic compounds by hydrogen are summarized and discussed. The scope of review covers composites of nanoparticles of platinum group metals and 3d metals for heterogeneous catalytic processes. Such problems include increase of catalyst activity, which is important for reduction of precious metals content; development of new catalytic systems which do not contain metals of platinum group or contain cheaper analogues of Pd; control of factors which make influence on the selectivity of the catalysts; achievement of high reproducibility of the catalyst‘s performance and quality control of the catalysts. Own results of the authors are also summarized and described. The catalysts were prepared by decomposition of Pd0 and Ni0 complexes, pyrolysis of Ni2+ and Co2+ complexes deposited on aerosil and reduction of Ni2+ in pores of porous support in situ. The developed catalysts were used for hydrogenation of multigram batches of heterocyclic compounds.