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. 2023 Aug 22;13(1):13707.
doi: 10.1038/s41598-023-40901-3.

Investigation of ortho-positronium annihilation for porous materials with different geometries and topologies

Nguyen Thanh Trung  1 , Nguyen Thuy Duong  2 , Nguyen Quoc Hien  3 , Tran Duy Tap  4 , Nguyen Duc Thanh  5
Affiliations

Investigation of ortho-positronium annihilation for porous materials with different geometries and topologies

Nguyen Thanh Trung et al. Sci Rep. .

Abstract

In this work, we present the results of the ortho-positronium (o-Ps) annihilation lifetimes and nitrogen adsorption measurements for different porous materials and an approach for describing the annihilation of o-Ps in a pore, which results in a surface-volume formula (SVF) for calculating the pore-related o-Ps lifetime. This proposed formula gives the relationship between the o-Ps annihilation rate and the effective pore radius, bulk composition, and pore structure, including pore geometry and topology. The pore-related o-Ps lifetimes of different materials calculated by the SVF are consistent with experimental results for both micro- and mesopores (and macropores) with different geometries and topologies. The SVF is convenient for calculations of pore dimensions for many cases of metal organic frameworks and zeolites. This approach enables us to fully explain the temperature dependence of the o-Ps annihilation lifetime over a wide temperature range, 20-700 K.

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Conflict of interest statement

The authors declare no competing interests.

Figures

Figure 1
Figure 1
The annihilation of o-Ps in a pore (note that the electron density in region III is higher than that of region II).
Figure 2
Figure 2
Comparison of the SVF and other models.
Figure 3
Figure 3
The characteristics of the o-Ps annihilation in the high temperature range (T > 273 K) appear to be different from those in the low temperature range (T < 273 K).
Figure 4
Figure 4
SVF1 simulation is consistent with the data of high-temperature (T ≥ 273 K) of the o-Ps lifetime, whereas SVF2 simulation is consistent with that of low-temperature (T ≤ 273 K).
Figure 5
Figure 5
Comparisons of the o-Ps lifetimes calculated by SVF, RTE, and Dutta et al. with experimental data,.
Figure 6
Figure 6
Comparison of the o-Ps lifetimes calculated by SVF and RTE, and Goworek et al. models with the experimental data.
See this image and copyright information in PMC

References

    1. Amirilargani M, Merlet RB, Hedayati P, Nijmeijer A, Winnubst L, Smet CPM, Sudhölter EJR. MIL-53(Al) and NH2-MIL-53(Al) modified α-alumina membranes for efficient adsorption of dyes from organic solvents. Chem. Commun. 2019;55:4119–4122. - PubMed
    1. Mitchell S, Pinar AB, Kenvin J, Crivelli P, Kärger J, Pėrez-Ramírez J. Structural analysis of hierarchically organized zeolites. Nat. Commun. 2015;6:8633. - PMC - PubMed
    1. Zou D, Liu D, Zhang J. From zeolitic imidazolate framework-8 to metal-organic frameworks (MOFs): Representative substance for the general study of pioneering MOF applications. Energy Environ. Mater. 2018;1:209–220.
    1. Tap TD, Sawada HS, Katsumur Y, Maekawa Y. Poly(ethylene-co-tetrafluoroethylene) (ETFE)-based graft-type polymer electrolyte membranes with different ion exchange capacities: Relative humidity dependence for fuel cell applications. J. Membr. Sci. 2013;447:19.
    1. Babarao R, Sheng Dai S, Jiang D. Effect of pore topology and accessibility on gas adsorption capacity in zeolitic imidazolate frameworks: Bringing molecular simulation close to experiment. J. Phys. Chem. C. 2011;115:8126–8135.