The roles of density and oxygen concentration on the structure of silica aerogel: Insight from an atomistic study
Source abstract
Abstract
Abstract The structure of silica aerogels has strong dependence on the density ρ and oxygen concentration. In this study, molecular dynamic simulations are performed to study the roles of ρ and O/Si molar ratio (OSMR) on the structure of silica aerogels. The average pore size and porosity of silica aerogels increase with decreasing ρ. The OSMR influences the structure by changing the forming ability of tenuous ligaments in silica aerogels. The forming ability of tenuous ligaments decreases with decreasing OSMR from 2.0 to 1.9; then increases with further decreasing OSMR to 1.5. The increasing tenuous ligaments in silica aerogel leads to the dispersed ligaments and small average pore size. This study explains the correlation between the ρ, OSMR and the structure of silica aerogel, which can further guide to tune the structure of silica aerogels in experiments.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Aerogels and thermal insulation · Mesoporous Materials and Catalysis · Surface Modification and Superhydrophobicity
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (47)
Show source-provided references
1. Aerogels and related porous materials10.1021/cr00094a003 ↗
2. Coherent expanded aerogels and jellies10.1038/127741a0 ↗
3. Aerogel applications10.1016/S0022-3093(98)00135-5 ↗
4. Colloidal aggregation phenomena: spatial structuring of TEOS-derived silica aerogels10.1016/j.jcis.2005.11.064 ↗
5. Flexible and transparent silica aerogels: an overview10.4191/kcers.2017.54.3.12 ↗
6. Koebel · 2011
7. Silica aerogel: synthesis and applications10.1155/2010/409310 ↗
8. Mechanical properties and brittle behavior of silica aerogels10.3390/gels1020256 ↗
9. Organic inorganic hybrid aerogels with high mechanical properties via organotrialkoxysilane-derived sol-gel process10.2109/jcersj2.119.16 ↗
10. Nanoengineering strong silica aerogels10.1021/nl025690e ↗
11. Physical properties of methyltrimethoxysilane based elastic silica aerogels prepared by the two-stage sol–gel process10.1007/s10853-006-1409-5 ↗
12. Monolithic silsesquioxane materials with well-defined pore structure10.1557/jmr.2014.332 ↗
13. Chemical, physical, and mechanical characterization of isocyanate cross-linked amine-modified silica aerogels10.1021/cm0513841 ↗
14. Advances in precursor system for silica-based aerogel production toward improved mechanical properties, customized morphology, and multifunctionality: a review10.1016/j.cis.2020.102101 ↗
15. Manipulation of pore size distributions in silica and ormosil gels dried under ambient pressure conditions10.1016/S0022-3093(01)01051-1 ↗
16. Low thermal-conductivity and high thermal stable silica aerogel based on MTMS/Water-glass co-precursor prepared by freeze drying10.1016/j.matdes.2016.09.083 ↗
17. Preparation of compressible silica aerogel reinforced by bacterial cellulose using tetraethylorthosilicate and methyltrimethoxylsilane co-precursor10.1016/j.jnoncrysol.2017.12.015 ↗
18. Force fields for silicas and aluminophosphates based on ab initio calculations10.1103/PhysRevLett.64.1955 ↗
19. Amorphous silica modeled with truncated and screened coulomb interactions: a molecular dynamics simulation study10.1063/1.2777136 ↗
20. Interaction potential for SiO2: a molecular-dynamics study of structural correlations10.1103/PhysRevB.41.12197 ↗
21. Molecular dynamics methods and large-scale simulations of amorphous materials
22. A molecular dynamics study of the thermal conductivity of nanoporous silica aerogel, obtained through negative pressure rupturing10.1016/j.jnoncrysol.2012.03.007 ↗
23. A novel method to predict the thermal conductivity of nanoporous materials from atomistic simulations10.1016/j.jnoncrysol.2019.04.017 ↗
24. Elasticity and strength of silica aerogels: a molecular dynamics study on large volumes10.1016/j.actamat.2017.12.005 ↗
25. Nanocompression of secondary particles of silica aerogel10.1016/j.scriptamat.2018.07.039 ↗
26. Structure and mechanical properties of silica aerogels and xerogels modeled by molecular dynamics simulation10.1016/j.jnoncrysol.2010.03.019 ↗
27. Mechanics of nanostructured porous silica aerogel resulting from molecular dynamics simulations10.1021/acs.jpcb.7b03184 ↗
28. Fracture of silica aerogels: an all-atom simulation study10.1016/j.jnoncrysol.2018.06.005 ↗
29. Molecular dynamics investigation of the shock response of silica aerogels
30. Molecular dynamics and experimental studies of nanoindentation on nanoporous silica aerogels10.1016/j.msea.2018.11.019 ↗
31. Nanoindentation of graphene-reinforced silica aerogel: a molecular dynamics study10.3390/molecules24071336 ↗
32. Mechanical properties and behavior of glass fiber-reinforced silica aerogel nanocomposites: insights from all-atom simulations10.1016/j.scriptamat.2019.10.010 ↗
33. Molecular dynamics simulations of silica aerogel nanocomposites reinforced by glass fibers, graphene sheets and carbon nanotubes: a comparison study on mechanical properties10.1016/j.compositesb.2020.107884 ↗
34. Fast parallel algorithms for short-range molecular dynamics10.1006/jcph.1995.1039 ↗
35. Force fields for silicas and aluminophosphates based on ab initio calculations10.1103/PhysRevLett.64.1955 ↗
36. Generation of fractal structures by negative pressure rupturing of SiO2 glass10.1016/0022-3093(88)90286-4 ↗
37. Fast method for computing pore size distributions of model materials10.1021/la052651k ↗
38. Iler · 1979
39. Visualization and analysis of atomistic simulation data with OVITO–the open visualization tool10.1088/0965-0393/18/1/015012 ↗
40. Structural correlations in porous silica: molecular dynamics simulation on a parallel computer10.1103/PhysRevLett.71.85 ↗
41. Different kinds of fractal structures in silica aerogels10.1016/0022-3093(90)90131-5 ↗
42. Advanced three dimensional characterization of silica-based ultraporous materials10.1039/C5RA26014K ↗
43. The monolithic silica aerogel derived from MTMS/TEOS10.4028/www.scientific.net/AMM.364.631 ↗
44. Symmetrical tilt grain boundary engineering of NiTi shape memory alloy: an atomistic insight10.1016/j.matdes.2017.10.032 ↗
45. The role of strain glass state in the shape memory alloy Ni50+xTi50−x: Insight from an atomistic study10.1016/j.matdes.2017.02.011 ↗
46. Modified aging process for silica aerogel10.1016/j.jmatprotec.2008.04.009 ↗
47. Synthesis of silica aerogel particles and its application to thermal insulation paint10.1007/s11814-020-0574-6 ↗