Impact of the polydispersion of TiO2 materials on their particle size calculated from specific surface area results obtained during an interlaboratory comparison exercise--颗粒学报PARTICUOLOGY

Impact of the polydispersion of TiO₂ materials on their particle size calculated from specific surface area results obtained during an interlaboratory comparison exercise

Sébastien Bau a, Sébastien Artous b, Sébastien Jacquinot b, Dominique Locatelli b, Jean-François Hochepied c e, Nicolas Feltin d, Carine Chivas-Joly d

a INRS, Pollutant Metrology Division, 1 Rue du Morvan, 54500, Vandoeuvre les Nancy, France
b Univ. Grenoble Alpes, CEA, Liten, DTNM, 38000, Grenoble, France
c Unité de Chimie et Procédés (UCP), ENSTA Paris, Institut Polytechnique de Paris, 91120, Palaiseau, France
d LNE, CARMEN Plateform - Nanometrology, 29 Avenue Roger Hennequin, 78197, Trappes Cedex, France
e Centre des Matériaux, Mines Paris, Université PSL, 91003, Evry, France

10.1016/j.partic.2025.01.002

Volume 98, March 2025, Pages 31-40

Received 16 July 2024, Revised 9 January 2025, Accepted 10 January 2025, Available online 17 January 2025, Version of Record 7 February 2025.

E-mail: Carine.chivas-joly@lne.fr

Highlights

• Four TiO₂ with different crystal structures, particle shapes and surface coatings investigated.

• Inter-laboratory comparison of specific surface-area, density and size distribution.

• Constituent particle diameter determined from volume specific surface area (VSSA) accounting for polydispersion.

• Particle diameters obtained from VSSA and EM measurements within ±20%.

Abstract

In this work, four samples of TiO₂ powder materials with different structures (rutile, anatase), surface coatings and morphologies (rod, pseudo-spherical) were characterized by four partners involving complementary methods. With the aim of producing inter-laboratory reproducibility data, the specific surface-area, bulk density, and number size distribution were measured, yielding a satisfying agreement between partners. The equivalent diameter of constituent particles was determined from the sample volume specific surface area (VSSA) – accounting for polydispersion – and compared to electron microscopy (EM). Constituent particle diameters ranged from 15 to 225 nm according to EM analyses. The relative discrepancies between VSSA-based and EM-based diameters were found within ±20%. Out of the four samples under study, TiO₂ μ-rutile leads to a larger deviation, which was attributed to surface coating thanks to complementary analysis. Assuming that the sample is pure, an equivalent diameter based on the VSSA can be determined, provided that the shape of constituent particles is known or supposed.

Graphical abstract

Keywords

Size measurement; TiO₂; BET; Nanoparticle; Volume specific surface area

文章导读