Impact Factor:

13.1

DOI number:

10.1021/acs.est.5c05288

Journal:

Environmental Science & Technology

Abstract:

Hematite’s common (001) and (012) facets are frequently used in model studies of lead (Pb) adsorption behavior, but there is a lack of research on the high-energy facets, e.g., (104), present in nature. Also, few studies have attempted to connect the molecular details of facet-specific Pb adsorption to the macroscopic uptake behavior. To address these knowledge gaps, we investigated Pb(II) adsorption behaviors on facet-engineered hematite nanoparticles dominated by (001), (104), and (116). Adsorption experiments revealed significant variations in Pb(II) uptake among the three samples, with (001) demonstrating the highest capacity and (116) showing the best adsorption efficiency when normalized to the specific surface area. Adsorption kinetics followed the pseudo-second-order model, indicating that the adsorption process is governed mostly by chemisorption. Adsorption isotherms were well fitted by the Langmuir model, indicating that uptake proceeds until roughly monolayer adsorption. Detailed characterization revealed Pb(II) was adsorbed as single atoms with complex inner-sphere binding modes that varied across different facets, indicating that adsorption is both structurally and energetically facet-dependent. Coadsorption experiments further demonstrated Cu2+, Zn2+, and humic acid significantly promoted Pb(II) adsorption. This study advances the understanding of hematite surface reactivity in controlling macroscopic wet adsorption behaviors, providing valuable insights into the environmental fate of Pb(II).

Co-author:

Micah P Prange, Duo Song, Sungsik Lee, Sang Soo Lee, Juejing Liu, Yatong Zhao, Xiang Wang, Mark H Engelhard, Yadong Zhou, Yifu Feng, Nikita Basilyan, Xiaoxu Li, Carolyn I Pearce, Zheming Wang, Zihua Zhu

First Author:

Ping Chen

Indexed by:

Journal paper

Correspondence Author:

Kevin M Rosso, Xin Zhang

Discipline:

Engineering

Document Type:

J

Volume:

59

Issue:

23

Page Number:

11862–11874

Translation or Not:

no

Date of Publication:

2025-06-02

Included Journals:

SCI

Links to published journals:

https://pubs.acs.org/doi/abs/10.1021/acs.est.5c05288