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Defects are common features in hematite that arise from deviations from the perfect mineral crystal structure. Vacancy defects have been shown to significantly enhance arsenate (As) immobilization by hematite. However, the contributions from vacancy defects on different exposed facets of hematite have not been fully quantified. In this study, hematite samples with various morphologies were pretreated with sodium borohydride (NaBH) to generate oxygen vacancy defects (OVDs), analyzed quantitatively using extended X-ray absorption fine structure (EXAFS) and thermogravimetric analysis (TG). Batch experiments revealed that the OVDs on different exposed facets showed significant variations in improving arsenate adsorption, i.e., the quantitative enhancement of arsenate adsorption amount per unit OVD concentration (Δ/) followed the sequence of (110) facet (80.05 μmol/mmol) > (001) facet (31.85 μmol/mmol) > (012) facet (13.14 μmol/mmol). The underlying mechanism by which OVDs affect arsenate adsorption across different exposed facets of hematite was studied. The results reveal that the tremendous improvement of arsenate adsorption caused by OVDs on the (110) facet compared to (001) and (012) facets was attributed to their stronger bonding strength of As to under-coordinated Fe atoms, thus significantly promoting the immobilization of arsenate. The findings of this study enhance our ability to precisely understand the migration and fate of As while also aiding in the design of highly efficient iron mineral materials for mitigating As pollution.
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http://dx.doi.org/10.1021/acs.est.4c11344 | DOI Listing |
Adv Mater
September 2025
Key Lab of Artificial Micro- and Nano-Structures of Ministry of Education of China, School of Physics and Technology, Wuhan University, Wuhan, 430072, China.
Sequential deposition technique is widely used to fabricate perovskite films with large grain size in perovskite solar cells (PSCs). Residual lead halide (PbI) in the perovskite film tends to be decomposed into metallic lead (Pb) under long-term heating or light soaking. Here, a chiral levetiracetam (LEV) dopant containing α-amide and pyrrolidone groups is introduced into the PbI precursor solution.
View Article and Find Full Text PDFDalton Trans
September 2025
School of Electronics and Information Engineering, Hebei University of Technology, Tianjin Key Laboratory of Electronic Materials and Devices, 5340 Xiping Road, Beichen District, Tianjin, 300401, China.
Layered double hydroxides (LDHs) have attracted considerable attention in gas sensing applications due to their highly tunable chemical composition and unique two-dimensional layered architecture. In this study, a series of ZnAl-LDHs with varying Zn/Al molar ratios were synthesized a facile hydrothermal method, and their ethanol sensing performance at room temperature was systematically evaluated. The influence of composition on the structural, morphological, and electronic properties of the materials was thoroughly investigated using a suite of characterization techniques, including XRD, FTIR, SEM, TEM, BET, XPS, PL, and EPR.
View Article and Find Full Text PDFWater Res
August 2025
State Key Laboratory of Environmental Aquatic Chemistry, Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
Phosphorus is recognized as a major pollutant in municipal and domestic wastewater, but the effective removal of organic phosphorus (OP) using conventional wastewater treatment technologies is difficult. Herein, a novel visible light-enhanced Ti electrocoagulation (EC) technology was proposed for the removal of OP using 2-amino-ethyl phosphonic acid (AEP) as a model compound to elucidate the removal efficiency and mechanisms. The results showed that the irradiation under visible light (670 Lux) effectively enhanced the removal of AEP by Ti EC.
View Article and Find Full Text PDFNano Lett
September 2025
School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China.
Multijunction photoelectrodes, which generate active photocarriers with sufficient energy to drive unassisted solar-fuel conversion, represent a promising avenue for sustainable energy applications. However, achieving controllable p/n-type doping and high-quality growth remains a challenge for most emerging metal oxide semiconductors. In this study, we demonstrate the creation of in-plane ferroelectric p/n homojunction superstructures in BiFeO (BFO) films, enabling bias-free photoelectrochemical (PEC) reactions.
View Article and Find Full Text PDFACS Appl Mater Interfaces
September 2025
Key Laboratory of Atomic and Molecular Physics & Functional Materials of Gansu Province, College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070, China.
Overcoming the persistent challenges of high operating temperatures and poor selectivity in metal oxide semiconductor (MOS) gas sensors, this work enhances defect sites in the sensing material through heterostructure construction and builds mesoporous architectures using MOF-derived carbon skeletons as templates. The synergistic effects of multiple mechanisms significantly improve gas-sensing performance, successfully fabricating a ZnO/PCS flexible room-temperature gas sensor with exceptional room-temperature DMF detection capabilities. The nitrogen-containing porous carbon skeletons (PCSs) template shows a stable mesoporous microstructure with large pore volume.
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