Insights into antimony adsorption on {001} TiO2: XAFS and DFT study.

Title Insights into antimony adsorption on {001} TiO2: XAFS and DFT study.
Authors L. Yan; J. Song; T.S. Chan; C. Jing
Journal Environ Sci Technol
DOI 10.1021/acs.est.7b00807

Antimony (Sb) contamination poses an emerging environmental risk, whereas its removal remains a contemporary challenge due to the lack of knowledge in its surface chemistry and efficient adsorbent. In this study, self-assembly {001} TiO2 was examined for its effectiveness in Sb removal, and the molecular level surface chemistry was studied with X-ray absorption spectroscopy and density functional theory calculations. The kinetics results show that Sb adsorption followed the pseudo-second order reaction, and the Langmuir adsorption capacity was 200 mg/g for Sb(III) and 156 mg/g for Sb(V). The PZC of TiO2, which was 6.6 prior to the adsorption experiment, shifted to 4.8 and <0 after adsorption of Sb(III) and Sb(V), respectively, indicating the formation of negatively charged inner-sphere complexes. EXAFS results suggest that Sb(III/V) adsorption exhibited a bidentate binuclear surface complex. The orbital hybridizing of complexes was studied by XANES, molecular orbital theory (MO), and density of states (DOS) calculations. The change in orbital energy derived from orbital hybridizing of adsorbed Sb on surfaces is the driving force underlining the Sb surface chemistry. New bonds between Sb and TiO2 surface were formed with matched orbital energies. Integrating the molecular and electronic structures into surface complexation modeling reveals the nature of macroscopic Sb adsorption behaviors.

Citation L. Yan; J. Song; T.S. Chan; C. Jing.Insights into antimony adsorption on {001} TiO2: XAFS and DFT study.. Environ Sci Technol. 2017. doi:10.1021/acs.est.7b00807

Related Elements


See more Antimony products. Antimony (atomic symbol: Sb, atomic number: 51) is a Block P, Group 15, Period 5 element with an atomic radius of 121.760. Antimony Bohr Model The number of electrons in each of antimony's shells is 2, 8, 18, 18, 5 and its electron configuration is [Kr] 4d10 5s2 5p3. The antimony atom has a radius of 140 pm and a Van der Waals radius of 206 pm. Antimony was discovered around 3000 BC and first isolated by Vannoccio Biringuccio in 1540 AD. In its elemental form, antimony has a silvery lustrous gray appearance. Elemental Antimony The most common source of antimony is the sulfide mineral known as stibnite (Sb2S3), although it sometimes occurs natively as well. Antimony has numerous applications, most commonly in flame-retardant materials. It also increases the hardness and strength of lead when combined in an alloy and is frequently employed as a dopant in semiconductor materials. Its name is derived from the Greek words anti and monos, meaning a metal not found by itself.


See more Titanium products. Titanium (atomic symbol: Ti, atomic number: 22) is a Block D, Group 4, Period 4 element with an atomic weight of 47.867. The number of electrons in each of Titanium's shells is [2, 8, 10, 2] and its electron configuration is [Ar] 3d2 4s2. Titanium Bohr ModelThe titanium atom has a radius of 147 pm and a Van der Waals radius of 187 pm. Titanium was discovered by William Gregor in 1791 and first isolated by Jöns Jakob Berzelius in 1825. In its elemental form, titanium has a silvery grey-white metallic appearance. Titanium's properties are chemically and physically similar to zirconium, both of which have the same number of valence electrons and are in the same group in the periodic table. Elemental TitaniumTitanium has five naturally occurring isotopes: 46Ti through 50Ti, with 48Ti being the most abundant (73.8%). Titanium is found in igneous rocks and the sediments derived from them. It is named after the word Titanos, which is Greek for Titans.

Related Forms & Applications