1
|
Adsorption and Mechanism of Glycine on the Anatase with Exposed (001) and (101) Facets. MINERALS 2022. [DOI: 10.3390/min12070798] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
As a widely existing mineral types on Earth, semiconductor minerals play an important role in the origin of life and the material geochemical cycle. The first step of peptide formation is amino acid adsorption on the mineral surface, but the role and mechanism of different crystal facets of semiconductor minerals are not well understood. Anatase (TiO2) with exposed (001) facets was synthesized by a hydrothermal method, and then analyzed and compared with the purchased ordinary anatase (TiO2) for the adsorption of glycine, the simplest amino acid. XRD, SEM and TEM results show that the hydrothermally synthesized anatase (TiO2) has a good anatase crystal form, which is micro-nano-scale flake particles and mainly composed of (001) facets. The results of HPLC used in the adsorption experiment showed that under optimal conditions (pH 5 to 6, an adsorption time of 24 h, and an initial concentration of 0.09 mol/L), the adsorption quantity of glycine on anatase (TiO2) with exposed (001) facets may reach 10 mg/m2, which is larger than that for ordinary anatase (TiO2) with exposed (101) facets. Based on a combination of various characterizations and simulation calculations, the results proved that anatase can activate thermodynamically stable γ-glycine to β-glycine. The adsorption of glycine on anatase (TiO2) has two forms, one is the zwitterionic form in which the carboxyl group forms a bridge structure with two Ti atoms connected by surface bridging oxygen, and the dissociated form is in which the amino group forms a bond with the surface Ti atom. Among these, glycine is mainly adsorbed to anatase by dissociative molecules on the anatase (TiO2) with exposed (001) facets and by zwitterion adsorption on the anatase (TiO2) with exposed (101) facets. This research elucidates the conditions and mechanism of amino acid adsorption by semiconductor minerals in weak acidic environment, which is similar to the environmental pH that was beneficial to the formation of life on the early Earth. Therefore, these can provide a reference for the further study of the role of semiconductor minerals in the adsorption and polymerization of small biomolecules in the origin of life.
Collapse
|
2
|
Du Y, Niu X, Zhang C, Li X, Cai X, Guo Y, Wang P. FacileSynthesis of Anatase TiO
2
Nanocrystals with Co‐Exposed{101}, {010}/{100} and [111]‐Facets for EfficientPhotodegradation of Methylene Blue. ChemistrySelect 2021. [DOI: 10.1002/slct.202004195] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Yi‐en Du
- School of Chemistry & Chemical Engineering Jinzhong University Jinzhong 030619 China
| | - Xianjun Niu
- School of Chemistry & Chemical Engineering Jinzhong University Jinzhong 030619 China
| | - Caifeng Zhang
- Department of Chemistry Taiyuan Normal University Jinzhong 030619 China
| | - Xiaodong Li
- School of Chemistry & Chemical Engineering Jinzhong University Jinzhong 030619 China
| | - Xuemei Cai
- School of Chemistry & Chemical Engineering Jinzhong University Jinzhong 030619 China
| | - Yanqing Guo
- School of Chemistry & Chemical Engineering Jinzhong University Jinzhong 030619 China
| | - Pengfei Wang
- State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 China
| |
Collapse
|