In Situ Construction of a MgSn(OH)6 Perovskite/SnO2 Type-II Heterojunction: A Highly Efficient Photocatalyst towards Photodegradation of Tetracycline

Abstract

Using solar energy to remove antibiotics from aqueous environments via photocatalysis is highly desirable. In this work, a novel type-II heterojunction photocatalyst, MgSn(OH)6/SnO2, was successfully prepared via a facile one-pot in situ hydrothermal method at 220 °C for 24 h. The obtained heterojunctions were characterized via powder X-ray diffraction, Fourier-transform infrared spectroscopy, transmission electron microscopy, and ultraviolet-visible diffuse reflectance spectroscopy. The photocatalytic performance was evaluated for photodegradation of tetracycline solution under ultraviolet irradiation. The initial concentration of tetracycline solution was set to be 20 mg/L. The prepared heterojunctions exhibited superior photocatalytic activity compared with the parent MgSn(OH)6 and SnO2 compounds. Among them, the obtained MgSn(OH)6/SnO2 heterojunction with MgCl2·6H2O:SnCl4·5H2O = 4:5.2 (mmol) displayed the highest photocatalytic performance and the photodegradation efficiency conversion of 91% could be reached after 60 min under ultraviolet irradiation. The prepared heterojunction maintained its performance after four successive cycles of use. Active species trapping experiments demonstrated that holes were the dominant active species. Hydroxyl radicals and superoxide ions had minor effects on the photocatalytic oxidation of tetracycline. Photoelectrochemical measurements were used to investigate the photocatalytic mechanism. The enhancement of photocatalytic activity could be assigned to the formation of a type-II junction photocatalytic system, which was beneficial for efficient transfer and separation of photogenerated electrons and holes. This research provides an in situ growth strategy for the design of highly efficient photocatalysts for environmental restoration.

Photo-driven Interfacial Electron Transfer Reduction of cis-[Co(phen) 2 Cl 2 ]Cl Complex by Heterojunctioned CeO 2 /SnO 2 Nanocomposite with Insight on the Role of Supercapacitance

“…7a). The CeO 2 /SnO 2 nanocomposite exhibits good elasticity and stability, 1Ag − 1 by the uniform shape of the CV curve calculates maximum speci c capacitance values for the CeO 2 /SnO 2 nanocomposite of 718 Fg − 1 [27,59].…”

“…The synergistic effects of CeO 2 and graphene are primarily responsible for this remarkable electrochemical performance. CeO 2 /rGO nanocomposites have good electrochemical characteristics for energy storage applications, implying that they might be used as supercapacitors [25][26][27].…”

Sn1/3Na2/3Sn(OH)6 Perovskite with Sn4+/Na+ Disorder for Photocatalytic Degradation of 2,4-Dichlorophenol

“…For instance, cubic MSn­(OH) 6 (M = Mg and Ca) were utilized to photodegrade dyes. , Nanotubular CoSn­(OH) 6 is considered to be an efficient photocatalyst for CO 2 reduction, and ZnSn­(OH) 6 can photodegrade benzene . However, while these parent photocatalysts have been extensively researched, lattice disorder remains relatively under-researched as a means to optimize their photocatalytic properties.…”

Highly Selective Voltammetric Sensor for l-Tryptophan Using Composite-Modified Electrode Composed of CuSn(OH)6 Microsphere Decorated on Reduced Graphene Oxide

“…14,15 The superior electrocatalytic activity observed for CSOH is because the metal ions are octahedrally coordinated with OH to form Cu(OH) 6 and Sn(OH) 6 polyhedra that connect with each other by sharing O atoms to build the whole crystalline structure. 16 Because they have different Shannon radii, this type of hydroxides showing multiple crystalline symmetries are widely used as electrode catalysts for sustainable applications. Nevertheless, only few reports on the applications of perovskite-type hydroxide for the electrochemical detection of biomolecule are available.…”

“…Copper hexahydroxystannate (CuSn­(OH) 6 ), with a structure of ReO 3 derivative, − has been widely applied in photocatalysis, supercapacitors, and batteries . Compared to the different synthesized methods, the co-precipitation method is convenient and straightforward to synthesize CuSn­(OH) 6 (CSOH will be used hereafter) microspheres/microcubes and nanocubes. , The superior electrocatalytic activity observed for CSOH is because the metal ions are octahedrally coordinated with OH to form Cu­(OH) 6 and Sn­(OH) 6 polyhedra that connect with each other by sharing O atoms to build the whole crystalline structure . Because they have different Shannon radii, this type of hydroxides showing multiple crystalline symmetries are widely used as electrode catalysts for sustainable applications.…”