Solid-Phase Synthesis of Non-metal (S, N)-Doped Tin Oxide Nanopowders at Room Temperature and its Photodegradation Properties for Wastewater of Biomass Treatment

• Published in: Journal of inorganic and organometallic polymers and materials 2022-07, Vol.32 (7), p.2748-2762
• Main Authors: Liu, Shao-You, Wang, Qian, Ou, Li-Hui, Du, Hong-Li, Long, You, Zhen, Wei-Jun
• Format: Article
• Language: English
• Subjects: Ammonia; Biomass; Chemistry; Chemistry and Materials Science; Dehydration; Energy bands; Energy gap; Hydroxyl radicals; Inorganic Chemistry; Metal hydroxides; Nitrogen; Organic Chemistry; Performance degradation; Photodegradation; Polymer Sciences; Room temperature; Solid phase synthesis; Tin; Tin dioxide; Tin oxides; Toluene; Ultraviolet radiation; Wastewater treatment
• ISSN: 1574-1443; 1574-1451
• DOI: 10.1007/s10904-022-02296-y

Tin oxide and sulfur, nitrogen-doped tin oxide nano-powder catalysts were prepared by a solid phase reaction at room temperature, using the sodium p -toluene sulfonate (STS) surfactant as template. Theoretical calculation of the dehydration reaction energy of tin hydroxide was performed with the framework of DFT and their structures were characterized. And the UV-light degradation performance and mechanism used for the biomass wastewater were discussed, as well as, its COD and NH 3 -N value. The results show that the large gap of the reaction energy between intramolecular dehydration ( E r = 2.81 eV) and intermolecular dehydration ( E r = 5.77 eV) for tin hydroxide causes the presence of amorphous SnO 2 and metastable tin hydroxide at 450 °C. The entry of S and N into the (110) crystal plane of SnO 2 reduces its energy band gap width, exhibiting the photocatalytic degradation rate (98.9%) of S + N-SnO 2 - STS sample for the rice straw powder treatment wastewater (RSPTW) irradiated by UV-light for 8 h. The excellent degradation capacity of RSPTW mainly comes from the hydroxyl radicals (·OH) and superoxygen radicals (·O 2 − ) produced by the rich hydroxyl on the surface of S + N-SnO 2 - STS due to the regulatory effect of STS and lower calcined temperature. The sewage discharge of photodegraded RSPTW complies with Chinese National Level II Standards.