Singlet oxygen produced SrCoO2.5 in environmental protection: extraordinary electronic properties and promoted catalytic performance

• Published in: Journal of sol-gel science and technology 2021-08, Vol.99 (2), p.391-401
• Main Authors: He, Lingfeng, Zhang, Yongli
• Format: Article
• Language: English
• Subjects: Catalysts; Ceramics; Chemistry and Materials Science; Citric acid; Cobalt; Composites; Contaminants; Decontamination; Degradation; Durability; Electron paramagnetic resonance; environment and building applications; Environmental protection; Environmental testing; Glass; Hydroxyl groups; Inorganic Chemistry; Materials Science; Nanotechnology; Natural Materials; Optical and Electronic Materials; Original Paper: Sol-gel and hybrid materials for energy; Reaction mechanisms; Regeneration; Rhodamine; Scavenging; Singlet oxygen; Sol-gel processes; Sustainable development; Synergistic effect; Wastewater treatment
• ISSN: 0928-0707; 1573-4846
• DOI: 10.1007/s10971-021-05574-2

Environmental protection treatment process relies on the robustness, durability, and performance of catalysts to drive the development of cutting-edge sustainable technologies for the elimination of refractory contaminants. Herein, prepared SrCoO 2.5 were successfully prepared through citric acid by sol-gel method, and further utilized as super catalysts to degrade Rhodamine B (RhB) by coupling with peroxymonosulfate (PMS) in environmental protection. Three optimized parameters (SrCoO 2.5 dosage of 0.2 g L −1 , PMS concentration of 0.93 g L −1 , and initial pH of 2) were obtained via Conditional test method in environmental protection. Benefiting from the larger specific surface area, pore-volume, and existence of abundant hydroxyl groups, SrCoO 2.5 prepared through citric acid by sol-gel method with more available active sites exhibited an super efficiency of 99.4% toward catalytic degradation of RhB within 10 min under the optimal conditions. Moreover, SrCoO 2.5 demonstrated durability and long-term stability even during the seven consecutive cycle, it almost regenerates in 500 °C for 1 h. The scavenging experiments and electron paramagnetic resonance technologies revealed that non-radical singlet oxygen ( 1 O 2 ), sulfate radicals(SO 4 • − ) were associated as active species in the SrCoO 2.5 /PMS system. Besides, the reaction mechanism on the SrCoO 2.5 degradation pathways toward RhB was speculated under PMS activation. The results indicated that the synergistic effects between Co–Sr structures not only significantly boosted the removal efficiency and long-term stability of SrCoO 2.5 . But also facilitated the redox cycles of Co 3+ /Co 2+ and Sr 3+ /Sr 2+ , which produce 1 O 2 . This proof-of-concept approach to develop such high-efficient Co–Sr structures produced Co 3+ /Co 2+ and Sr 3+ /Sr 2+ will open up novel avenues for wastewater decontamination via PMS activation. Highlights SrCoO 2.5 materials for environmental protection industry are rarely reported. Such a meaningful applying strategy that involves the SrCoO 2.5 materials for environmental protection industry, as far as we know, has not been reported to activate PMS for remediating RhB in wastewater. Furthermore, the detailed mechanistic study also requires an in-depth discussion. SrCoO 2.5 materials produce 1 O 2 was reported. Synthesis of SrCoO 2.5 with citric acid as the precursor was reported. Regeneration of SrCoO 2.5 materials was reported.