MOF-templated hollow cobalt sulfide as an enhanced Oxone activator for degradation of UV Absorber: Key role of sulfur Vacancy-Induced highly active CoII sites
Ta Cong Khiem , Xiaoguang Duan , Wei-Jie Liu , Young-Kwon Park , Ha Manh Bui , Wen-Da Oh , Suresh Ghotekar , Yiu Fai Tsang , Kun-Yi Andrew Lin
{"title":"MOF-templated hollow cobalt sulfide as an enhanced Oxone activator for degradation of UV Absorber: Key role of sulfur Vacancy-Induced highly active CoII sites","authors":"Ta Cong Khiem , Xiaoguang Duan , Wei-Jie Liu , Young-Kwon Park , Ha Manh Bui , Wen-Da Oh , Suresh Ghotekar , Yiu Fai Tsang , Kun-Yi Andrew Lin","doi":"10.1016/j.cej.2022.139699","DOIUrl":null,"url":null,"abstract":"<div><p>This study aimed to design hollow rhombic cobalt sulfide (HRCS) via a single-step sulfidation of cobaltic metal organic framework (CoMOF) as a template. The obtained HRCS with abundance of defects and sulfur vacancy (SV) was then employed for degradation of Novantisol (NVT), a sunscreen agent, through Oxone activation. The superior catalytic performance of HRCS was attributed to its more electroactive sites and low charge transfer resistance that were enhanced by highly active Co<sup>II</sup> due to the existence of SV for increased generation of SO<sub>4</sub><sup>•−</sup> as a predominant species. Although <sup>•</sup>OH and <sup>1</sup>O<sub>2</sub> were proved to be generated obviously from activation of Oxone over HRCS, their contribution to NVT degradation was marginal. While <sup>•</sup>OH and SO<sub>4</sub><sup>•−</sup> were generated mainly by Co<sup>II</sup>-activated Oxone, the formation of SO<sub>4</sub><sup>•−</sup> was accelerated by sulfur species and the disproportionation of SO<sub>5</sub><sup>•−</sup>. The limited conversion of SO<sub>4</sub><sup>•−</sup> by reacting with <sup>−</sup>OH and undirect self-hydrolysis of Oxone, on the other hand, contributed to enhanced <sup>•</sup>OH generation. Further experiments on furfuryl alcohol (FFA) consumption showed that <sup>1</sup>O<sub>2</sub> generated from O<sub>2</sub><sup>•−</sup> as an intermediate species did not account for the NVT degradation but rather from self-decomposition of Oxone, dissociation and self-combination of SO<sub>5</sub><sup>•−</sup>, and disproportionation of <sup>•</sup>OH. The degradation pathway was also investigated and unveiled in details via DFT calculation, which further validated that HRCS appeared to be a superior catalyst for NVT degradation through Oxone activation.</p></div>","PeriodicalId":270,"journal":{"name":"Chemical Engineering Journal","volume":null,"pages":null},"PeriodicalIF":13.3000,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"15","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Chemical Engineering Journal","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1385894722051786","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, CHEMICAL","Score":null,"Total":0}
引用次数: 15
Abstract
This study aimed to design hollow rhombic cobalt sulfide (HRCS) via a single-step sulfidation of cobaltic metal organic framework (CoMOF) as a template. The obtained HRCS with abundance of defects and sulfur vacancy (SV) was then employed for degradation of Novantisol (NVT), a sunscreen agent, through Oxone activation. The superior catalytic performance of HRCS was attributed to its more electroactive sites and low charge transfer resistance that were enhanced by highly active CoII due to the existence of SV for increased generation of SO4•− as a predominant species. Although •OH and 1O2 were proved to be generated obviously from activation of Oxone over HRCS, their contribution to NVT degradation was marginal. While •OH and SO4•− were generated mainly by CoII-activated Oxone, the formation of SO4•− was accelerated by sulfur species and the disproportionation of SO5•−. The limited conversion of SO4•− by reacting with −OH and undirect self-hydrolysis of Oxone, on the other hand, contributed to enhanced •OH generation. Further experiments on furfuryl alcohol (FFA) consumption showed that 1O2 generated from O2•− as an intermediate species did not account for the NVT degradation but rather from self-decomposition of Oxone, dissociation and self-combination of SO5•−, and disproportionation of •OH. The degradation pathway was also investigated and unveiled in details via DFT calculation, which further validated that HRCS appeared to be a superior catalyst for NVT degradation through Oxone activation.
期刊介绍:
The Chemical Engineering Journal is an international research journal that invites contributions of original and novel fundamental research. It aims to provide an international platform for presenting original fundamental research, interpretative reviews, and discussions on new developments in chemical engineering. The journal welcomes papers that describe novel theory and its practical application, as well as those that demonstrate the transfer of techniques from other disciplines. It also welcomes reports on carefully conducted experimental work that is soundly interpreted. The main focus of the journal is on original and rigorous research results that have broad significance. The Catalysis section within the Chemical Engineering Journal focuses specifically on Experimental and Theoretical studies in the fields of heterogeneous catalysis, molecular catalysis, and biocatalysis. These studies have industrial impact on various sectors such as chemicals, energy, materials, foods, healthcare, and environmental protection.