{"title":"Direct Z-scheme heterojunctions with perylenetetracarboxylic diimide decorated amino-rich porous g-C3N4 nanosheets for metal-free photocatalytic N2 fixation","authors":"Donghui Cui, Xue Yang, Yu Liu, Meixi Li, Chunxue Wang, Fengyan Li","doi":"10.1016/j.seppur.2024.130035","DOIUrl":null,"url":null,"abstract":"Photocatalytic nitrogen fixation is a green, sustainable ammonia synthesis method in artificial nitrogen fixation technology. However, activating inert nitrogen molecules requires a great deal of energy, and the design of stable and efficient nitrogen-fixing photocatalysts is of great research value and challenge. In this paper, g-C<sub>3</sub>N<sub>4</sub> nanosheets (10H-CN<sub>v</sub>) containing nitrogen-vacancy curled porous ammonia-rich structure and perylenetetracarboxylic diimide (PDI) are covalently combined bonded by the in-situ condensation to construct direct Z-scheme heterojunction photocatalysts. Among them, the nitrogen vacancies and the curled porous morphology endow 10H-CN<sub>v</sub> with more active sites for N<sub>2</sub> adsorption. The direct Z-scheme heterojunction is constructed with an enhanced internal built-in electric field, effectively promoting the selective accumulation of photogenerated electrons and holes in the 10H-CN<sub>v</sub> and PDI components. Sufficient redox potentials provide a potential driving force for lowering the activation energy barrier of inert nitrogen molecules. In addition, the direct Z-scheme heterojunction in charge transfer mode enables efficient spatial separation of photogenerated electrons and holes. The average yields of 30 % PDI/10H-CN<sub>v</sub> photocatalyzed direct conversion of N<sub>2</sub> molecules to ammonia and nitrate are 519.2 and 135.9 μmol g<sup>−1</sup>h<sup>−1</sup>, respectively. This work gives valuable guidelines for directly constructing Z-scheme heterostructures of photocatalysts for their application in nitrogen fixation.","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":null,"pages":null},"PeriodicalIF":8.1000,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Separation and Purification Technology","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.1016/j.seppur.2024.130035","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: 0
Abstract
Photocatalytic nitrogen fixation is a green, sustainable ammonia synthesis method in artificial nitrogen fixation technology. However, activating inert nitrogen molecules requires a great deal of energy, and the design of stable and efficient nitrogen-fixing photocatalysts is of great research value and challenge. In this paper, g-C3N4 nanosheets (10H-CNv) containing nitrogen-vacancy curled porous ammonia-rich structure and perylenetetracarboxylic diimide (PDI) are covalently combined bonded by the in-situ condensation to construct direct Z-scheme heterojunction photocatalysts. Among them, the nitrogen vacancies and the curled porous morphology endow 10H-CNv with more active sites for N2 adsorption. The direct Z-scheme heterojunction is constructed with an enhanced internal built-in electric field, effectively promoting the selective accumulation of photogenerated electrons and holes in the 10H-CNv and PDI components. Sufficient redox potentials provide a potential driving force for lowering the activation energy barrier of inert nitrogen molecules. In addition, the direct Z-scheme heterojunction in charge transfer mode enables efficient spatial separation of photogenerated electrons and holes. The average yields of 30 % PDI/10H-CNv photocatalyzed direct conversion of N2 molecules to ammonia and nitrate are 519.2 and 135.9 μmol g−1h−1, respectively. This work gives valuable guidelines for directly constructing Z-scheme heterostructures of photocatalysts for their application in nitrogen fixation.
期刊介绍:
Separation and Purification Technology is a premier journal committed to sharing innovative methods for separation and purification in chemical and environmental engineering, encompassing both homogeneous solutions and heterogeneous mixtures. Our scope includes the separation and/or purification of liquids, vapors, and gases, as well as carbon capture and separation techniques. However, it's important to note that methods solely intended for analytical purposes are not within the scope of the journal. Additionally, disciplines such as soil science, polymer science, and metallurgy fall outside the purview of Separation and Purification Technology. Join us in advancing the field of separation and purification methods for sustainable solutions in chemical and environmental engineering.