A critical review of covalent triazine framework-based materials: Bibliometric study, synthesis, enhancement strategies, emerging applications, and DFT insights

Covalent triazine frameworks (CTFs), an intriguing member of the porous organic polymers (POPs), have garnered global attention in various applications due to their remarkable properties. This review adopted a bibliometric analysis to evaluate the trends of CTFs research since its first synthesis in 2008. The Scopus database was utilised to obtain data on CTFs from 2008 to 2024, and VOSviewer version 1.6.16 data visualisation software was employed to analyse co-authorship among countries and the co-occurrence of keywords. Among the 949 documents written in the English language that have been published on CTFs from 2008 to 2024, 870 (91.68%) were research articles, 61 (6.43%) belonged to review papers, and the remaining 18 (1.90%) were book chapters, conference proceedings, and others. China, with 646 documents and 26,348 citations, was the leading country in co-authorship occurrences, followed by Germany with 105 papers and 11,071 citations. Carbon dioxide, adsorption, and photocatalysis, with 169, 129, and 125 occurrences, respectively, were the most frequently used keywords, suggesting the research hotspots of CTFs application from 2008 to 2024. This review further classifies the synthesis of CTFs into five categories (ionothermal, acid-catalysed synthesis, carbon coupling, base-catalysed synthesis, and microwave synthesis). The various enhancement strategies were discussed, as well as their environmental (photocatalysis, Fenton-like catalysis, and photothermal) and biomedical (drug/gene delivery and disinfection) applications. Furthermore, its application, based on density functional theory (DFT) calculations, is highlighted. Overall, this review outlines the roadmap of CTFs in various applications since their discovery, serving as a guide for future research.