Qinglu Yu , Xing Ming , Yueyang Wang , Long Sun , Mingkai Cui , Guoxing Sun
{"title":"高度分散的LDH纳米片对胶凝材料氯离子结合和防腐的影响","authors":"Qinglu Yu , Xing Ming , Yueyang Wang , Long Sun , Mingkai Cui , Guoxing Sun","doi":"10.1016/j.cemconcomp.2025.106178","DOIUrl":null,"url":null,"abstract":"<div><div>The chemical binding of free chloride ions in cementitious materials, crucial for prolonging their lifespan, relies heavily on aluminate hydrates and can be modulated by incorporating the layered double hydroxides (LDHs). Yet, the currently synthesized LDHs in field of cement and concrete usually suffer from nano crystallites aggregation, limiting their potential as nanofillers and hindering the chloride-capturing efficiency. This study compares the cementitious materials containing highly dispersed LDH nano-platelets (HDLNPs) with those using conventional LDH powder (LP) to unveil the ion-exchange-efficiency-dependent aluminates regulation and particle-size-related pores refinement of LDHs. HDLNPs regulate the sulfate to aluminate balance at a concurrent rate with early-age hydration of tricalcium aluminate (C<sub>3</sub>A) to promote the conversion from ettringite (AFt) to alumino-ferrite-mono (AFm) phases. Furthermore, due to their high dispersion, HDLNPs mitigate the interlayer inertness toward chloride binding induced by carbonation. However, HDLNPs primarily occupy micropores around outer C-S-H, failing to refine capillary pore, which is amplified by the concomitant AFt shortage, leads to higher capillary adsorption rates. Nevertheless, HDLNPs outperform LP in terms of corrosion protection at equivalent dosage, evoking the LDHs’ unsung ion-exchange capacity in delaying chloride ingress. This advancement in the dispersion of incorporated LDHs underscores their valuable roles in designing durable and sustainable cementitious materials.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"163 ","pages":"Article 106178"},"PeriodicalIF":13.1000,"publicationDate":"2025-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Effects of highly dispersed LDH nano-platelets on chloride binding and corrosion protection of cementitious materials\",\"authors\":\"Qinglu Yu , Xing Ming , Yueyang Wang , Long Sun , Mingkai Cui , Guoxing Sun\",\"doi\":\"10.1016/j.cemconcomp.2025.106178\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>The chemical binding of free chloride ions in cementitious materials, crucial for prolonging their lifespan, relies heavily on aluminate hydrates and can be modulated by incorporating the layered double hydroxides (LDHs). Yet, the currently synthesized LDHs in field of cement and concrete usually suffer from nano crystallites aggregation, limiting their potential as nanofillers and hindering the chloride-capturing efficiency. This study compares the cementitious materials containing highly dispersed LDH nano-platelets (HDLNPs) with those using conventional LDH powder (LP) to unveil the ion-exchange-efficiency-dependent aluminates regulation and particle-size-related pores refinement of LDHs. HDLNPs regulate the sulfate to aluminate balance at a concurrent rate with early-age hydration of tricalcium aluminate (C<sub>3</sub>A) to promote the conversion from ettringite (AFt) to alumino-ferrite-mono (AFm) phases. Furthermore, due to their high dispersion, HDLNPs mitigate the interlayer inertness toward chloride binding induced by carbonation. However, HDLNPs primarily occupy micropores around outer C-S-H, failing to refine capillary pore, which is amplified by the concomitant AFt shortage, leads to higher capillary adsorption rates. Nevertheless, HDLNPs outperform LP in terms of corrosion protection at equivalent dosage, evoking the LDHs’ unsung ion-exchange capacity in delaying chloride ingress. This advancement in the dispersion of incorporated LDHs underscores their valuable roles in designing durable and sustainable cementitious materials.</div></div>\",\"PeriodicalId\":9865,\"journal\":{\"name\":\"Cement & concrete composites\",\"volume\":\"163 \",\"pages\":\"Article 106178\"},\"PeriodicalIF\":13.1000,\"publicationDate\":\"2025-06-15\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Cement & concrete composites\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0958946525002604\",\"RegionNum\":1,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"CONSTRUCTION & BUILDING TECHNOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Cement & concrete composites","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0958946525002604","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CONSTRUCTION & BUILDING TECHNOLOGY","Score":null,"Total":0}
Effects of highly dispersed LDH nano-platelets on chloride binding and corrosion protection of cementitious materials
The chemical binding of free chloride ions in cementitious materials, crucial for prolonging their lifespan, relies heavily on aluminate hydrates and can be modulated by incorporating the layered double hydroxides (LDHs). Yet, the currently synthesized LDHs in field of cement and concrete usually suffer from nano crystallites aggregation, limiting their potential as nanofillers and hindering the chloride-capturing efficiency. This study compares the cementitious materials containing highly dispersed LDH nano-platelets (HDLNPs) with those using conventional LDH powder (LP) to unveil the ion-exchange-efficiency-dependent aluminates regulation and particle-size-related pores refinement of LDHs. HDLNPs regulate the sulfate to aluminate balance at a concurrent rate with early-age hydration of tricalcium aluminate (C3A) to promote the conversion from ettringite (AFt) to alumino-ferrite-mono (AFm) phases. Furthermore, due to their high dispersion, HDLNPs mitigate the interlayer inertness toward chloride binding induced by carbonation. However, HDLNPs primarily occupy micropores around outer C-S-H, failing to refine capillary pore, which is amplified by the concomitant AFt shortage, leads to higher capillary adsorption rates. Nevertheless, HDLNPs outperform LP in terms of corrosion protection at equivalent dosage, evoking the LDHs’ unsung ion-exchange capacity in delaying chloride ingress. This advancement in the dispersion of incorporated LDHs underscores their valuable roles in designing durable and sustainable cementitious materials.
期刊介绍:
Cement & concrete composites focuses on advancements in cement-concrete composite technology and the production, use, and performance of cement-based construction materials. It covers a wide range of materials, including fiber-reinforced composites, polymer composites, ferrocement, and those incorporating special aggregates or waste materials. Major themes include microstructure, material properties, testing, durability, mechanics, modeling, design, fabrication, and practical applications. The journal welcomes papers on structural behavior, field studies, repair and maintenance, serviceability, and sustainability. It aims to enhance understanding, provide a platform for unconventional materials, promote low-cost energy-saving materials, and bridge the gap between materials science, engineering, and construction. Special issues on emerging topics are also published to encourage collaboration between materials scientists, engineers, designers, and fabricators.