{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,5]],"date-time":"2026-11-05T13:19:39Z","timestamp":1793884779841,"version":"4.7.0"},"reference-count":44,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T00:00:00Z","timestamp":1787184000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"CHN Energy Shendong Coal Group \u201cCHN Shenhua Energy Co., Ltd. Shendong Coal Branch\u201d","award":["E210100775"],"award-info":[{"award-number":["E210100775"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>High-performance alkali-free accelerators require a mechanistic understanding of interactions between inorganic accelerants and organic modifiers. Although aluminum sulfate (AS) promotes rapid ettringite (AFt) formation, uncontrolled crystallization leads to coarse microstructures and instability from AFt-to-AFm conversion. Here, a molecular-scale synergistic mechanism is identified in which an amide regulates AS-driven hydration. The amide controls nucleation and growth of AFt and C\u2013S\u2013H via chemisorption on C3A\/C3S and complexation with Ca2+. Within the tested mixing proportions, the high-aluminum-sulfate and moderate-amide combination achieves the highest early strength (17.05 MPa at 1 day) via constructing an interlocked AFt\/C\u2013S\u2013H skeleton, whereas excessive amide suppresses crystallization and low AS accelerates AFt-to-AFm conversion, reducing long-term performance. In-situ XRD, thermal analysis, and microscopy confirm a denser, more stable microstructure (27.37 MPa at 10 days) with minimal 28-day strength loss (17.38 MPa). Density functional theory shows an adsorption hierarchy of amide &gt; AS species &gt; H2O, explaining its dominant surface-modifying role. This study provides a framework for designing cement accelerators with balanced early strength and durability.<\/jats:p>","DOI":"10.3390\/ma19163538","type":"journal-article","created":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T16:05:19Z","timestamp":1787241919000},"page":"3538","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Molecular-Scale Regulation of Cement Hydration and Microstructure via Synergistic Aluminum Sulfate\u2013Amide Interactions"],"prefix":"10.3390","volume":"19","author":[{"given":"Chuanjiu","family":"Zhang","sequence":"first","affiliation":[{"name":"School of Resources and Safety Engineering, Chongqing University, Chongqing 400044, China"},{"name":"China Energy Shendong Coal Group Co., Ltd., Ordos 017200, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jie","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Resources and Safety Engineering, Chongqing University, Chongqing 400044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hu","family":"Chen","sequence":"additional","affiliation":[{"name":"CCTEG Wuhan Engineering Company, Wuhan 430064, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peng","family":"Li","sequence":"additional","affiliation":[{"name":"China Energy Shendong Coal Group Co., Ltd., Ordos 017200, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kaiwen","family":"Shi","sequence":"additional","affiliation":[{"name":"School of Resources and Safety Engineering, Chongqing University, Chongqing 400044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fei","family":"Gao","sequence":"additional","affiliation":[{"name":"School of Resources and Safety Engineering, Chongqing University, Chongqing 400044, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xuanliang","family":"Li","sequence":"additional","affiliation":[{"name":"China Energy Shendong Coal Group Co., Ltd., Ordos 017200, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qiangqiang","family":"Hu","sequence":"additional","affiliation":[{"name":"China Energy Shendong Coal Group Co., Ltd., Ordos 017200, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Meng","family":"Li","sequence":"additional","affiliation":[{"name":"College of Energy and Mining Engineering, Xi\u2019an University of Science and Technology, Xi\u2019an 710054, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"129673","DOI":"10.1016\/j.conbuildmat.2022.129673","article-title":"A novel early strength agent prepared by wet-grinding concrete waste slurry and its effect on early hydration and mechanical properties of cement based materials","volume":"362","author":"Su","year":"2023","journal-title":"Constr. 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