Novel Additives to Enhance the Performance of Low Carbon Cements for a Net Zero Future

水泥是混凝土中的“胶水”，是现代文明建立的基础。然而，这带来了巨大的环境成本——水泥生产产生了全球8%的二氧化碳排放量，而从地球上提取的所有材料中有一半用于混凝土。幸运的是，与传统的波特兰水泥（PC）相比，我们正在研究的最近开发的低碳水泥表现出增强的性能，减少了80%的二氧化碳排放，而且几乎完全由工业废料制成。这些水泥需要超塑化共聚物分散剂来改善和易性和流动特性，特别是对于超高性能混凝土。然而，与PC相比，分散剂的行为在每种情况下都有很大不同，这是由于这些胶结物的水固化学性质存在很大差异。新一代低碳水泥迫切需要新型的抗碱高性能分散剂，使其在大规模施工中实际应用。在这个博士项目中，我们将研究这些下一代低碳水泥中有机超塑剂和无机水泥颗粒之间的相互作用，然后利用这些知识来设计性能增强的新型超塑剂。我们将采用一种新的原位表征方法（包括表面特异性技术以及光谱和微观结构表征）来研究有机-无机相互作用的机制和动力学，以及它们对水泥性能的影响。我们将发现控制这些下一代低碳水泥的分散、流化和反应的基本过程，并利用这些知识来设计、合成和测试具有增强性能的新型高效减水剂。这将推动实施和循环经济，帮助水泥生产脱碳，并帮助人类获得缓解气候变化的最佳机会。

Cement is the 'glue' in concrete, the foundation upon which our modern civilisation is built. However, this comes with a huge environmental cost - cement production generates 8% of global CO 2 emissions, and half of all materials extracted from Earth are used in concrete. Luckily, recently developed low-carbon cements that we are investigating exhibit enhanced properties and reduce CO 2 emissions by >80%, compared to traditional Portland cement (PC), and are made almost entirely from industrial wastes. These cements require superplasticising copolymer dispersants to improve workability and flow characteristics, particularly for ultra-high performance concrete. However, dispersant behaviour differs significantly in each case due to extensive differences between aqueous and solid state chemistry in these cements, compared to PC. New alkali-resistant high-performance dispersants are urgently required for these next- generation low-carbon cements to make them practical for use in large-scale construction applications. In this PhD project we will examine the interactions between organic superplasticisers and inorganic cement particles in these next-generation low-carbon cements, and then use this knowledge to design novel superplasticisers with enhanced performance. We will adopt a new in situ characterisation approach (including surface-specific techniques and both spectroscopic and microstructural characterisation) to investigate the mechanisms and kinetics of organic- inorganic interactions, and their effects on cement performance. We will discover the fundamental processes controlling dispersion, fluidisation and reaction of these next-generation low-carbon cements, and use this knowledge to design, synthesise and test novel superplasticisers with enhanced performance. This will drive implementation and a circular economy, help decarbonise cement production, and help give humanity the best possible chance of mitigating climate change.