Deterioration of water quality and the unavailability of drinkable water are pressing challenges worldwide. Removal of toxic organic and inorganic pollutants from water is indispensable for a clean environment, as a response to water scarcity, and for human society. Adsorption-based water technologies are among the most favoured and widely used because of their high efficiency at low-cost, without relying on complicated infrastructure. In recent years, carbon nanomaterials (CNMs), such as graphene and derivatives, carbon nanotubes, carbon nanofibers, nanoporous carbon, fullerenes, graphitic carbon nitride, and nanodiamonds have been extensively exploited as adsorbents due to their extraordinary surface properties, easy modification, large specific surface area, controlled structural varieties, high chemical stability, porosity, low density, ease of regeneration, and reusability. Graphene oxides and other oxidised carbons provide strong acidity and abundant functional groups, and demonstrate excellent adsorption of cationic and basic compounds via electrostatic and hydrogen bonding interactions, while their pristine counterparts exhibit hydrophobic surfaces and offer high adsorption via strong π–π interactions. This review provides a thorough overview of state of the art in CNMs, including significant past and recent advances, as well as future strategies for the use of carbon-based nanoadsorbents in water treatment. This review primarily emphasises the fundamentals of adsorption, its mechanistic aspects, synthesis and properties of CNMs, and adsorption performances of CNMs and their nanocomposites with inorganic and organics materials. Structural engineering and activation processes produce materials with enhanced adsorptive properties and separation efficiencies. Furthermore, the formation of CNMs with 2D and 3D macro-/micro-structures with high porosities is a potential approach to improve adsorption performances and extend CNMs use at the industrial level. This review also addresses some vital issues that persist about these adsorbents, which could shape the future research and industrial application of carbon-based nanoadsorbents in water security.

水质的恶化和饮用水的缺乏是世界范围内的紧迫挑战。对于清洁的环境，对缺水的响应以及对人类社会而言，从水中去除有毒的有机和无机污染物是必不可少的。基于吸附的水技术以其高效率，低成本，不依赖复杂基础设施的优势而成为最受青睐和广泛使用的技术。近年来，由于碳纳米材料具有非凡的表面性能，易改性，大尺寸等优点，因此被广泛地用作吸附剂，例如石墨烯及其衍生物，碳纳米管，碳纳米纤维，纳米多孔碳，富勒烯，石墨碳氮化物和纳米金刚石等碳纳米材料。比表面积，结构受控品种，高化学稳定性，孔隙率，低密度，易于再生，可重复使用。氧化石墨烯和其他氧化碳提供强酸度和丰富的官能团，并通过静电和氢键相互作用显示出对阳离子和碱性化合物的出色吸附，而它们的原始对映体则表现出疏水性表面，并通过强大的π-π相互作用提供了高吸附性。这篇综述全面概述了CNM的最新技术，包括过去和最近的重大进展，以及在水处理中使用碳基纳米吸附剂的未来策略。这篇综述主要着重于吸附的基本原理，其机理方面，CNMs的合成和性质，以及CNMs及其与无机和有机材料的纳米复合材料的吸附性能。结构工程和活化过程产生的材料具有更高的吸附性能和分离效率。此外，形成具有高孔隙率的2D和3D宏观/微观结构的CNM是提高吸附性能并在工业水平上扩展CNM使用的潜在方法。这篇综述还解决了有关这些吸附剂的一些重要问题，这些问题可能会影响碳基纳米吸附剂在水安全领域的未来研究和工业应用。