Confined materials have been extensively studied to improve energy efficiency and mitigate environmental degradation due to their confinement effect. Compared with other methods of preparing confined materials, the coating method has the advantages of versatility and high efficiency. Although SiO₂ NT confined materials have been widely used in thermal catalysis, few review articles have summarized this content. Additionally, preparation techniques for one-dimensional (1D) carbon confined materials using various carbon precursors and their energy storage applications have not been thoroughly discussed. Therefore, in this paper, we first introduce the synthesis examples and discuss critical factors influencing the successful coating of various host precursors upon the surface of guest materials. Then, their thermal catalysis and energy storage applications are analyzed and discussed together with the reasons which result in their excellent performance. Finally, potential research directions of designing 1D confined materials are formulated to motivate researchers and promote their energy and environmental applications.

Concrete is vital for the development of modern buildings. However, they suffer from the high viscosity problem in their application process due to the use of a low water–cement ratio in order to maintain their high strength. Developing PCEs with the presence of ester functional groups in their molecular structure is one of the most effective measures to improve the flowability of concrete. Here, three PCEs with different alkyl densities of acrylic acid ester: PCE-M, PCE-E, and PCE-B were designed to explore their viscosity-reducing effect on the performance of cement and concrete. The structures of the three PCEs were characterized via Fourier transform infrared (FTIR) spectra, proton nuclear magnetic resonance (¹H NMR), and gel permeation chromatography (GPC). Their properties were also determined via zeta potential, surface tension, and rheological experiments. It was found that PCE-M had the best performance, with the lowest surface tension, highest zeta potential, and therefore highest charge density on the cement particles, lowest viscosity, and highest flowability of cement paste, and exhibited the best performance of concrete in terms of workability. The best performance of PCE-M in reducing the viscosity of cement and concrete can be ascribed to the smallest amount of water-repellent alkyl groups, enhancing the electrostatic repulsion and reducing the viscosity, thereby boosting the dispersion and stabilization of cement pastes and concrete. This study shed lights on designing other PCEs with high viscosity-reducing effects via an ester group control.