▎ 摘　　要

In this study, we designed a mesoporous composite with high latent heat capacity, stable structure, and efficient thermal response for thermal energy storage in green building constructions. Graphene oxide (GO) nanosheets were sandwiched by a vertically interconnected network of two-dimensional (2D) calcium silicate hydrate (CSH) nanoplates via an in situ dissolution-coprecipitation strategy to obtain CSH/GO/CSH (CGC). The CGC mesoporous sandwich-like structures with a high specific surface area (677 m(2) g(-1)) and a large pore volume (similar to 2.5 cm(3) g(-1)) were infiltrated with lauric acid (LA) as phase change materials (PCMs) to produce LA@CGC composites. Our results demonstrated that LA@CGC had a high latent heat value of 118.0-127.6 J g(-1) and 92-99% efficiency after 50 heating-cooling cycles, which, together with the reinforcing properties of GO and the compatibility of CSH in cement-based matrixes, makes the composite a sustainable PCM for thermal energy storage in building constructions.