Recent advances in cellulose-based solar interfacial evaporators enabled by hydrogen-bond network regulation

Interfacial solar steam evaporation (ISSE) is governed not only by photothermal conversion, but also by how water is organized, transported and released at the evaporative interface. Cellulose is well suited to this process not only because it is rich in hydroxyl groups but also it is abundant, low-cost, and renewable. These features allow cellulose to influence hydrogen-bond environments, hydration layers, and interfacial water states, while its hierarchical porous structures support water supply and vapor release. This review summarizes recent progress in cellulose-based ISSE with an emphasis on hydrogen-bond-network regulation. Such nanoconfined interfaces tune interfacial water states and decrease the apparent enthalpy evaporation behavior. We summarize how cellulose affects water populations related to evaporation pathways, and how high evaporation flux can be understood in terms of interfacial kinetics and system-level heat and mass exchange. We also discuss how these interfacial effects are translated into device design and operation. By linking cellulose-water hydrogen-bond regulation with device-level evaporation design, this review provides a molecular-to-device perspective for developing low-cost and stable solar evaporators.