Modular solar interfacial evaporation and crystallization– Functional partitioning

Solar-driven interfacial evaporation stands out as a low-energy, environmentally-friendly desalination approach with substantial potential for clean water recovery and resource harvesting. However, the stability of the system is compromised by an undesirable increase in salt accumulation. Herein, we designed a modular structure to separate functional areas. The whole structure contains an evaporator and a collector: the evaporator mainly takes on the function of evaporation and the collector is mainly used for the crystals collection. Operating under one sun illumination, the system attained a high evaporation rate of 2.34 kg m -2 h −1 and a high solar-water evaporation efficiency of 133.19 %. Owing to the replaceable collector, the evaporation system maintained a consistently high evaporation rate even after 240 h of continuous operation, and up to 97 % of the solute was enriched in the collector. Furthermore, we investigated the impact of natural organic matter (NOM) on both evaporation and crystallization within the system. This study provides a new perspective on the design of solar interfacial evaporation and crystallization systems.