Disclaimer: The English translation of this press release is provided for informational purposes only. In the event of any discrepancy, inconsistency, or difference in interpretation between this translation and the original Chinese version, the original Chinese version shall prevail.

This press release was issued by the Northeast Forestry University and provides a summary of a scientific article published in the Journal “Nature Communications” under https://doi.org/10.1038/s41467-026-72723-y

Recently, the teams led by Professors Chengyu Wang and Haiyue Yang from the Key Laboratory of Bio-Based Material Science and Technology of the Ministry of Education at Northeast Forestry University, in collaboration with Professor Ruzhu Wang’s team at Shanghai Jiao Tong University, published a research article entitled “Hygroscopic Wood Sponge with Dual Phase Change Function for Enhanced All-Weather Atmospheric Water Harvesting” in the internationally renowned multidisciplinary journal Nature Communications.

The study proposes a design strategy for a hygroscopic wood-sponge composite with dual phase-change functionality. Using the vertically aligned, hierarchical channels found in natural wood, the researchers constructed a rapid water-sorption zone loaded with lithium chloride. They also incorporated a phase-change photothermal hydrogel as an energy-management zone.

This design creates a synergistic coupling between the phase transition of water during the sorption–desorption process and the storage and release of heat by the phase-change material. Consequently, the system can continue promoting water release under weak sunlight and even in darkness, demonstrating significant potential for all-weather, passive and efficient atmospheric water harvesting.

Atmospheric water harvesting is an important strategy for alleviating freshwater shortages in off-grid and arid regions, as well as in areas with inadequate water infrastructure. However, existing sorption-based atmospheric water-harvesting materials generally suffer from high resistance to water-vapour diffusion, slow sorption kinetics and solar-driven desorption processes that are strongly affected by day–night cycles and fluctuations in weather conditions.

In this study, the hierarchical open channels of the wood sponge reduce resistance to water-vapour transport. Meanwhile, the phase-change photothermal hydrogel stores and releases solar thermal energy, effectively improving the material’s capacity for continuous water production under complex environmental conditions.

The results show that the material achieved a water uptake of 0.59–3.03 g g⁻¹ across a relative-humidity range of 15%–90% and reached sorption equilibrium within 360 minutes. The phase-change photothermal hydrogel exhibited a thermal-storage enthalpy of 155.51 J g⁻¹ and an energy-conversion efficiency of 90.80%.

Under different climatic conditions—including summer conditions in Harbin and winter conditions in Xiamen—the material arrays produced 0.96–1.72 L kg⁻¹ day⁻¹ of water. The collected water samples met the relevant World Health Organization standards for drinking water.

This study provides a new material-design approach for developing stable, efficient and sustainable atmospheric water-harvesting systems.

Scientific article: Hygroscopic wood sponge with dual phase change function for enhanced all-weather atmospheric water harvesting