TY - JOUR
T1 - Form-stable cellulose nanofiber/alginate double-layer aerogel prepared by freeze-assisted structuring and ambient-pressure final drying for solar desalination
AU - Yang, Yuwen
AU - Wu, Zhi
AU - Wang, Kelang
AU - Wang, Jingyi
AU - Liao, Yunrong
AU - Zhang, Zhiming
AU - Chen, Renjie
AU - Pan, Fei
AU - Meng, Wenjun
N1 - Publisher Copyright:
© 2026 Elsevier B.V.
PY - 2026/11/15
Y1 - 2026/11/15
N2 - Sorghum distillers' grains (SDG) are abundant by-product of sorghum liquor production but are often underutilized. In this study, we report a form-stable, carbohydrate-based double-layer aerogel (DLA) fabricated via directional freezing followed by ambient-pressure drying, which avoids energy-intensive supercritical freeze-drying routes. Cellulose nanofibers (CNF) extracted from SDG via TEMPO-mediated oxidation were combined with sodium alginate to form a Ca2+-crosslinked skeleton, and an rGO/g-C3N4 photothermal layer was integrated on top to construct the DLA evaporator. By tuning the rGO/g-C3N4 ratio, A3 (0.6/0.4, w /w) exhibited markedly enhanced dimensional stability during cycling, showing only 3.2% projected-area shrinkage after 10 days, compared with severe shrinkage in the control samples. Meanwhile, A3 maintained efficient solar evaporation with an evaporation rate of 1.43 kg·m−2·h−1 and a photothermal conversion efficiency of 93.14% under simulated irradiation. Outdoor tests further confirmed robust freshwater production across seasons (maximum 2.74 kg·m−2·h−1), and the collected condensate satisfied WHO ion-concentration guidelines. This work demonstrates an ambient-pressure-drying-enabled, form-stable CNF aerogel platform for scalable solar desalination and SDG valorization.
AB - Sorghum distillers' grains (SDG) are abundant by-product of sorghum liquor production but are often underutilized. In this study, we report a form-stable, carbohydrate-based double-layer aerogel (DLA) fabricated via directional freezing followed by ambient-pressure drying, which avoids energy-intensive supercritical freeze-drying routes. Cellulose nanofibers (CNF) extracted from SDG via TEMPO-mediated oxidation were combined with sodium alginate to form a Ca2+-crosslinked skeleton, and an rGO/g-C3N4 photothermal layer was integrated on top to construct the DLA evaporator. By tuning the rGO/g-C3N4 ratio, A3 (0.6/0.4, w /w) exhibited markedly enhanced dimensional stability during cycling, showing only 3.2% projected-area shrinkage after 10 days, compared with severe shrinkage in the control samples. Meanwhile, A3 maintained efficient solar evaporation with an evaporation rate of 1.43 kg·m−2·h−1 and a photothermal conversion efficiency of 93.14% under simulated irradiation. Outdoor tests further confirmed robust freshwater production across seasons (maximum 2.74 kg·m−2·h−1), and the collected condensate satisfied WHO ion-concentration guidelines. This work demonstrates an ambient-pressure-drying-enabled, form-stable CNF aerogel platform for scalable solar desalination and SDG valorization.
KW - Cellulose nanofibers
KW - Dimensional stability
KW - Double-layer aerogel evaporator
KW - Sodium alginate
KW - Solar desalination
UR - https://www.scopus.com/pages/publications/105046181572
U2 - 10.1016/j.desal.2026.120581
DO - 10.1016/j.desal.2026.120581
M3 - Article
AN - SCOPUS:105046181572
SN - 0011-9164
VL - 638
JO - Desalination
JF - Desalination
M1 - 120581
ER -