Osmotic Pumping and Salt Rejection by Polyelectrolyte Hydrogel for Continuous Solar Desalination
Osmotic Pumping and Salt Rejection by Polyelectrolyte Hydrogel for Continuous Solar Desalination
复制标题
DOI：
10.1002/aenm.201900552
复制
发表时间：
2019-08
影响因子：
27.8
通讯作者：
Jian Zeng;Qingyang Wang;Yang Shi;Ping Liu;Renkun Chen
中科院分区：
文献类型：
--
作者：
Jian Zeng;Qingyang Wang;Yang Shi;Ping Liu;Renkun Chen
高效的质量传输和选择性的盐抑制是太阳能或热驱动海水淡化的理想选择，但其实现具有挑战性。本文提出了一种新的液体供应机制，即离子泵效应，使用聚电解质水凝胶泡沫（PHF），并将聚丙烯酸钠[P(SA)]嵌入微孔泡沫碳（CF）中。PHF同时具有用于液体输送的高渗透压和很强的排盐作用。PHF能够维持约24 L / m2 / h （LMH）的高通量，相当于15个太阳下的蒸发通量，并且盐的阻隔率超过80%。与不含聚电解质水凝胶的多孔泡沫碳相比，即只有毛细泵送作用时，由于离子液体泵送效率更高，在单太阳条件下，PHF的蒸发通量提高了42.4%，在DI水中为≈1.6 LMH，在模拟海水中为≈1.3 LMH。更重要的是，由于强烈的拒盐效应，PHF在一个太阳照射下，在72 h内显示出连续稳定的约1.3 LMH的太阳能驱动脱盐通量，这是以前从未实现过的。高效的离子泵送和强大的除盐效果的成功演示使PHF成为可持续太阳能驱动脱盐的有吸引力的平台。
Efficient mass transport and selective salt rejection are highly desirable for solar or thermally driven seawater desalination, but its realization is challenging. Here a new liquid supply mechanism is proposed, i.e., ionic pumping effect, using a polyelectrolyte hydrogel foam (PHF), demonstrated with poly(sodium acrylate) [P(SA)] embedded in a microporous carbon foam (CF). The PHF simultaneously possesses high osmotic pressure for liquid transport and a strong salt‐rejection effect. The PHF is able to sustain high flux of ≈24 L per m2 per hour (LMH), comparable to the evaporative flux under 15 suns, and a salt rejection ratio over 80%. Compared to the porous carbon foam without the polyelectrolyte hydrogel, i.e., with only the capillary pumping effect, the PHF yields a 42.4% higher evaporative flux, at ≈1.6 LMH with DI water and ≈1.3 LMH with simulated seawater under one‐sun condition due to the more efficient ionic liquid pumping. More importantly, thanks to the strong salt‐rejection effect, the PHF shows a continuous and stable solar‐driven desalination flux of ≈1.3 LMH under one‐sun over 72 h, which has not been achieved before. The successful demonstration of both efficient ionic pumping and strong salt rejection effects makes the PHF an attractive platform for sustainable solar‐driven desalination.