posted on 2022-01-24, 15:05authored byHe Yang, Yinghui Sun, Meiwen Peng, Mujin Cai, Bo Zhao, Dan Li, Zhiqiang Liang, Lin Jiang
Developing highly effective salt-resistant
solar evaporators for
a long-term desalination with a high evaporation rate and water production
rate remains a great challenge. Herein, we fabricated a three-dimensional
printed hierarchical porous reduced graphene oxide/carbon black (3DP-HP
rGO/CB) solar evaporator constructed with a thin layer of porous photothermal
interface and a grid of hierarchical porous transport channel possessing
a large-sized porous microstructure. The 3DP-HP rGO/CB solar evaporator
demonstrates a tailored high-salt transport flux of up to 4.3 kg·m–2·h–1, which displays a highly
effective salt-resistant performance at a high evaporation rate of
10.5 kg·m–2·h–1 during
a desalination of 10 wt % NaCl brine under 8 kW·m–2 illumination. Experiments and theoretical calculations prove that
the large porous microstructure with abundant and low-resistance salt
ion channels endows solar evaporators with a high salt transport flux,
therefore boosting salt resistance compared to traditional solar evaporators.
A 10 d desalination experiment shows the long-term salt resistance
of a 3DP-HP rGO/CB solar evaporator for a high-rate and stable evaporation
and water production. Furthermore, the 3DP-HP rGO/CB evaporator can
purify 10 wt % NaCl brine at an ultrafast water production rate of
up to 5.6 L·m–2·h–1 under
natural sunlight. This work demonstrates great potential for the practical
implementation of solar desalination with high productivity.