%0 Online Multimedia
%A Li, Yuzhen
%A Zhang, Guangfa
%A Gao, Ailin
%A Cui, Jian
%A Zhao, Shuai
%A Yan, Yehai
%D 2019
%T Robust
Graphene/Poly(vinyl alcohol) Janus Aerogels with a Hierarchical Architecture
for Highly Efficient Switchable Separation of Oil/Water Emulsions
%U https://acs.figshare.com/articles/media/Robust_Graphene_Poly_vinyl_alcohol_Janus_Aerogels_with_a_Hierarchical_Architecture_for_Highly_Efficient_Switchable_Separation_of_Oil_Water_Emulsions/9905225
%R 10.1021/acsami.9b11277.s002
%2 https://acs.figshare.com/ndownloader/files/17803562
%K energy consumption
%K separation efficiencies
%K J-CGPA
%K wastewater remediation
%K Janus aerogel
%K multifunctional separation materials
%K water-in-oil emulsions
%K cell network
%K freeze-shaping technique
%K novel 3 D Janus aerogel
%K Janus aerogels
%K 3 D
%K superwetting properties
%K Efficient Switchable Separation
%K switchable separation performance
%K rejection efficiency
%K ultrahigh permeation flux
%K water contact angle
%K antithetic sides
%K separation efficiency
%K Hierarchical Architecture
%K WCA
%K Janus Aerogels
%X Given the complexity
and diversity of actual oily sewages, developing multifunctional separation
materials with features of high separation efficiency and low energy
consumption for separating diverse oil/water emulsions is urgently
needed, yet it remains a formidable challenge till now. Herein, a
superior graphene/poly(vinyl alcohol) Janus aerogel (J-CGPA), showing
an intriguing three-dimensional (3D) hierarchical architecture (a
dense skin-layer and a larger internal cell network) and desirable
asymmetric wettability, was exploited via a simple direct freeze-shaping
technique and subsequent mussel-inspired hydrophilic modification.
Benefiting from the controlled unilateral decoration of dopamine,
the resultant aerogels displayed completely opposite superwettability
on two antithetic sides, i.e., one side is highly hydrophobic (water
contact angle (WCA), 143°), whereas the other side is superhydrophilic.
On the basis of the favorable 3D hierarchical structure and binary
cooperative superwetting properties, the Janus aerogels achieved a
remarkable switchable separation performance for both highly emulsified
oil-in-water and water-in-oil emulsions as well as stratified oil/water
mixtures accompanied with outstanding separation efficiencies. Particularly,
an ultrahigh permeation flux of 1306 L m–2 h–1 along with a high rejection efficiency of 99.7% was
acquired solely under the driving of gravity (<1 kPa), which is
1–2 order of magnitude higher than that of pioneering two-dimensional
Janus polymeric/inorganic membranes recently reported. Moreover, together
with robust reusability, this novel 3D Janus aerogel indicates a promising
practical application for high-performance oily wastewater remediation.
%I ACS Publications