Conspectus
Porous membranes
are playing paramount roles
in the areas of wastewater
treatment, chemical analysis, energy storage and conversion, flexible
devices, and biomedical engineering. Despite their significance in
the above fields, the performances of the porous membrane will be
weakened due to the inevitable membrane fouling. Solid surfaces or
pores of the membranes are easily contaminated or even clogged due
to the absorption of small molecules or the accumulation of fine particles,
which lower the flux of fluid transport over time, reduce the separation
efficiency, shorten the lifetime of the membranes, and increase the
operational costs. In addition, the defects in membranes also hinder
their applications to some extent. The above-mentioned limitations
all arise from the intrinsic properties of the solid surfaces of the
membranes. To solve these challenges, liquid gating technology was
proposed, which utilizes the capillary-stabilized functional liquid
as a pressure-driven, reversible, and reconfigurable gate to fill
and seal the pores on demand. Using liquid gating technology, multiphase
transportation in the membrane can be modulated with exceptional antifouling
and energy-saving manners due to the defect-free molecular-smooth
liquid interface. Moreover, the further responsive interface design
accelerated the development of liquid gating membranes and their practical
applications to a great extent. In recent years, the concept of the
liquid gating membrane has become a reality through developing various
porous membranes by the rational selection and design of the two essential
parts of the composite membranes: the solid porous matrix and the
gating liquid. These membranes expand the basic scientific issues
of the traditional membranes from the solid–liquid/gas interface
to the solid–liquid–liquid/gas interface and bring more
possibilities for the applications of porous membranes. With properties
and advantages of antifouling, anticorrosion, enhanced transparency,
energy-saving, and stability, these porous membranes have shown various
applications in multiphase separation, biomedical catheters, chemical
detection, mobile valves, microscale flow control, etc.
In this
Account, we provide a systematic review of our group’s
recent progresses in the design and applications of porous membranes
with liquid gating technology. First, we give a comprehensive introduction
to the liquid gating technology, followed by further details on how
to design porous membranes through liquid gating technology and properties
and advantages of the porous membranes. Second, we discuss the applications
of these porous membranes in the fields of multiphase separation,
biomedical catheters, chemical detection, mobile valves, and microscale
flow control. Third, we conclude the Account by describing the current
challenges and future directions of the field.