photovoltaic cells. Such phononic band gap structures may be achieved by BCP
SA. However, it is not yet obvious to relate the thermalization in photovoltaics with
phonon formation. Thus, more in-depth studies have to be performed to assess
whether this strategy can be successful.
6.5 Membranes
Membranes can be defined as selective barriers between two phases and have a
plethora of applications, including water purification, desalination, drug development,
and chemical sensing. BCP SA can be a useful approach for membrane fabrication
because tunable structure and narrow size control of membrane pores is possible.
Yang et al. synthesized a thin film with an ordered standing cylinder structure
from BCP SA and transferred the film to a porous support to fabricate highly
selective membranes with ordered nanochannels for virus filtration [70]. The top
thin layer derived from BCP SA provided size-selective pores at the nanoscale.
While very creative, the approach by Yang et al. required several tedious steps for
membrane formation, thus making large-scale fabrication challenging. As discussed
in Sect. 4, Peinemann et al. proposed an innovative approach (now referred to as
SNIPS) that combined NIPS, a well-established process in the membrane industry,
with BCP SA to fabricate asymmetric BCP-derived membranes (see Fig. 7) [45].
The membranes exhibit well-ordered, densely packed, and uniform pores in the
top surface and a substructure with graded porosity. SNIPS provides a scalable
fabrication process of asymmetric BCP membranes with high size selectivity for
nanometer-sized solutes.
The Wiesner group applied the SNIPS process to poly(isoprene-b-styreneb-4-vinyl pyridine) terpolymer to fabricate scalable membranes with high fluxes
and sharp molecular weight cut-offs [47]. Introduction of the third, PI block
generated membranes with improved mechanical properties over the diblock
copolymer-based materials studied by Peinemann et al. Thus, besides BCP SA as
a means to control structure, BCP architectures can further be employed to control
the mechanical properties of nanomaterials.
6.6 Lithium Battery
Lithium batteries can benefit from nanostructured electrodes (i.e., anode and cathode)
that combine large electric capacity by accommodating as many lithium ions as
possible with short diffusion paths. The most widely used anode material is graphite,
where lithium ions intercalate between graphite layers. A battery with lithium ions
chemically intercalated in an anode composed of a non-lithium material is usually
called a lithium ion battery. In order to improve battery capacity, lithium metal has
been studied as anode material. A battery with lithium metal anode is called a lithium
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K. Hur and U. Wiesner
SA. However, it is not yet obvious to relate the thermalization in photovoltaics with
phonon formation. Thus, more in-depth studies have to be performed to assess
whether this strategy can be successful.
6.5 Membranes
Membranes can be defined as selective barriers between two phases and have a
plethora of applications, including water purification, desalination, drug development,
and chemical sensing. BCP SA can be a useful approach for membrane fabrication
because tunable structure and narrow size control of membrane pores is possible.
Yang et al. synthesized a thin film with an ordered standing cylinder structure
from BCP SA and transferred the film to a porous support to fabricate highly
selective membranes with ordered nanochannels for virus filtration [70]. The top
thin layer derived from BCP SA provided size-selective pores at the nanoscale.
While very creative, the approach by Yang et al. required several tedious steps for
membrane formation, thus making large-scale fabrication challenging. As discussed
in Sect. 4, Peinemann et al. proposed an innovative approach (now referred to as
SNIPS) that combined NIPS, a well-established process in the membrane industry,
with BCP SA to fabricate asymmetric BCP-derived membranes (see Fig. 7) [45].
The membranes exhibit well-ordered, densely packed, and uniform pores in the
top surface and a substructure with graded porosity. SNIPS provides a scalable
fabrication process of asymmetric BCP membranes with high size selectivity for
nanometer-sized solutes.
The Wiesner group applied the SNIPS process to poly(isoprene-b-styreneb-4-vinyl pyridine) terpolymer to fabricate scalable membranes with high fluxes
and sharp molecular weight cut-offs [47]. Introduction of the third, PI block
generated membranes with improved mechanical properties over the diblock
copolymer-based materials studied by Peinemann et al. Thus, besides BCP SA as
a means to control structure, BCP architectures can further be employed to control
the mechanical properties of nanomaterials.
6.6 Lithium Battery
Lithium batteries can benefit from nanostructured electrodes (i.e., anode and cathode)
that combine large electric capacity by accommodating as many lithium ions as
possible with short diffusion paths. The most widely used anode material is graphite,
where lithium ions intercalate between graphite layers. A battery with lithium ions
chemically intercalated in an anode composed of a non-lithium material is usually
called a lithium ion battery. In order to improve battery capacity, lithium metal has
been studied as anode material. A battery with lithium metal anode is called a lithium
288
K. Hur and U. Wiesner