University of North Texas 
Journal Authors:
Y. She, J. Lee, B. Diroll, T. Scharf, E. Shevchenko, D. Berman
Abstract
Inorganic nanoporous materials with highly accessible pores are of great interest
for the design of efficient catalytic, purification and detection systems. Limited
access to the pores is a common problem associated with traditional approaches for
the synthesis of porous materials, affecting the functionality of the low-density
structure. Recently, infiltration of a nanoporous polymer template with inorganic
precursors followed by oxidative annealing was proposed as a new and efficient approach
to creating porous inorganic structures with controlled thickness, composition and
pore sizes. Here, we report an ultra-high accessibility of the pores in porous films
prepared via polymer-swelling-assisted sequential infiltration synthesis (SIS). Using
a quartz crystal microbalance technique, we show the increased solvent adsorbing capabilities
of highly porous alumina films as a result of high interconnectivity of the pores
in such structures. The directionality and highly interconnected nature of the pores
are demonstrated in experiments with the partial blocking of pore access by the deposition
of a single-layer graphene that is not transparent to solvent. 60% of the pores remain
accessible when only 20% of the surface is exposed to solvent. Using humidity detection
as an example, we also show that highly porous alumina produced by polymer-swelling-assisted
SIS is a promising candidate for sensing applications.
Y. She, J. Lee, B. Diroll, T. Scharf, E. Shevchenko, D. Berman*: “Accessibility of the pores in highly porous alumina films synthesized via sequential infiltration synthesis”, Nanotechnology 29, 49 (2018), https://doi.org/10.1088/1361-6528/aae144