The increasing amount of CO2 in the atmosphere
is recognized
as a major cause of global warming and its harmful consequences. Industrially,
CO2 is captured by chemisorption using amine-based solvents.
However, there are major drawbacks to the wet-scrubbing process, including
corrosion and high regeneration energy. The physical adsorption of
CO2 by using porous solid adsorbents is a viable and efficient
alternative. Therefore, designing effective porous polymers with microporosity
and polar functional groups using a simple approach is important for
efficient carbon dioxide capture. This work describes the design,
characterization, and CO2 capture studies of a 3D-triptycene
and phenanthroline-based microporous polymer (TPPM). The polymeric
framework of TPPM is incorporated with 3D triptycene and phenanthroline
as robust motifs to yield inflexible, twisted polymeric frameworks
with an abundance of micropores and ultramicropores. This confers
desirable features such as higher surface area, abundance microporosity,
and physiochemical and thermal stability. TPPM demonstrated excellent
thermal stability (T
d > 380 °C)
with
a larger BET-specific surface area of 1120 m2 g–1 and considerable microporosity, which makes it a promising adsorbent
for CO2 capture applications. The Morphological characterization
of the polymer sample shows the formation of microspheres with diameters
around 0.5–1 μm. TPPM has a strong affinity for CO2 with Q
st of 23 kJ mol–1 demonstrating promising CO2 capture capacity of 2.76
mmol g–1 at 273 K and 1.85 mmol g–1 at 298 K where the micropore volume (V
mic = 0.445 cm3 g–1) plays a potential
role. The CO2 capture capacity of TPPM outperforms several
other literature-reported porous polymers. TPPM also demonstrated
promising CO2 selectivity over CH4 and N2, suggesting good promise for CO2 adsorption and
separation.