5 research outputs found
Chiral Reticular Chemistry: A Tailored Approach Crafting Highly Porous and Hydrolytically Robust MetalâOrganic Frameworks for Intelligent Humidity Control
Control
of humidity within confined spaces is critical for maintaining
air quality and human well-being, with implications for environments
ranging from international space stations and pharmacies to granaries
and cultural relic preservation sites. However, existing techniques
rely on energy-intensive electrically driven equipment or complex
temperature and humidity control (THC) systems, resulting in imprecision
and inconvenience. The development of innovative techniques and materials
capable of simultaneously meeting the stringent requirements of practical
applications holds the key to creating intelligent and energy-efficient
humidity control devices. In this study, we introduce chiral reticular
chemistry as a tailored synthetic approach, targeting a highly porous hea topological framework characterized by intrinsic interpenetrating
pore architecture. This groundbreaking design successfully circumvents
the traditional compromise between the pore volume and hydrolytic
stability. Our metalâorganic framework (MOF) exhibits an extraordinary
working capacity, setting a new record at 1.35 g gâ1 within the relative humidity (RH) range of 40â60%, without
exhibiting hysteresis. Consequently, it emerges as a state-of-the-art
candidate for intelligent humidity regulation within confined spaces.
Utilizing single-crystal X-ray measurements and molecular simulations,
we unequivocally elucidate the mechanism of water clustering and pore
filling, underscoring the pivotal role of the linker functionality
in governing the water seeding process. Our findings represent a significant
advancement in the field, paving the way for the development of highly
efficient humidity control technologies and offering promising solutions
for diverse real-world scenarios
Chiral Reticular Chemistry: A Tailored Approach Crafting Highly Porous and Hydrolytically Robust MetalâOrganic Frameworks for Intelligent Humidity Control
Control
of humidity within confined spaces is critical for maintaining
air quality and human well-being, with implications for environments
ranging from international space stations and pharmacies to granaries
and cultural relic preservation sites. However, existing techniques
rely on energy-intensive electrically driven equipment or complex
temperature and humidity control (THC) systems, resulting in imprecision
and inconvenience. The development of innovative techniques and materials
capable of simultaneously meeting the stringent requirements of practical
applications holds the key to creating intelligent and energy-efficient
humidity control devices. In this study, we introduce chiral reticular
chemistry as a tailored synthetic approach, targeting a highly porous hea topological framework characterized by intrinsic interpenetrating
pore architecture. This groundbreaking design successfully circumvents
the traditional compromise between the pore volume and hydrolytic
stability. Our metalâorganic framework (MOF) exhibits an extraordinary
working capacity, setting a new record at 1.35 g gâ1 within the relative humidity (RH) range of 40â60%, without
exhibiting hysteresis. Consequently, it emerges as a state-of-the-art
candidate for intelligent humidity regulation within confined spaces.
Utilizing single-crystal X-ray measurements and molecular simulations,
we unequivocally elucidate the mechanism of water clustering and pore
filling, underscoring the pivotal role of the linker functionality
in governing the water seeding process. Our findings represent a significant
advancement in the field, paving the way for the development of highly
efficient humidity control technologies and offering promising solutions
for diverse real-world scenarios
Programmed Polarizability Engineering in a Cyclen-Based Cubic Zr(IV) MetalâOrganic Framework to Boost Xe/Kr Separation
Efficient
separation of xenon (Xe) and krypton (Kr) mixtures through
vacuum swing adsorption (VSA) is considered the most attractive route
to reduce energy consumption, but discriminating between these two
gases is difficult due to their similar properties. In this work,
we report a cubic zirconium-based MOF (Zr-MOF) platform, denoted as
NU-1107, capable of achieving selective separation of Xe/Kr by post-synthetically
engineering framework polarizability in a programmable manner. Specifically,
the tetratopic linkers in NU-1107 feature tetradentate cyclen cores
that are capable of chelating a variety of transition-metal ions,
affording a sequence of metal-docked cationic isostructural Zr-MOFs.
NU-1107-Ag(I), which features the strongest framework polarizability
among this series, achieves the best performance for a 20:80 v/v Xe/Kr
mixture at 298 K and 1.0 bar with an ideal adsorbed solution theory
(IAST) predicted selectivity of 13.4, placing it among the highest
performing MOF materials reported to date. Notably, the Xe/Kr separation
performance for NU-1107-Ag(I) is significantly better than that of
the isoreticular, porphyrin-based MOF-525-Ag(II), highlighting how
the cyclen core can generate relatively stronger framework polarizability
through the formation of low-valent Ag(I) species and polarizable
counteranions. Density functional theory (DFT) calculations corroborate
these experimental results and suggest strong interactions between
Xe and exposed Ag(I) sites in NU-1107-Ag(I). Finally, we validated
this framework polarizability regulation approach by demonstrating
the effectiveness of NU-1107-Ag(I) toward C3H6/C3H8 separation, indicating that this generalizable
strategy can facilitate the bespoke synthesis of polarized porous
materials for targeted separations
Rationally Tailored Mesoporous Hosts for Optimal Protein Encapsulation
Proteins play important roles in the therapeutic, medical
diagnostic,
and chemical catalysis industries. However, their potential is often
limited by their fragile and dynamic nature outside cellular environments.
The encapsulation of proteins in solid materials has been widely pursued
as a route to enhance their stability and ease of handling. Nevertheless,
the experimental investigation of protein interactions with rationally
designed synthetic hosts still represents an area in need of improvement.
In this work, we leveraged the tunability and crystallinity of metalâorganic
frameworks (MOFs) and developed a series of crystallographically defined
protein hosts with varying chemical properties. Through systematic
studies, we identified the dominating mechanisms for protein encapsulation
and developed a host material with well-tailored properties to effectively
encapsulate the protein ubiquitin. Specifically, in our mesoporous
hosts, we found that ubiquitin encapsulation is thermodynamically
favored. A more hydrophilic encapsulation environment with favorable
electrostatic interactions induces enthalpically favored ubiquitinâMOF
interactions, and a higher pH condition reduces the intraparticle
diffusion barrier, both leading to a higher protein loading. Our findings
provide a fundamental understanding of hostâguest interactions
between proteins and solid matrices and offer new insights to guide
the design of future protein host materials to achieve optimal protein
loading. The MOF modification technique used in this work also demonstrates
a facile method to develop materials easily customizable for encapsulating
proteins with different surface properties
Optical, Electronic, and Magnetic Engineering of âš111â© Layered Halide Perovskites
Antimony
and bismuth âš111â© layered perovskites have
recently attracted significant attention as possible, nontoxic alternatives
to lead halide perovskites. Unlike lead halide perovskites, however,
âš111â© halide perovskites have shown limited ability
to tune their optical and electronic properties. Herein, we report
on the metal alloying of manganese and copper into the family of materials
with formula Cs<sub>4</sub>Mn<sub>1â<i>x</i></sub>Cu<sub><i>x</i></sub>Sb<sub>2</sub>Cl<sub>12</sub> (<i>x</i> = 0â1). By changing the concentration of manganese
and copper, we show the ability to modulate the bandgap of this family
of compounds over the span of 2 electron volts, from 3.0 to
1.0 eV. Furthermore, we show that in doing so, we can also adjust
other relevant properties such as their magnetic behavior and their
electronic structure