Light-operated materials have gained significant attention for their potential technological importance. To achieve molecular motion within extended networks, stimuliresponsive units require free space. The majority of the so far reported 2D-extended organic networks with responsive moieties restrict their freedom of motion on account of their connectivity providing constrained free volume for efficient molecular motion. We report here a light-responsive azobenzene-functionalized covalent organic framework (TTA-AzoDFP) designed in a way that the pendent azobenzene groups are pointing toward the pore channels with sufficient free volume necessary for the unencumbered dynamic motion to occur inside the pores of the covalent organic framework (COF) and undergo a reversible trans−cis photoisomerization upon light irradiation. The resulting hydrophobic COF was used for the storage of rhodamine B and its controlled release in solution by the mechanical motion of the azobenzene units triggered by ultraviolet-light irradiation. The TTA-AzoDFP displayed unprecedented photoregulated fluorescence emission behavior upon UV-light irradiation. Size, emission, and degree of hydrophobicity with respect to trans−cis−trans photoisomerization could be reversibly controlled by alternating UV-and visible-light exposure. The results reported here demonstrate once again the importance of the careful design of the linkers not only to allow the incorporation of molecular switches within the chemical structure of COFs but also to provide the required free space for not hindering their motion. The results demonstrate that responsive COFs could be suitable platforms for delivery systems that can be controlled by external stimuli.

A superhydrophobic porous covalent polymer with a calix[4]arene backbone was synthesized and shown to efficiently remove oil, organic solvents and toxic dyes from aqueous mixtures.

The immobilization of molecular switches within materials can give rise to new bulk properties that are useful for a variety of applications.

We present the synthesis of a silver nanoparticle (AgNP) based drug-delivery system that achieves the simultaneous intracellular delivery of doxorubicin (Dox) and alendronate (Ald) and improves the anticancer therapeutic indices of both drugs.

Hexagonal‐shaped nanoplates (HNPs) of MoS2 on vertically aligned carbon nanotubes (CNTs) over a patterned area (a circular area of 1 cm2 diameter) are produced by chemical vapor deposition technique. With an optimized initial Mo film thickness, a uniform coverage of MoS2 HNPs with a thickness around 20 nm is achieved. The results confirm that the CNT template plays an important role in the MoS2 HNPs growth. Each MoS2 HNP consists of abundant exposed edges, interesting for sensing and catalysis applications. High crystallinity and quality of the as‐produced material are revealed by X‐ray photoelectron and Raman spectroscopies. Furthermore, NO2 gas‐sensing studies show better sensitivity and recovery for MoS2/CNT samples as compared to pristine CNTs. The detection of NO2 gas in a few tens of parts per million to a few hundreds of parts per billion range, at room temperature, is achieved. Density‐functional theory calculation indicates that the exposed edges of MoS2 play a significant role in the NO2 sensing as compared to horizontally aligned MoS2 layers. The present report can promote the research toward the fabrication of efficient and reliable MoS2‐based hybrid materials for toxic gas‐sensing applications for air quality monitoring in various environments.