Covalent organic frameworks (COFs) are an exciting class of porous materials that have been explored as energy-storage materials for more than a decade. This review discusses efforts to develop these materials for applications in gas and electrical power storage. Some of the design strategies for developing the gas sorption properties of COFs and mechanistic studies on their formation are also discussed.

In this communication, we report an azine linked covalent organic framework based on a six-fold symmetric hexphenylbenzene (HEX) monomer functionalized with aldehyde groups. HEX-COF 1 has an average pore size of 1 nm, a surface area in excess of 1200 m(2) g(-1) and shows excellent sorption capability for carbon dioxide (20 wt%) and methane (2.3 wt%) at 273 K and 1 atm.

Breast cancer metastasis is the major cause of cancer death in women worldwide. Early detection would save many lives, but current fluorescence imaging probes are limited in their detection ability, particularly of bone and liver micrometastases. Herein, probes that are capable of imaging tiny (<1 mm) micrometastases in the liver, lung, pancreas, kidneys, and bone, that have disseminated from the primary site, are reported. The influence of the poly(ethylene glycol) (PEG) chain length on the performance of water-soluble, pH-responsive, near-infrared 4,4'-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) probes is systematically investigated to demonstrate that PEG tuning can provide control over micrometastasis tracking with high tumor-to-background contrast (up to 12/1). Optimized probes can effectively visualize tumor boundaries and successfully detect micrometastases with diameters <1 mm. The bone-metastasis-targeting ability of these probes is further enhanced by covalent functionalization with bisphosphonate. This improved detection of both bone and liver micrometastases (<2 mm) with excellent tumor-to-normal contrast (5.2/1). A versatile method is thus introduced to directly synthesize modular water-soluble probes with broad potential utility. Through a single intravenous injection, these materials can image micrometastases in multiple organs with spatiotemporal resolution. They thus hold promise for metastasis diagnosis, image-guided surgery, and theranostic PEGylated drug therapies.

We report the synthesis of one new boronate ester-based covalent organic framework (COF) and two new covalent organic polymers (COPs) made with fluoranthene-containing monomers and hexahydroxytriphenylene. The structure of the monomer heavily influences whether this material forms a highly ordered mesoporous material (COF) or an amorphous, microporous material (COP). The synthesis of the fluoranthene monomers was carried out using a divergent strategy that allows for systematic structural variation and the ability to conduct a careful structure-function study. We found that small structural variations in the monomers dramatically affected the crystallinity, surface area, pore structure, and luminescence properties of the polymers. While each of the monomers contains the same fluoranthene core, the resultant pore sizes range from microporous (10 Å) to mesoporous (37 Å), with surface areas ranging from ∼500 to 1200 m/g. To help explain how these small structural differences can have such a large effect, we carried out a series of molecular dynamics simulations on the polymers to obtain information with atomic-scale resolution on how the monomer structure affects non-covalent COF layer stacking.