Synthesis of covalent organic frameworks (COFs) with desirable organic units furnishes advanced materials with unique functionalities. As an emerging class of twodimensional (2D) COFs, sp 2 -carbon-conjugated COFs provide a facile platform to build highly stable and crystalline porous polymers. Herein, a 2D olefin-linked COF was prepared by employing nanographene, namely, dibenzo-[hi,st]ovalene (DBOV), as a building block. The DBOV-COF exhibits unique ABC-stacked lattices, enhanced stability, and charge-carrier mobility of � 0.6 cm 2 V À 1 s À 1 inferred from ultrafast terahertz photoconductivity measurements. The ABC-stacking structure was revealed by the high-resolution transmission electron microscopy and powder X-ray diffraction. DBOV-COF demonstrated remarkable photocatalytic activity in hydroxylation, which was attributed to the exposure of narrow-energy-gap DBOV cores in the COF pores, in conjunction with efficient charge transport following light absorption.

Biocatalysis has become a powerful tool in synthetic chemistry, where enzymes are used to produce highly selective products under mild conditions. Using photocatalytically regenerated cofactors in synergistic combination with enzymes in a cascade fashion offers an efficient synthetic route to produce specific compounds. However, the combination of enzymes and photocatalysts has been limited due to the rapid degradation of the biomaterials by photogenerated reactive oxygen species, which denature and deactivate the enzymatic material. Here, we design core–shell structured porous nano-photoreactors for highly stable and recyclable photobiocatalysis under aerobic conditions. The enzymatic cofactor NAD + from NADH can be efficiently regenerated by the photoactive organosilica core, while photogenerated active oxygen species are trapped and deactivated through the non-photoactive shell, protecting the enzymatic material. The versatility of these photocatalytic core–shell nanoreactors was demonstrated in tandem with two different enzymatic systems, glycerol dehydrogenase and glucose 1-dehydrogenase, where long-term enzyme stability was observed for the core–shell photocatalytic system.

N‐heterocyclic compounds demonstrate wide applications ranging from natural compound production to coordination chemistry. Usually, the synthesis of N‐heterocyclic compounds is conducted under thermal conditions, mostly by Lewis acids or metal‐containing compounds as molecular catalysts. Here, we report a photocatalytic route for aryl azoline formation by mesoporous organosilica as visible light‐active and heterogeneous photocatalyst. Via formation of aromatic aldehydes with various amines, 2‐phenyl‐2‐imidazoline, 2‐phenyl‐2‐oxazoline, 2‐phenyl‐2‐thiazoline and their derivatives could be formed with high conversion and selectivity. Additionally, the organosilica photocatalyst showed high stability and reusability.

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Using polymeric photocatalytic materials for visible lightdriven heterogeneous conversion of organic substances in environmentally benign reaction media as in water, in particular, has gained much attention recently. Most of the current conjugated polymer photocatalysts are often unsuitable for applications in water because of their highly hydrophobic nature. Classical polymer-based photocatalysts possess advantages that include precise control of properties through facile synthesis and direct access to the toolbox of classical polymer chemistry. However, the effect of monomer composition remains unclear, and a systematic investigation of structure−property relationships is still missing. In this work, we design water-compatible poly(methyl methacrylate) (PMMA)-based polymer photocatalysts by precise control of comonomers with specific functions. The electronic and optical properties and water compatibility of PMMA photocatalysts could be tuned, and they showed direct dependence on the monomer composition. Mathematical as well as density functional theory simulation as hydration enthalpy calculations supported the observed effects. The photocatalytic degradation of 2,4-dichlorophenol in water as model reaction showed an optimum of polymer composition and solubility for the photocatalytic reactivity. More remediation of important contaminants was successfully conducted as diethyl phthalate, acetophenone, and bisphenol-A, which are common products from plastic degradation detected in groundwater.