Polyfunctional Conjugated Microporous Polymers for Applications in Direct C-H Arylation of Unactivated Arenes and Aqueous Adsorption of Aromatic Amines

Adsorption and photocatalytic applications of porphyrin-based materials for environmental separation processes: A review

As society progresses and industrializes, the issue of water pollution, caused by a wide array of organic and inorganic pollutants, poses significant risks to both human well-being and the environment. Given its distinctive characteristics, water pollution has become a paramount concern for society, necessitating immediate attention. Numerous studies have been conducted on wastewater treatment, primarily focusing on two key approaches: adsorption and photocatalytic degradation. Adsorption offers unparalleled advantages, including its simplicity, high removal efficiency, and cost-effectiveness. Conversely, photocatalysis harnesses abundant, clean, and non-polluting sunlight, addressing the critical issue of energy scarcity. Porphyrins, which are macrocyclic tetrapyrrole derivatives found widely in nature, have attracted growing interest in recent years. These lipophilic pigments exhibit remarkable chemical stability and have retained their major structural features for up to 1.1 billion years. As such, they are considered vital indicators of life and have been extensively studied, from the remnants of extinct organisms to gain insights into the principles of evolution. Porphyrins are often associated with a central metal ion within their ring system and can be modified through various substituents, including additional rings or ring opening, resulting in a wide range of functionalities. This comprehensive review summarizes recent advancements in the field of porphyrins. It begins by introducing the structures and preparation methods of porphyrins. Subsequently, it delves into notable applications of porphyrins in the context of pollutant adsorption in water and their environmentally friendly photocatalytic degradation.

Red light photocatalysis of conjugated microporous polymers based on fused thiophenes for selective oxidation of amines

By virtue of tailorable building blocks, the band gaps and electronic structures of conjugated microporous polymers (CMPs) can be readily adjusted at the molecular level. Generally, the building blocks possessing extended π-conjugations result in exceptional photocatalytic performances. In this work, the direct CH arylation of fused thiophenes, thieno[3,2-b]thiophene (TT) and dithieno[3,2-b:2',3'-d]thiophene (DTT), with 1,3,6,8-tetrabromopyrene affords two CMPs, namely TT-Py-CMP and DTT-Py-CMP. The expansion of π-conjugations of the fused thiophenes from TT to DTT gives rise to a bathochromic shift about 30 nm from TT-Py-CMP to DTT-Py-CMP. Besides, systematic characterizations suggest the optoelectronic properties of DTT-Py-CMP are better than that of TT-Py-CMP. Furthermore, DTT-Py-CMP drives better red light photocatalysis than TT-Py-CMP for the selective oxidation of amines with molecular oxygen. The selective oxidation of benzyl amines by red light photocatalysis of DTT-Py-CMP progresses via an electron transfer pathway with high selectivities for imines. This work provides new insights that fused thiophenes could be the stepping stone in designing CMPs for expansive visible light photocatalysis.

Salen-based porous aromatic frameworks with multi-active sites as anode materials for lithium-ion batteries

Porous organic polymers are considered as excellent candidates for the electrode materials in rechargeable battery due to their desirable properties including porosity, customizable structure, and intrinsic chemical stability. Herein a Salen-based porous aromatic framework (Zn/Salen-PAF) is synthesized through a metal directed method and further used as efficient anode materialfor lithium-ion battery. Attributing to the stable functional skeleton, Zn/Salen-PAF delivers a reversible capacity of 631 mAh·g^-1 at 50 mA·g^-1, a high-rate capability of 157 mAh·g^-1 at 20.0 A·g^-1 and a long-term cycling capacity of 218 mAh·g^-1 at 5.0 A·g^-1 even after 2000 cycles. Compared to the Salen-PAF without metal ions, Zn/Salen-PAF possesses better electrical conductivity and more active sites. X-ray photoelectron spectroscopy (XPS) investigation indicates that the coordination of Zn²⁺ with N₂O₂ unit not only improves the conjugation of the framework but also contributes to the in situ cross-sectional oxidation of the ligand during reaction, which results in the electron redistribution of oxygen atom and the formation of CO bonds.