Combination of capture and simultaneous conversion of CO₂ into valuable chemicals is a fascinating strategy for reducing CO₂ emissions. Therefore, searching for heterogeneous catalysts for efficient catalytic conversion of CO₂ is of great importance for carbon capture and utilization. Herein, we report a metalloporphyrin-based covalent organic framework (Co(II)@TA-TF COF) that can capture CO₂ and simultaneously convert it into cyclic carbonates under mild conditions. The COF was designed to possess micropores for the adsorption of CO₂ and integrated with cobalt(II) porphyrin (Co(II)@TAPP) units as catalytic sites into the vertices of the layered tetragonal networks. The structure of the Co(II)@TA-TF COF is unique where Co(II)@TAPP units are alternately stacked along the z direction with a slipped distance of 1.7 Å, which gives an accessible space to accommodate small molecules, making it possible to expose catalytic sites to substrates within the adjacent stacked layers. As a result, this COF is found to be highly effective for the addition of CO₂ and epoxides. Importantly, the Co(II)@TA-TF COF exhibited a dramatic size selectivity for substrates. In conjunction with its reusability, our results highlight the development of a new function of COFs for targeting simultaneous CO₂ absorption and utilization upon complementary exploration of the structural features of skeletons and pores. Such promising catalytic performance of the COF makes it possible for its potential practical application.

Graphitic anode materials are commonly used in commercial lithium-ion batteries (LIBs), where the energy density potential has been fully exploited to about ∼360 mA h g⁻¹ (372 mA h g⁻¹ for LiC₆), and it is hard to make further significant improvement. Owing to their highest theoretical specific capacity (4200 mA h g⁻¹ for Li_4.4Si), abundant earth reserves and environment-friendly silicon anode materials have great potential to be installed in next-generation high-energy-density LIBs. However, the industrialization of silicon-based anodes is hampered by the considerable volume change (∼300–400%) upon the lithiation/de-lithiation process, which inevitably causes particles’ pulverization, electrode cracking/swelling, and parasitic side reactions and leads to electric contact loss and eventual electrode destruction. Therefore, binders in silicon-based electrode systems adhere to active material particles and conducting additives, and tie up the matrix laminate and the current collector, which play a focal role in cell performances. Accordingly, the essential requirement of binders for Si-based anodes is briefly introduced; the binder's mechanical properties in terms of the tensile properties, adhesion strength of binders with Si particles and the peel strength of the electrode are emphasized. Moreover, the electronic conductivity and ionic conductivity of binders are proposed to improve the electrochemical performance of Si-based electrodes. Likewise, the mechanical degradation of the Si electrodes and their robust binder strategies will also be discussed. Finally, viable strategies are discussed to address the challenge of binders as the future development direction and application prospects.