Crystalline Porous Polymers For High Performance Catalyst And Electrochemical Energy Storage Materials

Crystalline porous polymers are predesigned porous polymers that possessed well-defined porosity and crystalline frameworks with abundant functionality in predicted manner.This advantage has dictated them as tailor-made functionable and prospective materials for wide range applications.The metal organic frameworks?MOFs?and the newly discovered covalent organic frameworks?COFs?compounds are typical examples of the highly crystalline and porous polymers that built under reticular chemistry guidance.Since their compositions are mainly composed by light elements,both MOFs and COFs own very low density and high surface areas,thus they are perfect candidates for gas storage and other high demand applications.Particularly,MOFs which have been researched very much earlier than COFs,have been widely employed not only as solely active materials but also as perfect precursor for generation derived-nanomaterials.Meanwhile,COFs with their profound chemical stability have been utilized in several research fields.The regular arrangement of organic building blocks in 2D or 3D COF structures generate ordered nanopore facilitating efficient ions/charges migration throughout the entire surface,thus promising for charge storage application.This doctoral thesis is created to study the potential application of MOF-derived nanomaterials,COFs and MOFs/COFs composite in the field of catalysis and electrochemical energy storage?EES?.The carbonization of MOFs transforms them into the catalytically active metal NPs@C composite.On the other hand,with bottom-up predesigned building block with specific function allows for formation of electroactive COFs with large pore and highly stable.This typical COF structure is attractive as active material for capacitor electrode.This doctoral thesis however,consist of four chapters which are consecutively arranged as follow,the brief introduction of MOFs and COFs including their potential utilization in catalysis and electrochemical energy storage is elaborated in the first chapter.In the second chapter,the hydrothermal synthesis of Co-based ZIF-67 MOF under N₂ flow is discussed along with its catalytic activity towards reduction of 4-nitophenol?4-NP?to 4-aminophenol?4-AP?.The controlled carbonization temperature lead to the formation fine Co NPs within porous N-doped carbon matrix.Remarkably,a high catalytic activity of 1.25mM/mgs with notable recyclability is shown by Co@C-N 700 sample.In the third chapter,we present a design strategy to prepare highly stable mesoporous few-layer exfoliated COFs as active materials for fabricating high rate electrochemical double layer capacitor?EDLC?electrodes.The obtained new mesoporous JUC-COFs?JUC-510,JUC-511 and JUC-512?series possess high surface areas and mesoporous open channels with remarkable chemical and thermal stabilities.Milder chemical exfoliation over JUC COFs,produces exfoliated-COFs?e-JUC-510 e-JUC-511,and e-JUC-512?with average thickness of²2 nm and they exhibit preservation of structural order.Notably,the EDLC electrodes-based e-COFs demonstrate DL charge storage at high charge-discharge rate(up to 30,000 mV s^-1),high areal capacitance(5.46 mF cm^-2 at 1,000 mVs^-1),low?₀ value?121 ms?,and high gravimetric power(55 kW kg^-1),which are superior to graphitic-carbon microcapacitors and conventional capacitors.In addition,they also maintain almost100%capacitance stability even after 10,000 cycles.In the last chapter,we realize MOF@COF composite?MOF@TpPa-COF?as promising dual acid-base catalyst for catalyzing tandem conversion of benzaldehyde into cyanohydrin.The MOF@TpPa-COF composite catalyst exhibit controlled,quicker and higher tandem conversion from initial reactant to the final product,while the MOF counterpart shown uncontrolled,slower and lower conversion.The results further confirm that the spatial arrangement of active sites in MOF/COF composite catalyst could lead the effective catalytic activity towards tandem reaction.In conclusion,MOFs and COFs are prospective crystalline porous polymers with tailored functionalities and high chemical and thermal stabilities.The predesignable structural compositions and functionality in MOFs and COFs made them promising in catalysis and EES applications.The works provided in this doctoral thesis aim to show how MOFs and COFs are designed and employed as catalyst and capacitor electrode with outstanding performance,outperforming of other porous materials analog.