Construction And Light-driving Hydrogen Evolution Of [FeFe]-Hydrogenase Model Porphyrin-containing Covalent Organic Frameworks

Covalent Organic Frameworks（COFs）constructed with porphyrin-containing amino,aldehyde and other functional groups,have various features,such as higher specific surface area,good crystallinity,excellent thermal stability,configurable pore size and easy to functionalize and modify.These materials have been found applications in gas selective adsorption and separation,energy storage and conversion,catalysis,especially associated with catalysis of light absorption of porphyrin.At present,most porphyrin-containing COFs require precious metals as cocatalysts to participate in the reaction of photocatalytic hydrogen production.The high price and scarcity of precious metals have largely restricted the development of photocatalytic hydrogen production.Iron-Iron Hydrogenase has high photocatalytic activity of hydrogen production,but the structure and activity suffer from heating or oxygen.Interestingly,embedding Iron-Iron Hydrogenase model into COFs can effectively improve the stability of Iron-Iron Hydrogenase model.On the basis of summarizing the photocatalytic hydrogen production of COFs,Iron-Iron Hydrogenase model-porphyrin-containing covalent organic frame materials,connected by the covalent or coordination bonds,have been designed,and the activity of photocatalytic hydrogen production were investigated.This thesis mainly includes the following aspects:（1）summarizing the latest research progresses of porphyrin-containing COFs and Iron-Iron Hydrogenase model achieved in the photocatalysis of hydrogen production,put forward the design idea of this paper.（2）5,10,15,20-tetra（4-aminophenyl）porphyrin（TAPP）,2,5-dipargynoxy1,4-benzaldehyde（BPTA）,azido-functionalized Iron-Iron hydrogenase model（N₃C₆H₄adt）were synthesized.Different contents of three-bond porphyrin-containing COFs,TA-DHPA-X-BPTA（X=25%,50%,100%）were synthesized by the different molar ratios of BPTA vs DHPA with TAPP;TA-DHPA-X-BPTA-N₃C₆H₄adt（X=25%,50%,100%）were synthesized by Click reaction between the azide group of N₃C₆H₄adt and the alkynyl group of TA-DHPA-X-BPTA.The structures,constitute and microtopography of TA-DHPA-X-BPTA and TA-DHPA-X-BPTA-N₃C₆H₄adt were characterized by FTIR,XRD,BET,TG,ICP,SEM,TEM and XPS,and the activity of photocatalytic hydrogen production was investigated by gas chromatography under continuous visible light irradiation using TA-DHPA-X-BPTA,TA-DHPA-X-BPTA-N₃C₆H₄adt as composite photocatalyst.（3）COF-366-Zn-NC₅H₄CH₂adt,TA-X-Zn TA-NC₅H₄CH₂adt-BDA linked by coordination bonds were constructed in two different ways.（1）COF-366 was synthesized by TAPP and p-benzaldehyde（BDA）using solvothermal method;COF-366-Zn was achieved by the reaction of COF-366 with Zn（Ac）₂;（2）Zn-TAPP was synthesized by TAPP with Zn（Ac）₂;TA-X-Zn TA-BDA（X=25%,50%,100%）were yielded by heating the different molar ratios of Zn-TAPP vs TAPP with BDA in solution.COF-366-Zn-NC₅H₄CH₂adt or TA-X-Zn TA-NC₅H₄CH₂adt-BDA was obtained by soaking COF-366-Zn or TA-X-Zn TA-BDA in solution containing NC₅H₄CH₂adt at room temperature.The structure,constitute and microtopography of COF-366-Zn-NC₅H₄CH₂adt,TA-X-Zn TA-NC₅H₄CH₂adt-BDA were characterized by FTIR,XRD,BET,TG,ICP,SEM,TEM and XPS,ICP.The activity of photocatalytic hydrogen production was investigated by gas chromatography under continuous visible light irradiation using COF-366-Zn,COF-366-Zn-NC₅H₄CH₂adt,TA-X-Zn TA-BDA,TA-X-Zn TA-NC₅H₄CH₂adt-BDA as photocatalyst.