Preparation Of Functionalized Metalloporphyrin Porous Materials And Their Photoelectrochemical Catalytic Application

Porphyrins are a class of macromolecular heterocyclic compounds with unique physicochemical properties.The 26πelectrons on the porphyrin ring form a highly conjugated system,so the tetrapyrrole macroing nucleus of the porphyrin is very favorable for the complexation of metal ions.Because porphyrins have the characteristics of visible light absorption and photocatalytic energy transfer,porphyrins and their derivatives have a wide range of applications in environmental treatment,biosensing,and batteries.In particular,the unique catalytic activity of metalloporphyrin can be used as an efficient electrocatalyst,photocatalyst,biosensing material,etc.Through the molecular axial coordination of porphyrin-based material structure,the optical properties and electron transfer of porphyrin can be regulated,and the application of porphyrin in molecular recognition and metal ion sensing can be expanded.The use of metal-organic frameworks（MOFs）based on porphyrin ligands and metalloporphyrin aerogel structures to construct novel porphyrin-based porous materials can be effectively applied to photoelectrochemical catalysis with significantly enhanced performance.This paper uses porphyrin ligands as precursors to prepare functional porous materials based on metalloporphyrins,studies the structure-function relationship without affecting the structure and inherent properties of porphyrins,explores the influence of their structure on performance from a micro-macro perspective,explores its application in photoelectrochemase sensing,colorimetric sensing and photocatalytic degradation of organic dyes,and provides an experimental basis and theoretical basis for the development and application of new porphyrin-based porous materials,the main research contents are as follows:1.Hypoxantherase biosensing based on photoelectrochemical catalysis of zinc-porphyrin MOF.In this paper,a novel porphyrin MOF loaded xanthine oxidase（XOD）sensor was developed for the photoelectrochemical（PEC）detection of hypoxanthine（Hx）.The nanoscale Al-TCPP（Zn）containing zinc-porphyrin was obtained by adjusting the solvent.Then the mateial showed a significant photocurrent response under visible light irradiation,which was mainly caused by its PEC reduction of oxygen.After adding Hx,XOD catalyzes the Hx reaction to generate H₂O₂,which significantly enhances the photocurrent based on XOD/Al-TCPP（Zn）/ITO photoelectrode,which can be applied to PEC sensing of Hx.The sensor exhibits good linearity in the range of 1–100μM,and the detection limit is 0.1μM（S/N=3）.And the sensor has excellent selectivity and good reusability.This study not only enhances the understanding of the PEC properties of porphyrin MOFs,but also provides a new strategy for high-performance PEC bioanalysis based on porphyrin MOFs.2.Glucose colorimetric sensing based on Fe-porphyrin MOA-loaded glucose oxidase.Using polypropylene glycol（PPG）as gelling agent,Fe-TCPP@UiO-66-NH₂aerogels containing both mesopores and micropores were prepared,and the integration of Fe-porphyrin as peroxidase mimic into aerogels by one-pot synthesis was realized.The aerogel has a rich pore structure that can be used to encapsulate glucose oxidase（GOx）,and the prepared composite material can be used to catalyze the tandem reaction of glucose,thereby realizing colorimetric sensing of glucose.The linear range of the sensor for glucose detection is 10–400μM（R²=0.998）,and the detection limit is 0.3μM（S/N=3）.Compared with free enzymes,UiO-66-NH₂aerogel exhibits good stability under harsh conditions after encapsulation of GOx,which improves the performance of glucose colorimetric sensing,and the sensor also shows high stability and recyclability.3.Through the surface modification of functional nanomaterials,functional nanomaterials(such as noble metal NPs,Ti O₂nanospheres,carbon quantum dots（CQDs）,Ti₃C₂MXene,ketjen black（KB）and g-C₃N₄are uniformly incorporated into pure porphyrin MOF（Al-TCPP）aerogels to obtain functionalized porphyrin MOF aerogel composites.The results show that the functional nanomaterials can be uniformly dispersed in Al-TCPP aerogels through PVP,mainly due to the hydrophobic interaction between the polar groups of PVP and the solvent,and the weak coordination interaction between pyrrolidone and Al（III）ions.Furthermore,the PEC properties and photocatalytic degradation of rhodamine B by Pt@Al-TCPP and Ti O₂@Al-TCPP aerogel composites were tested.The results show that,compared with the individual Al-TCPP aerogels,composite Pt@Al-TCPP and Ti O₂@Al-TCPP aerogels exhibit enhanced PEC properties,respectively.Among them,Ti O₂@Al-TCPP aerogel composites adsorbed 73%of the initial rhodamine B within 25 min,and then basically achieved complete photocatalytic degradation of rhodamine B within 20 min.