Porous Organic Salts:Design,Synthesis And Characterization

Porous organic materials are a new class of materials which have been widely used in various fields so far and have a very broad development prospect.As a characteristic of porous organic materials,pore has a direct influence on the properties of porous materials,thus pore is of great significance to porous organic materials.Organic salts are formed by organic acids and organic bases through non-covalent interactions.And they can achieve some specific functions owing to the non-covalent interaction.Thus,organic salts have draw much attention in recent years.However,how to introduce the pore into organic salts to prepare the porous organic salts is still a challenge.Porous Organic Salts,which are different from other crystalline or non-crystalline porous organic materials,are a new class of porous organic materials formed by non-covalent interactions.This thesis synthesizes a series of porous organic salts formed by acid and base combination,reports a detailed analysis about their structures and explores their structure-function correlation.This thesis is mainly divided into the following contents:?1?the first chapter summarizes the development of porous organic materials and organic salts in recent years,introduces the concept of porous organic salts,and gives a brief introduction about porous organic salts.?2?the second chapter chooses two organic acids of different acidities and three organic bases of varying basicities to successfully obtain four kinds of porous organic salts,namely CPOS-1,CPOS-2,CPOS-3 and CPOS-4.CPOS-1 which is synthesized from strong acid tetrakis?4-sulfophenyl?methane and strong base trans-1,4-cyclohexandiamine,exhibits excellent thermal stability,and has the highest micropore surface area of 216 m² g^-1.CPOS-2 which constructed from tetrakis?4-sulfophenyl?methane and p-phenylenediamine exhibits proton conductivity as high as 2.2 x 10^-2 S cm^-1 at 333 K and 98%RH.According to temperature-dependent proton conductivity measurements,the Ea values which calculated from Arrhenius equation are greater than 0.4 eV,which suggests four CPOSs all belong to Vehicular mechanism with water molecules as carriers to transfer protons along the channels.?3?the third chapter selects three organic acids with similar but slightly different structure and one organic base to prepare three kinds of organic salts,namely CPOS-5,CPOS-6 and CPOS-7,and explores their electronic conduction behavior.CPOS-5 has the highest electrical conductivity,while CPOS-6 is slightly lower,and CPOS-7shows no obvious electronic conduction behavior.According to the structure analysis and combined with the first principles calculation,?-?stacking is found in CPOS-5and CPOS-6 which provides electronic transmission pathway,while no such pathway found in CPOS-7.However,CPOS-7 shows the highest micropore surface area of 205m² g^-1,while CPOS-5 and CPOS-6 lose the guest molecules under vacuum which lead the crystal structure collapses.Therefore,a control of electron conduction to porosity is realized macroscopically through the small changes of monomers.?4?the fourth chapter successfully obtains six kinds of organic salts by choosing three different kinds of organic acids and three different kinds of organic bases,analysizes their structures in details and explores the role of water in their structure.The results show that water plays a double role in the lattices,?i?it acts as a struct itself and?ii?behaves as a guest in structural channels and cavities.The former is difficult to lose because of the strong binding,while the latter is easy to lose because of the weak binding.These research results are of significant value in the pharmaceutical industry.?5?the fifth chapter systematically summarizes the research work of this thesis,points out the shortcomings and prospects the future of porous organic salts.In conclusion,this thesis successfully obtains a series of porous organic salts,constructs a new system of porous materials,and explores their structure-function correlation.