An open-framework silicoaluminophosphate(SAPO)material with a composition of Cs_(2)(Al_(0.875)Si_(0.125))4(P_(0.875)Si_(0.125)O_(4))_(4)(HPO_(4))was synthesized in an organic template-free cesium-containing system und...An open-framework silicoaluminophosphate(SAPO)material with a composition of Cs_(2)(Al_(0.875)Si_(0.125))4(P_(0.875)Si_(0.125)O_(4))_(4)(HPO_(4))was synthesized in an organic template-free cesium-containing system under hydrothermal conditions.The material was resolved to be isostructural with an open-framework aluminophosphate(AlPO)material AlPO-CJ19,which was previously synthesized using pyridine as the solvent and 2-aminopyridine as the organic template via a solvothermal route.The substitution of organic templates by alkaline cations not only makes the current synthesis protocol more favorable from an environmental point of view but also leads to a significantly improved thermal stability of this structure.The framework remained completely stable at a temperature of 510℃.A high-temperature polymorph was discerned at a temperature higher than 540℃,the structure of which is revealed to crystallize in the P1c1 space group.UV-vis results reveal that cobalt and copper cations could be readily incorporated through simple ion-exchange treatment.The conductivity of the material is 1.70×10^(-4) S cm^(-1)(293 K,30%relative humidity)as revealed by the alternating current(A.C.)impedance spectroscopy analysis.This is the first report of the synthesis of a silicon-containing phase with an AlPO-CJ19 structure.展开更多
基金support from the Sino-French joint laboratory“Zeolites”.
文摘An open-framework silicoaluminophosphate(SAPO)material with a composition of Cs_(2)(Al_(0.875)Si_(0.125))4(P_(0.875)Si_(0.125)O_(4))_(4)(HPO_(4))was synthesized in an organic template-free cesium-containing system under hydrothermal conditions.The material was resolved to be isostructural with an open-framework aluminophosphate(AlPO)material AlPO-CJ19,which was previously synthesized using pyridine as the solvent and 2-aminopyridine as the organic template via a solvothermal route.The substitution of organic templates by alkaline cations not only makes the current synthesis protocol more favorable from an environmental point of view but also leads to a significantly improved thermal stability of this structure.The framework remained completely stable at a temperature of 510℃.A high-temperature polymorph was discerned at a temperature higher than 540℃,the structure of which is revealed to crystallize in the P1c1 space group.UV-vis results reveal that cobalt and copper cations could be readily incorporated through simple ion-exchange treatment.The conductivity of the material is 1.70×10^(-4) S cm^(-1)(293 K,30%relative humidity)as revealed by the alternating current(A.C.)impedance spectroscopy analysis.This is the first report of the synthesis of a silicon-containing phase with an AlPO-CJ19 structure.
