采用水热法,以阳离子表面活性剂十六烷基三甲基溴化铵(CTAB)、非离子型表面活性剂聚乙二醇8000(PEG8000)、阴离子表面活性剂十二烷基硫酸钠(SDS)及SDS与CTAB耦合修饰Bi_2O_2CO_3。系统地研究了表面活性剂种类及用量对Bi_2O_2CO_3晶面、...采用水热法,以阳离子表面活性剂十六烷基三甲基溴化铵(CTAB)、非离子型表面活性剂聚乙二醇8000(PEG8000)、阴离子表面活性剂十二烷基硫酸钠(SDS)及SDS与CTAB耦合修饰Bi_2O_2CO_3。系统地研究了表面活性剂种类及用量对Bi_2O_2CO_3晶面、形貌、光吸收特性及光催化降解效率的影响。以紫外光下降解罗丹明B(Rh B),考察样品的光催化性能。结果表明,当Bi盐投加量为6 mmol(2.9106 g)时,SDS对Bi_2O_2CO_3的修饰对其光催化活性有所抑制;0.6 g CTAB修饰Bi_2O_2CO_3能有效提高其光催化活性;0.3 g SDS与CTAB耦合修饰Bi_2O_2CO_3就能有效提高其光催化活性;0.3 g PEG8000修饰Bi_2O_2CO_3也能使其光催化活性有所提高。展开更多
The violet polycrystalline (NH4)5[(VO)6(CO3)4(OH)9]·10H2O(NVCO) was simply sy nthesized by solution reaction using V2O5, HCl, N2H4·2HCl and NH4HCO3 as the st arting materials. The results of TGA and DTA of N...The violet polycrystalline (NH4)5[(VO)6(CO3)4(OH)9]·10H2O(NVCO) was simply sy nthesized by solution reaction using V2O5, HCl, N2H4·2HCl and NH4HCO3 as the st arting materials. The results of TGA and DTA of NVCO under H2(99.999%) atmosphe re show that V2O3 forms at 620℃. The data of TG/DTG and DTA of NVCO under N2(99 .999%) atmosphere indicate that VO2 forms at 367℃and crystallizes at 390℃. In air atmosphere, the TG/DTG and DTA of NVCO show that V2O5 forms at 354℃, cryst allizes at 366℃and melts at 664℃. The three thermolysis processes of NVCO show that a large amount of H2O, CO2 and NH3 gases fast releases during the thermoly sis of NVCO, causing that the particles of the materials split and atomize stron gly, thus to obtain V2O3, VO2 and V2O5 nano-powders finally. According to the a bove of thermoanalytical results, V2O3, VO2 and V2O5 powders were prepared respe ctively under H2, N2 and oxygen in a tube furnace. Chemical analysis and XRD exp eriments of the powders identify that pure V2O3 is obtained at 800℃for 0.5h und er H2 atmosphere; crystalline VO2 is obtained at 480℃for 0.5h in N2; amorphous VO2 is obtained at 350℃for 20min under N2 atmosphere, this has been first repor ted to prepare amorphous VO2 powder so far; pure V2O5 is obtained at 400℃for 10 min under oxygen. From the micrographs of the powders, the particle size of the V2O3, the crystalline VO2 or the V2O5 powders is 35nm, 24nm or < 40nm, respectiv ely. Above-mentioned results prove that NVCO is a good precursor for preparatio n of pure V2O3, VO2 and V2O5 nano-powders under mild conditions.展开更多
文摘采用水热法,以阳离子表面活性剂十六烷基三甲基溴化铵(CTAB)、非离子型表面活性剂聚乙二醇8000(PEG8000)、阴离子表面活性剂十二烷基硫酸钠(SDS)及SDS与CTAB耦合修饰Bi_2O_2CO_3。系统地研究了表面活性剂种类及用量对Bi_2O_2CO_3晶面、形貌、光吸收特性及光催化降解效率的影响。以紫外光下降解罗丹明B(Rh B),考察样品的光催化性能。结果表明,当Bi盐投加量为6 mmol(2.9106 g)时,SDS对Bi_2O_2CO_3的修饰对其光催化活性有所抑制;0.6 g CTAB修饰Bi_2O_2CO_3能有效提高其光催化活性;0.3 g SDS与CTAB耦合修饰Bi_2O_2CO_3就能有效提高其光催化活性;0.3 g PEG8000修饰Bi_2O_2CO_3也能使其光催化活性有所提高。
文摘The violet polycrystalline (NH4)5[(VO)6(CO3)4(OH)9]·10H2O(NVCO) was simply sy nthesized by solution reaction using V2O5, HCl, N2H4·2HCl and NH4HCO3 as the st arting materials. The results of TGA and DTA of NVCO under H2(99.999%) atmosphe re show that V2O3 forms at 620℃. The data of TG/DTG and DTA of NVCO under N2(99 .999%) atmosphere indicate that VO2 forms at 367℃and crystallizes at 390℃. In air atmosphere, the TG/DTG and DTA of NVCO show that V2O5 forms at 354℃, cryst allizes at 366℃and melts at 664℃. The three thermolysis processes of NVCO show that a large amount of H2O, CO2 and NH3 gases fast releases during the thermoly sis of NVCO, causing that the particles of the materials split and atomize stron gly, thus to obtain V2O3, VO2 and V2O5 nano-powders finally. According to the a bove of thermoanalytical results, V2O3, VO2 and V2O5 powders were prepared respe ctively under H2, N2 and oxygen in a tube furnace. Chemical analysis and XRD exp eriments of the powders identify that pure V2O3 is obtained at 800℃for 0.5h und er H2 atmosphere; crystalline VO2 is obtained at 480℃for 0.5h in N2; amorphous VO2 is obtained at 350℃for 20min under N2 atmosphere, this has been first repor ted to prepare amorphous VO2 powder so far; pure V2O5 is obtained at 400℃for 10 min under oxygen. From the micrographs of the powders, the particle size of the V2O3, the crystalline VO2 or the V2O5 powders is 35nm, 24nm or < 40nm, respectiv ely. Above-mentioned results prove that NVCO is a good precursor for preparatio n of pure V2O3, VO2 and V2O5 nano-powders under mild conditions.
