Study On Al(Ga)/P/Ge System By Hydrothermal And Solvothermal Synthesis Methods

Inorganic microporous materials have popular application in catalysis,adsorption, ion-exchange, separation and host-guest assemblies due to their uniquepore architectures. And the rational design and synthesis of new microporouscompounds, as well as the development of new synthetic ways are becoming thetopics of microporous chemistry. In the last decade, the synthesis of new materialsthat might combine the nanoporosity of zeolites with the magnetic and opticalproperties, electronic conductivity and ferrodlectricity of transition metal phosphatessuch as TiPOs, VPOs, FePOs, ZnPOs and CoPOs have been reported in the literature.Many of these materials exhibit unique structures and may have potentialapplications in catalysis and magnetic field. In addition to phosphates, openframework metal arsenates, phosphite, selenite, germanates, sulfates and carbonatehave also been reported in the literature. The successful syntheses of these newcompounds with open-framework open a new field for the microporouscompounds.Germanates have received considerable attention.In contrast tosilicon,which is usually in a tetrahedral invironment of oxygen atoms,germanium iscoordinated by four,five,or even six oxygen atoms.Maybe it can form many differentstructures.In order to synthesize more and more new phosphate compounds which exhibitgreat varieties in structure and composition,we do research in aluminophosphates andgallophosphates compounds on the one hand,and study Al(Ga)/P/Ge system on theother hand.Recently, a number of aluminophosphate compounds with 1-D chain, 2-D layerand 3-D open-framework have been developed hydrothermally or solvothermally.These compounds exhibit great varieties in structure and composition.A 3-D open framework aluminophosphate AlPO-CJ2 was synthesizedhydrothermally from reaction mixtures containing Aluminum iso-propoxide(Al(i-Pro)3,A.R.) , orthophosphoric acid ( 85 % H3PO4, G.R. ), Trimethylamine(TMA,33 % .),and ammonium fluoride,in a molar ratio of 1.0Al2O3:0.9P2O5:4.4NH4F:26.5TMA.The mixtures were heated at 453K for seven days.In thisreaction system ,we used TMA in stead of hexamehtylenetetramine(HMTA.) andpure water.We can also get AlPO-CJ2 in the molar ratios of(0.8~1.0)Al2O3:0.9P2O5:(3.5~4.4)NH4F: (26.5~35.2)TMA.TMA can be replaced bydimethylame(33%),methylame(33%)and ammonia(25%).A 3-D open framework aluminophosphate JDF-2 was synthesizedhydrothermally from reaction mixtures containing Aluminum iso-propoxide(Al(i-Pro)3,A.R.),orthophosphoric acid(85%H3PO4, G.R.),Sodium hydroxide andpure water, in a molar ratio of 1.0Al2O3:1.2P2O5: 2.15 NaOH:163H2O. The mixtureswere heated at 453K for six days. In this reaction system ,we used Na+ and H2O instead of methylamine as templates to form the JDF-2 stucture.A 3-D open framework aluminophosphate AlPO-15 was synthesizedhydrothermally from reaction mixtures containing Aluminum iso-propoxide(Al(i-Pro)3,A.R.) , orthophosphoric acid ( 85 % H3PO4, G.R. ), Trimethylamine(TMA,30%.),and ammonium fluoride,in a molar ratio of 1.0Al2O3:0.9P2O5: 6.6TMA: 0.27NH4F, The mixtures were heated at 453K for seven days.When Al/P=10/1~1/1 and the PH value is 7~9,we use dimethylame(33%),methylame(33%),ammoni(a25%)or Sodium hydroxide solution instead of TMA,and also get AlPO-15products.As the hydrothermal and solvothermal synthesis been developed, Recently, wehave got a number of gallophosphate compounds with 1-D chain, 2-D layer and 3-Dopen-framework.We have got a 3-D gallophosphate using the mixture with a molar ratio of1Ga2O3: 7.4H3PO4:9.2DAB:80EG:156H2O:0.078,when slightly change the ratio,wehave got two other gallophosphate templated by 1,4-diaminobutane(GaPO-DAB-1Dand GaPO-DAB-3D)To get a 3-D gallophosphate named GaPO-TETA ,A mixture with a molar ratioof 1Ga2O3: 5.18H3PO4:2.68TETA:1110H2O was heated at 453K for two days.thestructure is similar to the one synthesized in 2000 which was templated by1,3-diaminopropane.A 2-D layered gallophosphate named GaPO-DACH was synthesized from amixture with a molar ratio of 1Ga2O3: 4.6H3PO4:4.37DACH:67EG:140H2O.themixture was heated at 433K for five days.The layers stack in AB pattern.The organicmolecules in the mixture not only acts as a space-filler, structure director and chargebalancer, but also act as a ligand coordinating to two octahedral Al atoms.According to the synthesis conditions of some 1-D,2-D,3-D alumino-phosphates , gallophosphates and silicoaluminophosphates,we try to implantgermanium into aluminophosphate or gallophosphate framework.But finally wefailed to get the ideal product.This maybe because of the PH value,maybe due tosome other unknown reasons.We will try our best to synthesize new chemical species in the future,since it isthe most important thing.