PREPARATION, CHARACTERIZATION, AND IONIC-CONDUCTIVITY OF NOVEL CRYSTALLINE, MICROPOROUS GERMANATES, M3HGE7O16.XH2O, M = NH4+, LI+, K+, RB+, CS+ X = 4-6 .2.

被引：40

作者：

FENG, SH ^{[1
]}

GREENBLATT, M ^{[1
]}

机构：

[1] RUTGERS STATE UNIV,DEPT CHEM,PISCATAWAY,NJ 08855

来源：

CHEMISTRY OF MATERIALS | 1992年 / 4卷 / 02期

关键词：

D O I：

10.1021/cm00020a041

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

A series of crystalline, microporous germanates, M3HGe7O16.xH2O, M = NH4+, Li+, x = 6; M = K+, Rb+, Cs+, x = 4, were synthesized hydrothermally and characterized by powder X-ray diffraction, differential thermal analysis, and thermogravimetric analysis. Ionic conductivity in both hydrated and dehydrated samples was investigated by ac impedance in the temperature range 25-550-degrees-C. The protonic conductivity is highest in (NH4)3HGe7O16.6H2O, 3.1 x 10(-4) (OMEGA-cm)-1 at 144-degrees-C. The best ionic conductivity was found in Cs3HGe7O16, 2.0 x 10(-3) (OMEGA-cm)-1 at 400-degrees-C. The ionic conductivity of dehydrated M3HGe7O16 increases and the activation energy decreases with increasing cation radius from room temperature to 500-degrees-C. This behavior is consistent with a reduced Coulombic attraction between the mixed tetrahedral-octahedral (GeO4-GeO6) anion framework structure of the germanates and the cations located in their channels, compared with that in other zeolite-type compounds.

引用

页码：462 / 468

页数：7

共 25 条

[1]

ANDERSEN EK, 1986, SOLID STATE IONICS, V18-9, P1170

[2] PROTONIC CONDUCTIVITY IN HYDRATES [J].

BARBOUX, P ;

MORINEAU, R ;

LIVAGE, J .

SOLID STATE IONICS, 1988, 27 (04) :221-225

[3]

Barrer R. M., 1982, HYDROTHERMAL CHEM ZE

[4] NMR STUDIES ON ZEOLITIC HEPTAGERMANATES [J].

BITTNER, H ;

KERBER, W .

MONATSHEFTE FUR CHEMIE, 1969, 100 (02) :427-&

[5]

BRECK DW, 1974, ZEOLITE MOL SIEVES, P457

[6] STRUCTURE AND COMPOSITION OF MINERAL PHARMACOSIDERITE [J].

BUERGER, MJ ;

DOLLASE, WA ;

GARAYCOC.I .

ZEITSCHRIFT FUR KRISTALLOGRAPHIE KRISTALLGEOMETRIE KRISTALLPHYSIK KRISTALLCHEMIE, 1967, 125 (1-6) :92-&

[7]

CORCORAN EW, 1989, ZEOLITE SYNTHESIS, P603

[8]

FENG S, IN PRESS CHEM MATER

[9]

FENG S, 1988, CHEM J CHINESE U, V4, P9

[10]

Flanigen E., 1976, ZEOLITE CHEM CATALYS

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