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Updated: Feb 4, 2026

Soft Lithographic Functionalization and Patterning Oxide-free Silicon and Germanium
Published on: December 16, 2011
Binding and Precipitation of Germanium(IV) by Penta- O-galloyl-β-d-glucose
Liangliang Zhang1, Yuchen Liu1, Xinyu Hu1
1Jiangsu Province Biomass Energy and Materials Laboratory , Institute of Chemical Industry of Forest Products, CAF , Nanjing 210042 , China.
Abstract:
Complex formation and precipitation of germanium by a well-characterized hydrolyzable tannin, 1,2,3,4,6-penta- O-galloyl-β-d-glucose (PGG), was studied in this work. Two simple phenolic compounds, methyl gallate and gallic acid, were also used for comparison purposes. The influence of pH on the stoichiometry and conditional association constants (log K) of the germanium complexes was investigated. UV-visible spectroscopy showed the successive formation of GePGG and Ge2PGG at pH 6.0 and of GePGG at pH 4.0. The results of the precipitation experiments indicated that germanium precipitation was influenced by organic solvents, pH values, the germanium/PGG ratio, and the presence of zinc. Acetone had the biggest effect on the solubility of these complexes, and lower pH values favored the precipitation of the complex. The results showed that a germanium/PGG ratio of more than 3:1 was essential for precipitation. Furthermore, the presence of zinc ions in the solution decreased the precipitation.
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