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Hexagonal nanoporous germanium through surfactant-driven self-assembly of Zintl clusters

Authors: Dong Sun, Andrew E. Riley, Ashley Cadby, Erik K. Richman, Scott D. Korlann, Sarah H. Tolbert

Date: September 2015

Type: Journal article, Nature, 441(7097)

Download a PDF version of the paper from Nature


Surfactant templating is a method that has successfully been used to produce nanoporous inorganic structures from a wide range of oxide-based material.

Co-assembly of inorganic precursor molecules with amphiphilic organic molecules is followed first by inorganic condensation to produce rigid amorphous frameworks and then, by template removal, to produce mesoporous solids.

A range of periodic surfactant/semiconductor and surfactant/metal composites have also been produced by similar methods but for virtually all the non-oxide semiconducting phases, the surfactant unfortunately cannot be removed to generate porous materials.

Here we show that it is possible to use surfactant-driven self-organisation of soluble Zintl clusters to produce periodic, nanoporous versions of classic semiconductors such as amorphous Ge or Ge/Si alloys. Specifically, we use derivatives of the anionic Ge94- cluster, a compound whose use in the synthesis of nanoscale materials is established. Moreover, because of the small size, high surface area, and flexible chemistry of these materials, we can tune optical properties in these nanoporous semiconductors through quantum confinement by adsorption of surface species, or by altering the elemental composition of the inorganic framework.

Because the semiconductor surface is exposed and accessible in these materials, they have the potential to interact with a range of species in ways that could eventually lead to new types of sensors or other novel nanostructured devices.

Citation information


Abstract = {`Porous'silicon was hailed as an exciting new material for microelectronics when it was first produced 15 years ago. It provided an alternative range of properties to complement those of crystalline silicon. Now germanium, another element important in microelectronics, has come under scrutiny, and two groups report the use of a technique called surfactant templating to synthesize germanium with ordered pores: one group obtains cubic, and the other, hexagonal geometry. Initial investigations show that, as with porous silicon, these materials also have differing properties to their bulk counterparts.},

Author = {Sun, Dong and Riley, Andrew E. and Cadby, Ashley J. and Richman, Erik K. and Korlann, Scott D. and Tolbert, Sarah H.},

Da = {2006/06/01},

Date-Added = {2019-08-21 22:25:27 +0000},

Date-Modified = {2019-08-21 22:25:27 +0000},

Doi = {10.1038/nature04891},

Id = {Sun2006},

Isbn = {1476-4687},

Journal = {Nature},

Number = {7097},

Pages = {1126--1130},

Title = {Hexagonal nanoporous germanium through surfactant-driven self-assembly of Zintl clusters},

Ty = {JOUR},

Url = {},

Volume = {441},

Year = {2006},

Bdsk-Url-1 = {}}

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Author: Ashley Cadby

Date: April 2019

Type: Preprint

Read the paper online


Existing optical microscopy techniques compromise between resolution, photodamage, speed of acquisition and imaging in to deep samples. This often confines a technique to a certain biological system or process.

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