Preparation of Nanoporous Materials

Abstract

A method for preparing a porous metal oxide or metalloid oxide material, the method comprising: providing an anode substrate, including a metal or metalloid substrate; providing a cathode substrate; connecting the substrates to form an electrochemical cell; applying an electrical signal to the electrochemical cell; and forming shaped pores in the metal or metalloid substrate by: (a) changing the electrical signal over time; an applied voltage of the signal to form a voltage cycle comprising a minimum voltage period in which a minimum voltage is applied, a maximum voltage period in which a maximum voltage is applied, and a transition period between said minimum voltage period and said maximum voltage period , wherein during the transition period, the voltage is rapidly increased from said minimum voltage to said maximum voltage, or (b) the current of said electrical signal is varied over time to form a current cycle comprising a period of application of a minimum current a minimum current period, a maximum current period in which a maximum current is applied, and a transition period between said minimum current period and said maximum current period, wherein during the transition period, voltage rapidly increases from said minimum current to said Maximum current.

Description

[0001] This international patent application claims priority from Australian provisional patent application 2008906329, filed 8 December 2008, the contents of which are hereby incorporated by reference. technical field [0002] The present invention generally relates to processes for making nanoporous materials, such as nanoporous alumina, and nanoporous materials formed thereby. Background technique [0003] Nanoporous materials can be described as organic or inorganic materials containing a plurality of ordered arrays of nanoscale sized pores. Typically, these pores are approximately 1 to 500 nm in diameter, and the pore density is typically 10 9 to 10 12 hole / cm 2 . Nanoporous materials have been used in a wide range of applications, such as molecular sieves, filtration, purification, template synthesis, catalysis, sensing, electronics, optics, energy storage, and drug release. [0004] Porous anodized aluminum oxide (“AAO”) prepared by an automated ordered electroche...

AI Technical Summary

Problems solved by technology

However, this method suffers from the problem that the extremely fast pulses lead to slow current recovery

Furthermore, this method only produces AAOs with simple single-tuned pore structures and cannot be used to generate pores with specific geometric shapes.

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