Pore Size Control of Ultrathin Silicon Membranes by Rapid Thermal Carbonization

Department of Electrical and Computer Engineering, Box 270231, University of Rochester, Rochester, New York 14627, USA.
Nano Letters (Impact Factor: 13.59). 10/2010; 10(10):3904-8. DOI: 10.1021/nl101602z
Source: PubMed


Rapid thermal carbonization in a dilute acetylene (C(2)H(2)) atmosphere has been used to chemically modify and precisely tune the pore size of ultrathin porous nanocrystalline silicon (pnc-Si). The magnitude of size reduction was controlled by varying the process temperature and time. Under certain conditions, the carbon coating displayed atomic ordering indicative of graphene layer formation conformal to the pore walls. Initial experiments show that carbonized membranes follow theoretical predictions for hydraulic permeability and retain the precise separation capabilities of untreated membranes.

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