The invention provides a method of controlling the rate of noncovalent silica deposition onto at least one carbon nanotube. The method comprises (a) providing a one chamber electrochemical cell comprising a working electrode comprising at least one carbon nanotube; a reference electrode; a counter electrode; supporting electrolytes; and a reagent solution, wherein the reagent solution comprises a precursor of silica; and (b) applying a selected negative potential to the working electrode, wherein the rate of silica deposition onto the at least one carbon nanotube increases as the potential becomes more negative.
 This invention was made with Government support from the National Science Foundation under Grant No. DMR-0348239 and U.S. Department of Energy Office of Basic Energy Sciences under contract DE-AC02-98CH 10886. The Government has certain rights in this invention.