Low temperature and cost-effective growth of vertically aligned carbon nanofibers using spin-coated polymer-stabilized palladium nanocatalysts

One-dimen­sion­al car­bon nano­struc­tures have been known and fab­ric­ated for more than a hun­dred years and were ori­gin­ally rWe describe a fast and cost-effect­ive pro­cess for the growth of car­bon nan­ofibers (CNFs) at a tem­per­at­ure com­pat­ible with com­ple­ment­ary met­al oxide semi­con­duct­or tech­no­logy, using highly stable polymer–Pd nan­o­hybrid col­loid­al solu­tions of pal­la­di­um cata­lyst nan­o­particles (NPs). Two polymer–Pd nan­o­hybrids, namely poly(lauryl methacrylate)-block-poly(2‑acetoacetoxy)ethyl methacrylate)/Pd (Lau­MAx-b-AEMAy/Pd) and polyvinylpyrrolidone/​Pd were pre­pared in organ­ic solvents and spin-coated onto sil­ic­on sub­strates. Sub­sequently, ver­tic­ally aligned CNFs were grown on these NPs by plasma enhanced chem­ic­al vapor depos­ition at dif­fer­ent tem­per­at­ures. The elec­tric­al prop­er­ties of the grown CNFs were eval­u­ated using an elec­tro­chem­ic­al meth­od, com­monly used for the char­ac­ter­iz­a­tion of super­ca­pa­cit­ors. The res­ults show that the polymer–Pd nan­o­hybrid solu­tions offer the optim­um size range of pal­la­di­um cata­lyst NPs enabling the growth of CNFs at tem­per­at­ures as low as 350 °C. Fur­ther­more, the CNFs grown at such a low tem­per­at­ure are ver­tic­ally aligned sim­il­ar to the CNFs grown at 550 °C. Finally the capa­cit­ive beha­vi­or of these CNFs was sim­il­ar to that of the CNFs grown at high tem­per­at­ure assur­ing the same elec­tric­al prop­er­ties thus enabling their usage in dif­fer­ent applic­a­tions such as on-chip capa­cit­ors, inter­con­nects, thermal heat sink and energy stor­age solutions.