Nanocharacterization Studies on Surface Modified Nanoporous Gold Films for Sensor Applications

M. Joshi, S. Swastic, J.K. Vemula, K. Priydarshi, A. Deshpande, S.R. Ramanan, J.N. Krishnan
BITS Pilani K K Birla Goa Campus,

Keywords: nanocharacterization, NPGF, AFM, STM, L-Cysteine


Nano porous gold film is fabricated by electroless plating with Potassium Gold Cyanide as plating solution. E-beam deposited Cu substrates are chosen for plating experiments. SEM studies revealed the pore size to be 100+20 nm for the nanoporous gold film prepared using electroless plating. The nanoporous gold film is surface modified with L-Cysteine SAM for copper detection. Both the bare and surface modified nano porous gold film is investigated through AFM and STM. AFM studies revealed that the increase in adsorption time from 30 min to 24 h decreased the surface roughness by ~90%. The STM results proved the increase in surface coverage of the L-cysteine SAM on nanoporous gold film paving way for an effective gateway to build nanosensors for heavy metal ion detection.