TY - JOUR
T1 - Aerosol Direct Writing and Thermal Tuning of Copper Nanoparticle Patterns as Surface-Enhanced Raman Scattering Sensors
AU - Aghajani, Saleh
AU - Accardo, Angelo
AU - Tichem, Marcel
PY - 2020
Y1 - 2020
N2 - Surface-enhanced Raman scattering (SERS) substrates are of great interest for detecting low-concentrated analytes. However, issues such as multistep processing, cost, and possible presence of hazardous substances in the fabrication still represent a significant drawback. In this paper, an innovative direct writing method is introduced for solvent-free and spatially selective deposition of fine metal copper nanoparticles (CuNPs), with size distribution below 20 nm, generated in-line through a spark ablation method (SAM). The deposited CuNPs' morphology and composition were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), and energy-dispersive X-ray spectroscopy (EDS). The resulting CuNP patterns feature porous 3D microdomains with nanometric structures serving as hot spots for Raman signal enhancement. Low-temperature post-treatment (below 200 °C) of the deposited CuNPs significantly evolves its morphology and leads to sintering of NPs into a semicrystalline structure with sharp geometric features, which resulted in a more than 10-fold increase of the enhancement factor (up to 2.1 × 105) compared to non-heat-treated samples. The proposed method allows creating SERS substrates constituted by sharp 3D metallic nanopatterns selectively deposited onto specific regions, which paves the way for new printed, highly sensitive SERS-based sensors.
AB - Surface-enhanced Raman scattering (SERS) substrates are of great interest for detecting low-concentrated analytes. However, issues such as multistep processing, cost, and possible presence of hazardous substances in the fabrication still represent a significant drawback. In this paper, an innovative direct writing method is introduced for solvent-free and spatially selective deposition of fine metal copper nanoparticles (CuNPs), with size distribution below 20 nm, generated in-line through a spark ablation method (SAM). The deposited CuNPs' morphology and composition were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), and energy-dispersive X-ray spectroscopy (EDS). The resulting CuNP patterns feature porous 3D microdomains with nanometric structures serving as hot spots for Raman signal enhancement. Low-temperature post-treatment (below 200 °C) of the deposited CuNPs significantly evolves its morphology and leads to sintering of NPs into a semicrystalline structure with sharp geometric features, which resulted in a more than 10-fold increase of the enhancement factor (up to 2.1 × 105) compared to non-heat-treated samples. The proposed method allows creating SERS substrates constituted by sharp 3D metallic nanopatterns selectively deposited onto specific regions, which paves the way for new printed, highly sensitive SERS-based sensors.
KW - aerosol direct writing
KW - copper nanoparticle
KW - spark ablation method (SAM)
KW - surface-enhanced Raman scattering (SERS)
KW - thermal treatment
UR - http://www.scopus.com/inward/record.url?scp=85087763154&partnerID=8YFLogxK
U2 - 10.1021/acsanm.0c00887
DO - 10.1021/acsanm.0c00887
M3 - Article
SN - 2574-0970
VL - 3
SP - 5665
EP - 5675
JO - ACS Applied Nano Materials
JF - ACS Applied Nano Materials
IS - 6
ER -