Articolo in rivista, 2021, ENG, 10.1021/acs.jpcc.1c03732

Efficient Photothermal Generation by Nanoscale Light Trapping in a Forest of Silicon Nanowires

A. Ferraro, P. Cerza, V. Mussi, L. Maiolo, A. Convertino, R. Caputo

Annalisa Convertino - Institute for Microelectronics and Microsystems, CNR, I-00133 Rome, Italy; Roberto Caputo - Physics Department, University of Calabria, I-87036 Arcavacata di Rende, CS, Italy; CNR Nanotec-Institute of Nanotechnology, I-87036 Rende, CS, Italy; Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610054, China; Antonio Ferraro - Physics Department, University of Calabria, I-87036 Arcavacata di Rende, CS, Italy; CNR Nanotec-Institute of Nanotechnology, I-87036 Rende, CS, Italy; orcid.org/0000-0003-0189-6729 Pino Cerza - Physics Department, University of Calabria, I- 87036 Arcavacata di Rende, CS, Italy; CNR Nanotec- Institute of Nanotechnology, I-87036 Rende, CS, Italy Valentina Mussi - Institute for Microelectronics and Microsystems, CNR, I-00133 Rome, Italy Luca Maiolo - Institute for Microelectronics and Microsystems, CNR, I-00133 Rome, Italy

We experimentally investigate the photothermal conversion in disordered silicon nanowires (SiNWs) grown on a glass substrate by plasma-enhanced chemical vapor deposition. The temporal and spatial response under illumination of a 532 nm laser has been measured by means of an infrared (IR) thermocamera. Fast heat generation and adjustable temperature increase from a few tens up to ?600 °C have been observed in a confined small region around the laser spot. The performing photothermal conversion is related to the efficient light trapping in SiNWs, providing enhanced absorption in the visible spectrum, and nonradiative recombination of the photogenerated carriers, typically occurring in Si. These findings combined with a lowcost, low-temperature, and large-area fabrication technology promote the disordered SiNWs as a flexible heat source well suited for applications in multiple fields including biology, precision medicine, gas detection, and nanometallurgy.

Journal of physical chemistry. C 125 , pp. 14134–14140

Keywords

silicon nanowires, photothermal effect, Light trapping

CNR authors

Caputo Roberto, Ferraro Antonio, Convertino Annalisa, Maiolo Luca, Mussi Valentina

CNR institutes

NANOTEC – Istituto di Nanotecnologia, IMM – Istituto per la microelettronica e microsistemi