The photophysics of porous silicon: technological and biomedical implications

Abstract

Although porous silicon (pSi) was first obtained in the mid-20th century, considerable interest in this material arose much later, due to the discovery of its room-temperature photoluminescence (PL). In the 1990s, most studies on pSi were focused on the analysis and explanation of its photoluminescent and electroluminescent characteristics and their potential practical applications. The latest advances in pSi research are related to its biocompatibility and biomedical applications. The discovery of singlet oxygen generation by pSi through nonradiative transfer of photoexcitation energy has opened new prospects for photodynamic therapy in vivo, and the discovery of laser desorption/ionization on pSi has paved the way for advanced approaches in mass-spectrometry. In this study, the main photophysical properties of pSi are reviewed, and a wide range of photo-processes characteristic of pSi and their practical implications are analyzed in terms of the general principles of energy and charge transfer. Special attention is paid to the possible applications of pSi and pSi-based nanocomposites in photonics, biophysics, medicine, and analytical chemistry.

Porous Silicon Photonic Crystal as a Substrate for High Efficiency Biosensing

“…surface of the photonic crystal should be able to interact with the analyte in order to use it for sensing. Photonic crystals made of porous structures thus could be effectively applied in biosensor field [3], [7], [8].…”

“…One of the most interesting materials for fabrication of porous photonic crystals is porous silicon [8] (pSi). Ability to precisely control the fabrication process allows one to obtain highly ordered multi-layer structures and to construct one-dimensional photonic crystals such as distributed Bragg reflectors, Rugate-filters and microcavities [9]- [11].…”

Luminescence from micro-/nano-scale anodic aluminum oxide containing electrochemical etching derived nanoporous silicon

“…Development of environmental friendly materials with strong and stable luminescence as well as good biocompatibility is particular important for designed functional materials in the field of modern optoelectronic applications such as white light emission diode (white LED) and nanomedicine [1][2][3]. Fundamentally, the most common way to generate white LED is relied on utilizing Red/Green/Blue (RGB) tri-color materials [4,5].…”

Modeling and Optimization of the Porous Silicon Photonic Structures

“…Porous silicon (pSi) is a widely used material for fabrication of porous structures, which could be used in different devices including gas sensors and biosensors [1]- [3]. Ability to precisely control the porosity and hence the refractive index during the formation makes porous silicon suitable to obtain various multilayer porous structures including one-dimensional photonic crystals [4], [5].…”