Abstract
Silicon nanoparticles (Si NPs) with a diameter size ranging from 4 to 8 nm were successfully fabricated. They exhibit a visible photoluminescence (PL) due to the quantum confinement effect. Chemical functionalization of these Si NPs with alkyl groups allowed to homogeneously disperse them in nonpolar liquids (NPLs). In comparison to most of literature results for Si NPs, an important PL peak position variation with temperature (almost 1 meV/K) was obtained from 303 to 390 K. The influence of the liquid viscosity on the peak positions is also presented. These variations are discussed considering energy transfer between nanoparticles. The high PL thermal sensitivity of the alkyl-capped Si NPs paves the way for their future application as nanothermometers.
Highlights
Silicon nanoparticles (Si NPs) or ‘quantum dots’ (QDs) are widely investigated by the scientific community because of their interesting optical and electronic properties which differ from those of the bulk Si and, their potential use in several applications ranging from nanoelectronic to optoelectronic and photovoltaic devices or biological imaging [1,2,3]
Si NPs in colloidal form exhibit visible photoluminescence (PL) with a high quantum yield because of the confinement effect which partly overcomes the indirect band gap and which can be tuned by the NP size [4,5,6]
Their diameter is mainly ranging from 4 to 8 nm with the presence of few smaller and larger NPs. This size distribution has been confirmed on functionalized Si NPs dispersed in squalane by dynamic light scattering (DLS) measurement (Figure 1B)
Summary
Silicon nanoparticles (Si NPs) or ‘quantum dots’ (QDs) are widely investigated by the scientific community because of their interesting optical and electronic properties which differ from those of the bulk Si and, their potential use in several applications ranging from nanoelectronic to optoelectronic and photovoltaic devices or biological imaging [1,2,3]. H-terminated Si QDs have spectrally tunable PL and low radiative rates and are chemically unstable and oxidable [7,8] Dedicated surface engineering such as alkyl chains by organic capping involving a carbon surface termination has led recently to bright luminescent Si NPs [9,10,11,12,13]. These NPs have stable surface passivation due to the strong covalent Si-C bond preventing photooxidation and aggregation in solution [14]. They are nontoxic [16] and show bright photo-stable blue-green PL with fast decay for 2- to 3-nm size [17,18]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
