Structural and photoluminescence properties of tin oxide and tin oxide: C core–shell and alloy nanoparticles synthesised using gas phase technique

Abstract

In the present study, we report a controlled growth of tin oxide and tin oxide: carbon nanoparticles by an integrated method comprising of the gas phase agglomeration, electrical mobility based size selection, and in–flight sintering steps. The effect of in-flight sintering temperature and variation in growth environment (N2, H2 and O2) during nanoparticle formation, morphology and composition has been investigated by carrying out High Resolution Transmission Electron microscopy and X-Ray diffraction studies. The results highlight the novelty of the present technique to grow alloy and core-shell nanoparticles in which the stoichiometery (x) of SnOx and the mode of incorporation of carbon into the tin oxide lattice (alloy or core-shell structure), along with well-defined size can be controlled independently. Detailed Photoluminescence (PL) studies of well sintered monocrystalline SnO, SnOx and SnO2 nanoparticles along with SnOx:C and SnO2:C alloy and C@SnO core-shell nanoparticle has been carried out. The shift in the position and nature of PL peaks due to band edge, Sn interstitials and oxygen vacancy defect level energy states has been understood as a function of stoichiometery and nanoparticle structure (alloy and core-shell). These results suggest the possibility of tailoring the position of these levels by controlling the size, composition and alloying which is potentially important for gas sensing, photoconductivity and photo-electrochemical applications.

Improved hole injection for blue phosphorescent organic light-emitting diodes using solution deposited tin oxide nano-particles decorated ITO anodes

“…Figure 1(d) shows that the NPs tend to be a polycrystalline agglomerate of smaller particles with amorphous regions that could be C, or amorphous Sn oxides. Carbon is known to stabilize NPs and alloying with C has been an effective method of tuning the electronic properties of SnO x NPs 32 . Given our use of diblock co-polymer micelles for the formation of the NPs, it is likely that some carbon has been incorporated into the SnO x matrix.…”

“…Second, low temperature growth of tin oxides often results in mixed phases, with SnO 2 and SnO coexisting as a result of the metastable nature of SnO 30,31 . Mixed phase alloying has been an effective method of tuning the electronic properties of SnO x NPs 32 . Finally, the surface of ITO is known to be tin-rich, with SnO 2 -like crystalline domains 33–35 .…”

Nontoxic photoluminescent tin oxide nanoparticles for cell imaging: deep eutectic solvent mediated synthesis, tuning and mechanism

“…45 This type of emission which is not exactly "band gap emission" but having a lower energy than BG is known as "near band edge emission" and is already reported by several other researchers. [48][49][50][51] Mostly the visible light emission is known to be related to the defects arising from oxygen vacancies and Sn interstitials. The SnO 2 host matrix as in case of other metal oxides consists of oxygen vacancies which are created due to the escape of O 2ions from the lattice.…”

UV‐visible absorption and photoluminescence characteristics of SnO2 nano‐tube/wire arrays fabricated by LPD method

“…It is found that the PL spectra exhibit a strong UV‐visible light emission centered at 364 nm and a blue light emission band centered at 438 nm for SnO 2 nanowire arrays, as well as a faint blue light emission centered at 436 nm for pinecone‐like SnO 2 nanoparticles, which is in agreement with the effective band gap values. However, the luminescence in SnO 2 is generally believed to originate mainly from the energy states introduced in the band gap due to defects such as tin interstitials, oxygen vacancies, or dangling bonds . The performance and properties of a material primarily depends on the efficiency and precise nature of synthesis and fabrication methods.…”

“…However, the luminescence in SnO 2 is generally believed to originate mainly from the energy states introduced in the band gap due to defects such as tin interstitials, oxygen vacancies, or dangling bonds. 31 The performance and properties of a material primarily depends on the efficiency and precise nature of synthesis and fabrication methods. When developing a new synthesis and fabrication method for generating 1D nanostructures, the most important issue that one needs to address is the simultaneous control over dimensions, morphology, phase purity, and chemical composition.…”