Abnormal gas pressure sensitivity of the visible emission in ZnO quantum dots prepared by improved sol–gel method: the role of surface polarity

Abstract

Polar surface induced band bending leads to the abnormal gas pressure sensitivity of visible emission in ZnO quantum dots.

Facile Fabrication of UV Photodetectors Using Spin-Coating Flame-Synthesized ZnO Nanoparticles

“…The ZnO-2 sample exhibited significantly weaker spectra (Figure S4) when compared to thicker samples, which could be attributed to its very thin film thickness and discontinuous surface coating. For the films with over 5 spin-coating cycles, the UV emission band centered at ∼360 nm could originate from the band edge emission of the ultrasmall-sized ZnO (<10 nm) NPs (Table ), which is in line with previous reports on ZnO quantum dots (QDs) under 325 nm excitation source . The resulting PL spectrum exhibited similar features to nanostructured ZnO materials prepared through the colloidal precipitation method in ethanol .…”

“…For the films with over 5 spin-coating cycles, the UV emission band centered at ∼360 nm could originate from the band edge emission of the ultrasmall-sized ZnO (<10 nm) NPs (Table 1), which is in line with previous reports on ZnO quantum dots (QDs) under 325 nm excitation source. 53 The resulting PL spectrum exhibited similar features to nanostructured ZnO materials prepared through the colloidal precipitation method in ethanol. 54 In particular, the dominant emissions were in the UV and near-UV range, centered at approximately 393 nm, originating from the exciton recombination associated with near-band edge (NBE) emission or the free exciton emission of the nanostructured ZnO film.…”

Carbon Dioxide Precipitation Method to Prepare Zinc Oxide

“…Zinc oxide (ZnO) is one of the most valuable optical and electrical materials . ZnO nanoparticles have been synthesized using many chemical methods, such as homogeneous precipitation, calcination, sol‐gel, ionothermal precipitation method, electrochemical deposition etc. Among these chemical synthesis methods, homogeneous precipitation method is one of the most widely used method due to its low cost, scalability and reduced temperature.…”