Effects of deposition parameters on structures and photoluminescence of MoO3- nanomaterials grown by CVD

Two-Dimensional Lateral Heterostructures Made by Selective Reaction on a Patterned Monolayer MoS2 Matrix

“…At 700 °C, both E 2g and A 1g Raman modes of MoS 2 in the unoxidized region remain virtually unchanged after selenization, while the E 2g (289.5 cm –1 ) and A 1g (242.3 cm –1 ) modes of monolayer MoSe 2 ,, in the oxidized region appear, indicating that the selective selenization occurs at this temperature. This growth temperature is much lower than the temperatures reported in previous work (usually over 800 °C), ,,− which can be attributed to the existence of the ultrathin and defect-rich MoO x generated by laser oxidization of monolayer MoS 2 . According to the literature, a high temperature is more conducive to grow a vertical heterojunction under normal circumstances.…”

“…13 Figure 1d−f shows the corresponding optical microscopy images of the formation process for a MoSe 2 /MoS 2 heterostructure. The weak contrast of LS-MoS 2 in Figure 1e indicates the existence of MoO x because its band gap exceeds the range of visible light, 33 while the contrast becomes deeper after the selenization process (Figure 1f), suggesting that the LS region is successfully selenized. 34 Raman spectroscopy was used to characterize the composition of the heterostructure.…”

“…To further investigate the mechanism for the formation of the lateral heterostructure, we studied the oxidization process under different conditions. As the Raman peaks of MoO x are usually hard to be detected for its trace amount, 33 we use the reduction in the intensity of MoS 2 Raman peaks as the fingerprint to derive the oxidation degree after the laser writing. Figure 4a shows that with the increase of laser intensity, MoS 2 Raman peaks gradually diminish and finally almost disappear, suggesting the gradual increase of oxidation degree and the ultimate full oxidation.…”

Bringing Earth-Abundant Plasmonic Catalysis to Light: Gram-Scale Mechanochemical Synthesis and Tuning of Activity by Dual Excitation of Antenna and Reactor Sites

“…The PL spectra for both samples displayed PL emission peaks in the 400–620 nm region. The peak around 425 nm was attributed to the radiative recombination of interband excitons in crystalline MoO 3 , which can be shifted as a function of the size and shape of the nanomaterials. , The presence of multiple lower energy bands can be assigned to defect emission, mainly due to oxygen vacancies, and the intervalence charge transfer transitions. − Finally, there was a decrease in the PL intensity for the Au/MoO 3 _P sample as compared to MoO 3 _P, indicating that the presence of Au improves electron–hole separation and suppresses the fluorescence-associated recombination …”

Comparative Studies on Two-Dimensional (2D) Rectangular and Hexagonal Molybdenum Dioxide Nanosheets with Different Thickness

“…The literature suggests some possible reaction mechanism for CVD-grown nanosheets; some of nitrogen gas molecules are converted into ionized nitrogen molecules at specific temperature by thermal irradiation in a tube furnace, and such ionized nitrogen molecules are marked by N Ã 2 [43]. At the desired temperature, the molecules of MoO 3 collide with the ionized N Ã 2 molecules, which produce a series of possible reactions in the presence of inert nitrogen gas environment [44][45][46].…”