Colloidal Synthesis and Characterization of Molybdenum Chalcogenide Quantum Dots Using a Two-Source Precursor Pathway for Photovoltaic Applications

Abstract

The drawbacks of utilizing nonrenewable energy have quickened innovative work on practical sustainable power sources (photovoltaics) because of their provision of a better-preserved decent environment which is free from natural contamination and commotion. Herein, the synthesis, characterization, and application of Mo chalcogenide nanoparticles (NP) as alternative sources in the absorber layer of QDSSCs is discussed. The successful synthesis of the NP was confirmed as the results from the diffractive peaks obtained from XRD which were positive and agreed in comparison with the standard. The diffractive peaks were shown in the planes (100), (002), (100), and (105) for the MoS2 nanoparticles; (002), (100), (103), and (110) for the MoSe2 nanoparticles; and (0002), (0004), (103), as well as (0006) for the MoTe2 nanoparticles. MoSe2 presented the smallest size of the nanoparticles, followed by MoTe2 and, lastly, by MoS2. These results agreed with the results obtained using SEM analysis. For the optical properties of the nanoparticles, UV–Vis and PL were used. The shift of the peaks from the red shift (600 nm) to the blue shift (270–275 nm and 287–289 nm (UV–Vis)) confirmed that the nanoparticles were quantum-confined. The application of the MoX2 NPs in QDSSCs was performed, with MoSe2 presenting the greatest PCE of 7.86%, followed by MoTe2 (6.93%) and, lastly, by MoS2, with the PCE of 6.05%.

Thermophysical Assessments on Self-Assembled Tellurium Nanostructures

“…The peak is seen to be very shallow for 6 h and broadens thereafter. The next peak at 715 cm –1 is attributed to the stretching of the Mo–O–Mo or Mo–O–Te band, and the characteristic peak at 812 cm –1 is ascribed to the vibration of the Mo–Te band . The first two peaks are not prominent for 6 h of reaction time.…”

“…The next peak at 715 cm −1 is attributed to the stretching of the Mo−O−Mo or Mo−O−Te band, 17 and the characteristic peak at 812 cm −1 is ascribed to the vibration of the Mo−Te band. 18 The first two peaks are not prominent for 6 h of reaction time. The peak at 990 cm −1 corresponds to the characteristic stretching vibrations of Mo� O, which is completely absent for 6 h. 17 Furthermore, the two peaks that emerged at ∼1319 and 1600 cm −1 are indicative of the bending vibrations of O−H and N−H, respectively.…”