Role of graphene inter layer on the formation of the MoS2-CZTS interface during growth

Abstract

The growth of MoS2 layer near the Mo/CZTS interface during sulphurization process can have an impact on back contact cell parameters (series resistance and fill factor) depending upon the thickness or quality of MoS2. This study reports the dependence of the thickness of interfacial MoS2 layer on the growth of graphene at the interface between molybdenum back contact and deposited CZTS layer. The graphene layer reduces the accumulation of Zn/ZnS, Sn/SnO2 and formation of pores near the MoS2-CZTS interface. The use of graphene as interface layer can be potentially useful for improving the quality of Mo/MoS2/CZTS interface.

One-Step Hydrothermal Synthesis of Cu2ZnSnS4 Nanoparticles as an Efficient Visible Light Photocatalyst for the Degradation of Congo Red Azo Dye

“…To differentiate various phases, the first-order Raman spectra in the 200-400 cm −1 wavenumber region (see Figure 1b) has been analyzed by deconvolution using the Lorentzian peak fitting procedure. Figure 1b shows the presence of a main peak located at 339 cm −1 and a secondary one located at 285 cm −1 which corresponds to A 1 and A vibrational modes of kesterite CZTS, respectively [38,[40][41][42][43]. Thus, the results depicted in Figure 1b can allow us to highlight on one hand that the presence of these features are the characteristic peaks of CZTS and close to the reported values.…”

Simulation of a New CZTS Solar Cell Model with ZnO/CdS Core-Shell Nanowires for High Efficiency

“…Note also that in 2015, by Ansoft HFSS14 simulation on a periodic array of double-shell nanowire structures (ZnO/CdS/CZTS) embedded in a thin multilayer film, Qian Liu et al obtained an absorption rate of about 90% in a range of wavelengths between 400 nm and 1000 nm, i.e., a frequency range of 300 to 750 THz [18,19].As molybdenum (Mo) is widely used as a back contact in CZTS-based cells considering its good electrical properties [20], due to its chemical reaction with CZTS particles, a MoS 2 layer is formed, and voids are observed. Although the formed layer of MoS 2 has a positive effect, the growth of the MoS 2 layer near the Mo/CZTS interface during the sulfurization process can negatively impact the back contact cell parameters (series resistance and fill factor) depending on thickness or quality of MoS 2 [21,22]; it can also be noted that the voids appearing in the MoS 2 /CZTS interlayer generally lead to a degradation of the performance of the solar cell [23].The use of graphene in the Mo/CZTS interface could help us to remedy this problem thanks to these properties [24]. Graphene, although it is not a good absorber, is increasingly used in applications as a twodimensional material to improve surface contacts due to its unique large area properties, electron mobility high, and its superior catalytic capacity [25][26][27][28][29][30].…”

“…This shows that it is interesting to study the optical and electrical performance of the model in which graphene is sandwiched between the core and the shell and also deposited on the MoS 2 layer. Transmission Electron Microscope (TEM) investigations of the two structures, Mo/CZTS and Mo/Graphene/CZTS, were carried out, and the presence of a layer of graphene between Mo and CZTS led to a reduction in thickness from 25% to 33% of the layer of MoS 2 formed; the suppression of the growth of secondary phases near the MoS 2 /CZTS interface has also been observed [24]. Note that very recent research on the growth of MoS 2 -graphene heterostructures at low temperatures has made it possible to know that by depositing a seed layer of a thin film of Mo on graphene followed by an H 2 S sulphurization process, it was possible to obtain an atomic ratio of Mo on S, lower than the stoichiometric value 2 of the MoS 2 standard and, therefore, an improved catalytic performance [39].…”

Rear Interface Modification by the ZnTe Layer Enables High-Efficient Cu2(Zn,Cd)SnS4Thin-Film Solar Cells

“…To resolve the abovementioned problem, physical separation by a rear interface passivation layer between CZTS and Mo is demonstrated to be an effective measure. − Such a layer can not only suppress the detrimental rear interface reaction but also passivate the rear interface if suitable. An excellent passivation layer, namely ZnTe, has already been demonstrated for the back passivation of CdTe thin-film solar cells previously but has not been applied to CZTS thin-film solar cells yet. , As we know, the CZTS owns a similar band structure as CdTe .…”