Synthesis and Characterization of Colloidal CZTS Nanocrystals by a Hot-Injection Method

Abstract

The present study reports the synthesis of colloidal Cu2ZnSnS4(CZTS) nanocrystals (average size ~4–9 nm) by a simple and low cost hot-injection method. These nanocrystals form larger particles with sizes around 40 nm. Oleylamine (OLA) was used as both the solvent and the nanocrystal stabilizer. The effect of the synthesis time on the structural, compositional, morphological, and optical properties was studied. As revealed by XRD, Raman, and TEM measurements all the prepared samples are comprised of both kesterite and wurtzite CZTS nanocrystals. The wurtzite phase contribution reduces as the reaction time is increased. The “bandgap” of the obtained nanoparticles tends to 1.52 eV for the larger synthesis times (24 h) which is suitable for an absorber layer in thin films solar cells.

Synthesis and characterization of sol gel derived nontoxic CZTS thin films without sulfurization

“…The absorption edge obtained from UV‐VIS spectroscopy is linked to the energy band‐gap . The band gap of 3‐LAY, 5‐LAY, and 9‐LAY films (Table ) match well with the corresponding values in literature . It is also observed that the 5‐LAY and 9‐LAY films have lower optical band gap energy in comparison to 3‐LAY film, which may be attributed to the reason that as the thickness of the film decreases, the gap between the conduction and valence band increases due to quantum confinement phenomenon which eventually leads to increment in the band gap value …”

“…This shows that both 5‐LAY and 9‐LAY CZTS films possess crystalline nature with the kesterite structure and matches well with the JCPDS #26‐0575. Prepared 3‐LAY CZTS film is amorphous.…”

Synthesis of Cu2ZnSnS4 (CZTS) Ink by an Easy Hydrothermal Method

“…7 Furthermore, all the constituent elements of CZTS are naturally abundant and cheap, whereas the rare and expensive elements of In and Ga are employed in the well-known material of CuInxGa1-x (S,Se)2 (CIGS / CIGSe). [5][6][7][8] Furthermore, all CZTS constituents are intrinsically abundant and inexpensive. In contrast, the CIGS constituents (In and Ga) are rare and expensive, making it an ideal candidate for producing cost-effective solar cells on a large scale.…”

“…Nowadays, most materials and solvents used in solar cells are not suitable from this point of view. 8,9 The function of a solar cell is highly sensitive to optical and electrical properties, which greatly depends on the crystalline structure and the absorbent material's composition. Therefore, to achieve the desired stoichiometry, understanding and optimizing the growth and formation of phases in photovoltaic materials is highly important.…”

“…11 Although the nonvacuum methods of manufacturing are attractive in terms of their low complex fabrication route, cost ,and scalability, the need for using toxic solvents and organic/metal solutions containing large amounts of pollutants to reduce the causes of cracks during the dissolution process is challenging. [12][13][14][15] Consequently, determining the desired properties of CZTS nanocrystals for inkjet printers requires designing new nanoparticle synthesis methods.…”