Wurtzite CuInS2 and CuInxGa1−xS2 nanoribbons: synthesis, optical and photoelectrical properties

Abstract

Single crystalline wurtzite ternary and quaternary semiconductor nanoribbons (CuInS(2), CuIn(x)Ga(1-x)S(2)) were synthesized through a solution-based method. The structure and composition of the nanoribbons were characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), the corresponding fast Fourier transform (FFT) and nanoscale-resolved elemental mapping. Detailed investigation of the growth mechanism by monitoring the structures and morphologies of the nanoribbons during the growth indicates that Cu(1.75)S nanocrystals are formed first and act as a catalyst for the further growth of the nanoribbons. The high mobility of Cu(+) promotes the generation of Cu(+) vacancies in Cu(1.75)S, which will facilitate the diffusion of Cu, In or Ga species from solution into Cu(1.75)S to reach supersaturated states. The supersaturated species in the Cu(1.75)S catalyst, Cu-In-S and Cu-In-Ga-S species, start to condense and crystallize to form wurtzite CuInS(2) or CuIn(x)Ga(1-x)S(2) phases, firstly resulting in two-sided nanoparticles. Successive crystallizations gradually impel the Cu(1.75)S catalyst head forward and prolong the length of the CuInS(2) or CuIn(x)Ga(1-x)S(2) body, forming heterostructured nanorods and thus nanoribbons. The optical band gaps of CuIn(x)Ga(1-x)S(2) nanoribbons can be continuously adjusted between 1.44 eV and 1.91 eV, depending on the Ga concentration in nanoribbons. The successful preparation of those ternary and quaternary semiconductor nanoribbons provide us an opportunity to study their photovoltaic properties. The primary photoresponsive current measurements demonstrate that wurtzite CuIn(x)Ga(1-x)S(2) nanoribbons are excellent photoactive materials. Furthermore, this facile method could open a new way to synthesize other various nano-structured ternary and quaternary semiconductors, such as CuInSe(2) and CuIn(x)Ga(1-x)Se(2), for applications in solar cells and other fields.

Colloidal synthesis of CuGaS x Se 2 − x nanoribbons mediated by Cu 1.75 (SSe) nanocrystals as catalysts

“…The composition of nanoparticle head in the nanoribbons was approximately identified as four elements by EDS, mainly copper, selenium, and sulfur, partially gallium. In our previous work [34], the similar result on the control experiment was achieved. Cu(dedc) 2 was used as precursor in the presence of dodecanethiol and oleylamine, and crystallized Cu 1.75 S (monoclinic, JCPDS No.…”

“…Very recently, the SSS mechanism proposed by Wang [38] for nanowire growth provided the clear understanding about the state and structure of catalysts, whose exceptional catalytic ability originated from high-density vacancies and fast mobility of cations. Since 2008, Cu 2 S [30,31], Cu 1.94 S [32,33], Cu 1.75 S [34], Ag 2 S [35,36] and Ag 2 Se [37][38][39] nanocrystals have been found to be the effective catalysts in solution synthesis of nanowires for their intrinsic nature of fast ionic conductor. As one of the fast ionic conductors, Cu 1.75 (SSe) lattice also has the high-density vacancies and fast mobility of copper cations in the rigid sublattice of Se 2À and S 2À [38], promoting the dissolution of gallium ions and their diffusion from the surface to the interface, which made Cu 1.75 (SSe) nanoparticles act as host.…”

“…In their research, metallic nanoparticles [29], such as Bi and In, usually acted as the catalysts in the growth of 1D nanomaterials. Recently, metal sulfide nanocrystals (Cu 2 S [30,31], Cu 1.94 S [32,33], Cu 1.75 S [34], Ag 2 S [35,36] and Ag 2 Se [37][38][39]) have also been found to be the effective catalysts in solution synthesis of nanowires for the intrinsic nature of fast ionic conductor. Specifically, Wang et al [38] proposed the novel Solution-Solid-Solid (SSS) mechanism for nanowire growth catalyzed by superionic ( for the growth of 1D nanomaterial, especially in the region of the fast ionic conductors.…”

One-pot hydrothermal preparation of wurtzite CuGaS2 and its application as a photoluminescent probe for trace detection of l-noradrenaline

“…Therein, most of the of Cu-based ternary chalcogenides, and has a direct band gap (∼2.4 eV). As a p-type semiconductor, the applications of CuGaS 2 nanomaterials were widely explored in the fields of visible and ultraviolet light-emitting devices [10], thin film solar cell [11], electro-optical devices [12], non-linear devices and detectors [13], photocatalysis [14] etc. However, to the best of our knowledge, there are still limited reports on the application of CuGaS 2 in the field of biological and chemical sensing.…”

Copper‐Based Ternary and Quaternary Semiconductor Nanoplates: Templated Synthesis, Characterization, and Photoelectrochemical Properties

“…However, compared to the common binary chalcogenides, [14] it is still difficult to control the stoichiometry and crystal phase of the ternary and quaternary nanocrystals because of the different reactivity of metal precursors and the complex interactions between the capping molecules and nanocrystals, which may result in the formation of biphasic nanomaterials or heterostructures as the intermediate products. [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] As one of the successful examples for preparing CIS nanostructures, the group of Cui reported the epitaxial growth of CIS nanorods on prenucleated Cu 2 S nanodisks, followed by the progressive transformation of the biphasic Cu 2 S-CIS into monophasic CIS nanorods. [24] Recently, the group of Xie reported that preformed CuSe can be used as a self-sacrificial template for preparation of ultrathin CuInSe 2 nanoplates, but the nanoplates showed small sizes with a broad size distribution.…”