Color-Tunable Photoluminescence of Alloyed CdS_xSe_1-x Nanobelts

Abstract

High-quality CdSxSe1-x nanobelts of variable composition (0 </= x </= 1) were fabricated by a simple one-step thermal evaporation route. Photoluminescence measurements showed that all the CdSxSe1-x nanobelts have a single near-bandedge emission band, and their spectral maximum positions can be tuned from approximately 508 nm (for pure CdS) to approximately 705 nm (for pure CdSe). These kinds of nanobelts may have potential applications in adjustable nano/micro photoelectric devices in the visible region.

Electronic structure and optical properties of CdSxSe1−x solid solution nanostructures from X-ray absorption near edge structure, X-ray excited optical luminescence, and density functional theory investigations

“…One goal is to have the ability to control the composition of semiconductor alloys and effectively tune the band-gap of a material for a specific function. As a result, various ternary alloys have recently attracted a great deal of attention for their ability to achieve a wide range of band-gaps, [1][2][3][4][5][6][7][8][9][10][11][12] Additionally, nano-materials, such as nano-wires and nano-ribbons, offer greater versatility by providing a wider range of alloy composition and band-gap modulation which is unachievable using traditional epitaxial film materials due to lattice strain at the substrate interface. 13 Ternary chalcogenide semiconductors, particularly cadmium sulpho-selenide (CdS x Se 1Àx ) alloys, have been intensely studied 8,[14][15][16][17][18][19] in part due to the remarkably broad range of stable stoichiometries that can be attained, owing to the small lattice mismatch among the constituent anions.…”

“…A variety of CdS x Se 1Àx alloy nano-material morphologies have been synthesized, including nano-wires, nano-ribbons, nano-belts, nano-sheets, nano-crystals, and nano-particles with a variety of aspect ratios and stoichiometries. 3,14,16,18,19 The diversity of electronic and spectral properties of CdS x Se 1Àx alloy nanostructures has great potential applications in tunable optoelectronic devices, such as color engineered displays and lighting, 19 multi-spectral detectors, 13 full-spectrum solar cells, 23 and broadly tunable nanolasers. 8,15,24 Therefore, a detailed examination of the electronic structure and corresponding optical emission is essential to determine the full potential of these functional materials.…”

Synthesis of Semiconducting Functional Materials in Solution: From II‐VI Semiconductor to Inorganic–Organic Hybrid Semiconductor Nanomaterials

“…[40][41][42][43][44][45][46][47] On the other hand, hybrid structures consisted of semiconducting organic slabs and strongly luminescent II-VI semiconductor nanostructures offer favorable perspectives through highly saturated, tunable optical properties, in combination with an easy process-ability from solution and low cost of precursors, which is of importance for high-tech applications such as hybrid organic-inorganic light-emitting diodes and solar cells. [48][49][50] In recent years, novel nanostructures of functional II-VI semiconductor chalcogenides, including nanobelts, nanowires, nanosaws, nanocombs and nanowindmills have been synthesized using thermal evaporation method by Wang's group [42,44,[51][52][53][54][55][56][57][58][59][60] and Lee's group. [61][62][63][64][65][66] In contrast to the traditional thermal evaporation routes or chemical vapor deposition (CVD) method, even hard template approaches, solution chemistry based so-called ''soft'' approaches can provide an alternative, convenient, lower temperature, and environmentally friendly pathway for fabrication of advanced inorganic materials with desirable shapes and sizes, [67] which do not rely on drastic conditions (i.e., high temperature, high pressure etc.…”

Tunable and Predetermined Bandgap Emissions in Alloyed ZnSxSe1–x Nanowires

“…[10,11] Furthermore, the previous studies show that the variation of E g (AB x C 1-x ) can be represented as a quadratic function of composition…”

“…[18,19] It is suggested that the composition of Zn x Cd 1-x S and CdS x Se 1-x nanobelts is highly dependent on the substrate temperature. [10,11] In our experiment, the silicon substrates were perpendicularly but not horizontally placed on the ceramic boat (see the Experimental Sec. ), and homogeneous composition was obtained on each substrate.…”