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From the material science community, metal telluride semiconductor nanostructures have lately attracted a significant quantity of attention. On account of physics associated in quantum confinement, remarkable surface chemistry metal telluride became the most explored group of semiconductor nanomaterials. The intensive concern in this area originates from their exceptional optical, chemical and electronic properties which give rise to their potential use in the field of solar energy conversion, nonlinear optics, catalysis, thermoelectric and magnetic, as well as other areas. In the current review, shape and size‐controlled synthesis strategies, substantial properties and some selected applications for metal telluride nanostructures are highlighted, for the synthesis of nanoparticles each method is favourably analyzed.

A solitary tread hydrothermal synthesis of lead telluride (PbTe) and copper telluride (Cu (2-x) Te) nanoparticles (NP) at 150 o C was carried out using cationic twin tail surfactant (TTS) dimethylenebis (dodecyldimethylammonium bromide) (12-2-12) as capping agent.UV-Vis and X-ray diffraction (XRD) have been employed to elaborate about structural and physicochemical aspects of NPs. The morphology and the capping behaviour have been revealed through scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). Electron micrographs clearly demonstrated the formation of cubic shaped PbTe NPs with average size distribution ≅ 20±5nm. Perversely spherical morphology have been observed for Cu (2-x) Te NPs with average size ≅15 ±6 nm. The interactions of the adsorbed capping surfactant TTS on the metal surface and alignment of the molecules were confirmed from FTIR studies. The crystalline sizes and lattice strain on the peak broadening of the NP have been measured using Williamson-Hall analysis and size-strain plot method. The optical band gap energy of NP, as determined from the absorbance spectrum was 0.5 eV for lead telluride, while that for copper telluride was 3.4 eV owing to quantum confinement driven shift from bulk materials to nanoscale. The electrical conductivity of lead telluride and copper telluride was found to be 0.01-0.07 S cm -1 and 2.18-10.1 S cm -1 , respectively. peak assignments of metal telluride nanomaterials compared with the twin tail surfactant have been arranged in tabular form in the supporting information S1. The XRD, TEM and Optical analysis data is also presented in a separate table S2. This information is available free of charge via the Internet at

Surface-area-controlled porous TiO thin films were prepared via a simple sol-gel chemical route, and their gas-sensing properties were thoroughly investigated in the presence of typical oxidizing NO gas. The surface area of TiO thin films was controlled by developing porous TiO networked by means of controlling the TiO-to-TTIP (titanium isopropoxide, CHOTi) molar ratio, where TiO nanoparticles of size ∼20 nm were used. The sensor's response was found to depend on the surface area of the TiO thin films. The porous TiO thin-film sensor with greater surface area was more sensitive than those of TiO thin films with lesser surface area. The improved sensing ability was ascribed to the porous network formed within the thin films by TiO sol. Our results show that surface area is a key parameter for obtaining superior gas-sensing performance; this provides important guidelines for preparing and using porous thin films for gas-sensing applications.

The construction of dimethylenebis(eicosyldimethylammonium bromide) surfactant-directed gold nanoparticles (NPs) has been accomplished via a one-pot thermal reduction of HAuCl4 with trisodium citrate. The effect of cationic twin-tail surfactants, dimethylenebis(hexadecyldimethylammonium bromide) (16-2-16), dimethylenebis(octadecyldimethylammonium bromide) (18-2-18) and dimethylenebis(eicosyldimethylammonium bromide) (20-2-20), and their concentrations on shape and size of Au nanoparticles was thoroughly investigated. The UV-Vis spectroscopy and transmission electron microscopy (TEM) results show that longer tail length surfactants act as shape-directing agents promoting diversified morphologies. The formation of multiple-shaped Au nanoparticles, such as round, hexagonal, pentagonal, triangular and rod-like, has been confirmed from microstructure analysis; among them, many triangular shapes enhanced at elevated levels of surfactant concentration. In addition, the triangular Au nanoparticles with truncated corners were changed to smooth corners as the hydrocarbon chain length increased from (18-2-18) to (20-2-20). The concentration and hydrocarbon tails of twin-tail surfactants strongly influence the size and structure of Au NPs. In addition, the Au NPs synthesized with the twin-tail surfactant (18-2-18) were found to be highly sensitive towards Hg(2+), which could be because of the preferential adsorption of Hg(0) on the lower energy facets of triangular-shaped Au NPs.

Copper telluride [Cu(2−x)Te] nanoparticles stabilized by highly hydrophobic surfactants were synthesised and their structural, optical and electrical properties were examined.

Nanoscience as a powerful general-purpose technology for commercialization.

A versatile and facile methodology is presented for size-controlled, lead telluride nanoparticles in the presence of highly hydrophobic cationic gemini surfactants (12–2–12, 14–2–14 and 16–2–16) as capping/stabilizing agents.