The in situ synthesis of PbS nanocrystals from lead(II) n-octylxanthate within a 1,3-diisopropenylbenzene-bisphenol A dimethacrylate sulfur copolymer

Semiconductor Deposition via Laser Printing of a Bespoke Toner Containing Metal Xanthate Complexes

A methodology to use laser printing, a form of electrophotography, to print metal chalcogenide complexes on paper, is described. After fusing the toner to paper, a heating step is used to cause the printed metal xanthate complexes to thermolyze within the toner and form three target metal chalcogenides: CuS, SnS, and ZnS. To achieve this, we synthesize a poly(styrene-co-n-butyl acrylate) thermopolymer that emulates the thermal properties of a commercial toner and is also solution processable with the metal xanthate complexes used: [Zn(S2COEt)2], [Cu(S2COEt)·(PPh3)2], and [Sn(S2COEt)2]. We demonstrate through energy dispersive X-ray mapping that the toner is deposited following printing and that thermolysis of the metal xanthate complexes occurs in the fused toner, demonstrating the first example of laser printing of inorganic complexes and, in turn, semiconductors.

Characterization of lead sulfide obtained from Naga Bhasma

BACKGROUND

Lead sulfide nanoparticles were manufactured from lead oxide using a procedure described in the Ayurveda formulary of India, which involved using a quantum of the heat of up to 60 puta, which is officially known as the Shasti puta Naga Bhasma.

OBJECTIVE

The study shows sulfurization of nanoparticles decreased their toxicity due to the lower solubility.

MATERIALS AND METHODS

The present work used the arsenic sulfide media and traditional puta for processing and the characterization of the same has been conducted. Different analytical techniques like X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-Ray (EDX) spectroscopy, Fourier transform infrared spectroscopy (FTIR), and thermo-gravimetry analysis (TGA) were used.

RESULTS

Powder x-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, Thermogravimetric analysis, and differential thermal analysis all showed that the produced nanoparticles are lead sulfide nanoparticles with a particle size of an average of 84.60 and the crystalline average size of 69.06 nm.

CONCLUSION

The rounded, rod, oval, cubic, and circular morphology of the produced lead sulfide nanoparticles can be seen in the SEM image. The stretching and bending functional groups in the sample were alkanes, alkenes, aromatic hydrocarbons, carboxylic acids, alkyl carboxylic acids, alkyl alpha, beta-unsaturated, aldehydes, ketones, carboxylic acid, aliphatic amines, primary amines, secondary amines, alkyl halides, are studied through the FTIR spectrum.

Structural Investigations of α-MnS Nanocrystals and Thin Films Synthesized from Manganese(II) Xanthates by Hot Injection, Solvent-Less Thermolysis, and Doctor Blade Routes

Manganese(II) xanthate complexes of the form [Mn(S2COR)2(TMEDA)], where TMEDA = tetramethylethylenediamine and R = methyl (1), ethyl (2), n-propyl (3), n-butyl (4), n-pentyl (5), n-hexyl (6), and n-octyl (7), have been synthesized and structures elucidated using single-crystal X-ray diffraction. Complexes 1-7 were used as molecular precursors to synthesize manganese sulfide (MnS). Olelyamine-capped nanocrystals have been produced via hot injection, while the doctor blading followed by thermolysis yielded thick films. Free-standing polycrystalline powders of MnS are produced by direct thermolysis of precursor powders. All thermolysis techniques produced cubic MnS, as confirmed by powder X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Raman spectroscopy. Magnetic measurements reveal that the α-MnS nanocrystals exhibit ferromagnetic behavior with a large coercive field strength (e.g., 0.723 kOe for 6.8 nm nanocrystals).

Accessing γ-Ga2S3 by solventless thermolysis of gallium xanthates: a low-temperature limit for crystalline products

Alkyl-xanthato gallium(iii) complexes of the form [Ga(S₂COR)₃], where R = Me (1), Et (2), ⁱPr (3), ⁿPr (4), ⁿBu (5), ^sBu (6) and ⁱBu (7), have been synthesized and fully characterised. The crystal structures for 1 and 3-7 have been solved and examined to elucidate if these structures are related to their decomposition. Thermogravimetric analysis was used to gain insight into the decomposition temperatures for each complex. Unlike previously explored metal xanthate complexes which break down at low temperatures (<250 °C), to form crystalline metal chalcogenides, powder X-ray diffraction measurements suggest that when R ≥ Et these complexes did not produce crystalline gallium sulfides until heated to 500 °C, where γ-Ga₂S₃ was the sole product formed. In the case of R = Me, Chugaev elimination did not occur and amorphous Ga_xS_y products were formed. We conclude therefore that the low-temperature synthesis route offered by the thermal decomposition of metal xanthate precursors, which has been reported for many metal sulfide systems prior to this, may not be appropriate in the case of gallium sulfides.

Lead ethyl dithiocarbamates: efficient single-source precursors to PbS nanocubes

Lead ethyl dithiocarbamates have been successfully used as single-source precursors for the deposition of PbS using spin coating followed by annealing at moderate temperatures. The thin films were characterized using a powder X-ray diffractometer and were found to be face-centred cubic with the (200) plane being the most preferred orientation. Scanning electron microscopy images showed the formation of well-defined cubes. Optical band gaps of PbS thin films were estimated using Tauc plots as 0.72, 0.73 and 0.77 eV at annealing temperatures of 250, 300 and 400°C. These band gaps were all blue shifted from the bulk value of 0.41 eV. Energy-dispersive X-ray analysis was used to determine the composition of the thin films which showed an approximately 1 : 1 Pb to S ratio.

Synthesis and Applications of Polymers Made by Inverse Vulcanization

Elemental sulfur is an abundant and inexpensive chemical feedstock, yet it is underused as a starting material in chemical synthesis. Recently, a process coined inverse vulcanization was introduced in which elemental sulfur is converted into polymers by ring-opening polymerization, followed by cross-linking with an unsaturated organic molecule such as a polyene. The resulting materials have high sulfur content (typically 50-90% sulfur by mass) and display a range of interesting properties such as dynamic S-S bonds, redox activity, high refractive indices, mid-wave IR transparency, and heavy metal affinity. These properties have led to a swell of applications of these polymers in repairable materials, energy generation and storage, optical devices, and environmental remediation. This article will discuss the synthesis of polymers by inverse vulcanization and review case studies on their diverse applications. An outlook is also presented to discuss future opportunities and challenges for further advancement of polymers made by inverse vulcanization.

Recent advances in the polymerization of elemental sulphur, inverse vulcanization and methods to obtain functional Chalcogenide Hybrid Inorganic/Organic Polymers (CHIPs)

Recent developments in the polymerization of elemental sulfur, inverse vulcanization and functional Chalcogenide Hybrid Inorganic/Organic Polymers (CHIPs) are reviewed.

Full compositional control of PbSxSe1-x thin films by the use of acylchalcogourato lead(ii) complexes as precursors for AACVD

Selenium and sulfur derivatives of lead(ii) acylchalcogourato complexes have been used to deposit PbSxSe1-x thin films by AACVD. By variation of the mole ratio of sulfur and selenium precursors in the aerosol feed solution the full range of compositions of PbSxSe1-x was obtained, i.e. 0 ≥ x ≥ 1. The films showed no contaminant phases demonstrating the potential for acylchalcogourato metal complexes as precursors for metal chalcogenide thin films. The crystal structure for bis[N,N-diethyl-N'-2-naphthoylthioureato]lead(ii) was solved and displayed the expected decreases in Pb-E bond lengths from the previously reported selenium variant.