Single-source Precursor Research Articles

MXene-Derived Oxide Nanoheterostructures for Photocatalytic Sulfamethoxazole Degradation.

Herein, we report for the first time the use of ternary oxide nanoheterostructure photocatalysts derived from (Nb y , Ti1-y )2CT x MXene in the treatment of water. Three different compositions of binary MXenes, viz., (Ti0.75Nb0.25)2CT x , (Ti0.5Nb0.5)2CT x , and (Ti0.25Nb0.75)2CT x (with T x = OH, F, and Cl), were used as single-source precursor to produce TiNbO x -3:1, TiNbO x -1:1, and TiNbO x -1:3 by controlled-atmosphere thermal oxidation. Phase identification and Le Bail refinements confirmed the presence of a mixture of rutile TiO2 and monoclinic Ti2Nb10O29. Morphological investigations through scanning and transmission electron microscopies revealed the retention of layered nanostructures from the MXene precursors and the fusion of TiO2 and Ti2Nb10O29 nanoparticles in forming nanosheets. Among the three oxide nanoheterostructures, TiNbO x -3:1 exhibited the best photocatalytic performance by the removal of 83% of sulfamethoxazole (SMX) after 2 h of reaction. Such a result is explained by a complex influence of structural, morphological, and electronic properties since TiNbO x -3:1 consisted of small-sized crystallites (40-70 nm) and possessed a higher surface area. The suggested electronic band structure is a type-II heterojunction, where the recombination of electrons and holes is minimized during photocatalytic reactions. The photocatalytic degradation of SMX was promoted by the attack of •OH, as evidenced by the detection of 2.2 μM •OH, using coumarin as a probe. This study highlights the potential application of MXene-derived oxide nanoheterostructures in wastewater treatment.

Laser-Induced Synthesis of Tin Sulfides.

Various polytypes of van der Waals (vdW) materials can be formed by sulfur and tin, which exhibit distinctive and complementary electronic properties. Hence, these materials are attractive candidates for the design of multifunctional devices. This work demonstrates direct selective growth of tin sulfides by laser irradiation. A 532nm continuous wave laser is used to synthesize centimeter-scale tin sulfide tracks from single source precursor tin(II) o-ethylxanthate under ambient conditions. Modulation of laser irradiation conditions enables tuning of the dominant phase of tin sulfide as well as SnS2/SnS heterostructures formation. An in-depth investigation of the morphological, structural, and compositional characteristics of the laser-synthesized tin sulfide microstructures is reported. Furthermore, laser-synthesized tin sulfides photodetectors show broad spectral response with relatively high photoresponsivity up to 4 AW-1 and fast switching time (τ rise = 1.8ms and τ fall = 16ms). This approach is versatile and can be exploited in various fields such as energy conversion and storage, catalysis, chemical sensors, and optoelectronics.

Microstructure, mechanical properties, and wettability of CrN and CrSiCN coatings with graded architectures

Protective CrN-based coatings are of interest for applications requiring a combination of corrosion resistance and toughness. Here, the processing-microstructure-properties relationships for metallic Cr, binary CrN, and quaternary CrSiCN coatings are reported. Hexamethyldisilazane (HMDS) was used as a single-source organosilicon precursor for Si and C during plasma-enhanced magnetron sputtering (PEMS). By varying the availability of reactive species during coating growth, graded coating architectures were produced. Scanning and transmission electron microscopy revealed that as Si and C content increased, the coating microstructure evolved from a coarse, columnar growth structure (0 at.% Si), to a nanocolumnar structure (3 at.% Si), and, finally, to a dense, nanoscale structure (6 at.% Si). Coating surface topography was characterized using optical microscopy and atomic force microscopy. While the CrSiCN coating deposited at the highest HMDS flow rate exhibited the lowest nanoscale surface roughness (Rq = 6.74 nm), it also had the greatest area fraction of microscopic surface defects. Evidence of the formation of secondary Cr2N phases within the graded interlayers of the coatings was acquired from selected area electron diffraction analysis. However, the practical adhesion of the coatings, as evaluated by the Rockwell C indentation test, was not adversely affected. Nanoindentation testing revealed that greater incorporation of Si and C into the CrN-based coatings increased coating hardness from 25.4 ± 1.6 GPa to 30.7 ± 1.8 GPa and decreased apparent elastic modulus from 295 ± 14 GPa to 284 ± 12 GPa. Contact angle goniometry was conducted to determine the wettability of the coatings. It was found that sessile water contact angles decreased from 86.5° ± 1.6° to 77.3° ± 2.1° as coating Si and C content increased.

Deciphering the energy storage and electro‐catalytic potential of the BaLa2MnS5 ternary metallic sulfide prepared via single source precursor route

AbstractThe present work elucidates the first report on the synthesis and energy applications of the novel BaLa2MnS5 prepared from single source precursor route. This metal chalcogenide expressed a tuned band gap of 3.84 eV and an average crystallite size of 20.52 nm. Functional groups explored for BaLa2MnS5 expressed strong signals for presence of the metal sulfide bonds. The thermal decomposition pattern of BaLa2MnS5 followed a two‐phased mechanism. Synthesized metal sulfide possessed an irregular morphology with particles arranged in random manner. An assessment of the chalcogenide BaLa2MnS5 for energy applications has been carried out. When employed as an electrode material in 1 M KOH, which acted as the background electrolyte, BaLa2MnS5 chalcogenide showed a specific capacitance of 597 F g−1. Furthermore, this BaLa2MnS5 chalcogenide decorated electrode has a low resistance, as shown by the Rs of 1.35 Ω, and a specific power density of 7366 W kg−1, according to the impedance investigations. The electrochemical results for the OER activity are indicative of the OER overpotential and Tafel slope values as 388 mV and 108 mV/dec. This electrode achieved the HER overpotential value of 241 mV while the obtained Tafel slope was 194 mV/dec.

Enhancing electrical properties of SiHfBCN ceramics through Cu-catalyzed polymer-derived ceramic synthesis

In this study, we employed Cu-catalyzed polymer-derived ceramic methods at lower temperatures to synthesize SiHfBCN ceramics. The SiHfBCN-Cu single-source precursors were characterized using Fourier Transform-Infrared Spectrometry and thermal gravimetric analysis, while X-ray diffraction, X-ray photoelectron spectroscopy, Raman Spectrometer, transmission electron microscopy, and a four-point probe setup were utilized to investigate composition, microstructural evolution, and electrical conductivity. Our analysis revealed that the electrical conductivity of SiHfBCN-Cu ceramics, annealed at 1500 °C, reached an impressive 2409.6 S·m-¹. This improvement was attributed to the influence of pyrolysis temperature and Cu content, resulting in the formation of in-situ abundant graphite-like carbon, Cu nano crystallites and Hf1-xCuxC@C and SiC@C nanoparticles with core-shell structures constructed a three-dimensional conductive network. Importantly, Cu-catalyzed SiHfBCN ceramics at lower temperatures produced an abundance of graphite-like carbon ribbons, effectively enhancing their electrical conductivity. These findings highlight the potential of Cu-catalyzed SiHfBCN ceramics as high-temperature sensors for in-situ measurements in extreme environments.

Advanced Molecular Layer Deposition of SixZnyOz Thin Film Coatings for Improved Electrochemical Performance of NMC811

AbstractThe practical realization of Nickel‐rich layered oxide cathode materials such as LiNi0.8Mn0.1Co0.1O2 (NMC811) is hampered by several structural and interfacial instabilities over prolonged cycling. Several reports have proposed surface passivation via an artificial cathode electrolyte interphase (ACEI) as a promising method for mitigating the parasitic reactions affecting NMC811 while simultaneously improving its electrochemical performance over prolonged cycling. Herein, we report an in‐house designed (tBuMe2Si)2Zn single source precursor for developing SixZnyOz ternary CEI thin films on NMC811 via molecular layer deposition (MLD) in combination with O3 or H2O as oxidizing agent. We demonstrate that the single precursor (tBuMe2Si)2Zn avoids the need for two different precursors (Si & Zn). In‐depth spectroscopic studies reveal the mechanism of the formation of organosiloxane/zinc‐oxide composite thin film, via intermediates of unprecedented organo‐silicon‐zinc compounds. Understanding the reaction mechanism paved the path for a successful deposition of ACEI on NMC811. Rate capability studies shows the ACEI protected cathodes exhibit higher discharge capacity at 4 C than pristine NMC811. Furthermore, studies on full cells with graphite anode were conducted to evaluate the practical viability of SixZnyOz ACEI thin films on NMC811. After prolonged cycling the ACEI‐coated NMC811 full cells significantly improved the electrochemical performance than pristine NMC811 by ~12%.

Photostimulated Pyrothermoelectric Coupling in Two-Dimensional Tin Monoselenide Enabling Zero-Biased Multimodal Transducers.

Despite the advancement of the Internet of Things (IoT) and portable devices, the development of zero-biased sensing systems for the dual detection of light and gases remains a challenge. As an emerging technology, direct energy conversion driven by intriguing physical properties of two-dimensional (2D) materials can be realized in nanodevices or a zero-biased integrated system. In this study, we unprecedentedly attempted to exploit the photostimulated pyrothermoelectric coupling of two-dimensional SnSe for use in zero-biased multimodal transducers for the dual detection of light and gases. We synthesized homogeneous, large-area 6 in SnSe multilayers via a rational synthetic route based on the thermal decomposition of a solution-processed single-source precursor. Zero-biased SnSe transducers for the dual monitoring of light and gases were realized by exploiting the synergistic coupling of the photostimulated pyroelectric and thermoelectric effects of SnSe. The extracted photoresponsivity at 532 nm and NO2 gas responsivity of the SnSe-based transducers corresponded to 1.07 × 10-6 A/W and 13263.6% at 0 V, respectively. To bring universal applicability of the zero-biased SnSe transducers, the wide operation bandwidth photoelectrical properties (visible to NIR) and dynamic current responses toward two NO2/NH3 gases were systematically evaluated.

Experimental verification of double-four-ring-type aluminosilicate molecule as a single-source precursor for zeolite synthesis

Abstract While a variety of functional zeolites have been synthesized using hydrothermal methods with conventional discrete Al and Si sources, control of the composition, structure, and function of the targeted zeolites often involves expensive and time-consuming trial-and-error approaches. Despite ongoing efforts to manipulate zeolite formation by adjusting Al and Si sources and reaction conditions, limited attention has been given to studies on zeolite synthesis using molecular precursors (MPs) with preorganized Al–O–Si bonds. Here, we demonstrate the synthesis of LTA-type zeolites using [TMA]4[Al4Si4O12(OH)8]·13H2O ([MP]; TMA = tetramethylammonium cation) with a double-four-ring (D4R)-type core structure, which is known to be a secondary building unit in the LTA-type zeolite, as a MP. Here, we demonstrate the successful synthesis of LTA-type zeolites using [MP] under hydrothermal conditions at 100 to 200 °C in the presence of 1 equiv. of NaOH or NaCl. Notably, when discrete Al and Si sources were used instead of [MP] under otherwise identical conditions (the same Si/Al ratio, Na+ content, and temperature), GIS-, SOD-, and FAU-type zeolites lacking the D4R structure were obtained in addition to the LTA-type zeolites.

Hot injection synthesis of CuS decorated CdS and ZnS nanomaterials from metal thiosemicarbazone complexes as single source precursors: Application in the photocatalytic degradation of methylene blue

CdS and ZnS are considered excellent semiconductors for photocatalysis, but photocorrosion and low photocatalytic activity limit their practical application. In order to improve on their photocatalytic activities, Copper sulfide-decorated CdS and ZnS (CuS@CdS and CuS@ZnS) nanocomposites were synthesized from Cu(II), Zn(II) and Cd(II) complexes of 2–(phenyl(pyridin–2–yl)methylene)hydrazine–1–carbothioamide, as single source precursors using a facile hot injection method at 250 °C, employing olive oil as capping agent. The structure, morphology, and optical properties of the as-prepared nanocomposites were determined using various analytical techniques. The results of powder X-ray diffraction (p-XRD), energy dispersive X-ray spectroscopy (EDX) and elemental mapping showed the presence of CuS, CdS and ZnS in CuS@CdS and CuS@ZnS, confirming the formation of nanocomposites. Transmission Electron Microscopy (TEM) images show agglomeration of CuS nanoparticles on the surface of CdS and ZnS nanoparticles. Scanning electron microscopy (SEM) images of CuS@CdS and CuS@ZnS nanocomposites revealed an agglomerated flower-like structure with porous surface. The band gap energies of 2.84 eV and 3.12 eV for CuS@CdS and CuS@ZnS, respectively, obtained from Tauc plots, demonstrate that combining CuS with single CdS and ZnS has an effect on their optical properties which probably account for the improved photocatalytic responses. The photocatalytic performance of the as-prepared materials was evaluated using the photodegradation of methylene blue (MB) dye under UV light irradiation. Results show that the degradation efficiencies for CuS@CdS (57 %) and CuS@ZnS (65 %) nanocomposites exhibited higher photocatalytic activity compared to those of pure CuS (42.0 %), CdS (35.1 %) and ZnS (57 %), suggesting that thiosemicarbazone complexes can be used as precursors for the development of metal sulphide nanocomposites as useful photocatalysts for the degradation of organic pollutants.

Carbon-Rich Plasma-Deposited Silicon Oxycarbonitride Films Derived from 4-(Trimethylsilyl)morpholine as a Novel Single-Source Precursor.

4-(trimethylsilyl)morpholine O(CH2CH2)2NSi(CH3)3 (TMSM) was investigated as a single-source precursor for SiCNO films synthesis. Optical emission spectroscopy of plasma generated from TMSM/He, TMSM/H2, and TMSM/NH3 gas mixtures revealed the presence of N2, CH, H, CN, and CO species. The last two are suggested to be responsible for the lowering of carbon concentration in the films in comparison with the precursor. The refractive index ranged from 1.5 to 2.0, and bandgap varied from 2.0 to 4.6 eV, which pointed that some of the films can be used as antireflective coatings in silicon photovoltaic cell technologies and dielectric layers in electronic devices.

Solventless Synthesis of Zinc Sulphide Nanoparticles from Zinc Bis(diethyldithiocarbamate) as a Single Source Precursor.

This study explores the synthesis of nanoparticles through the thermal decomposition of single-source precursors, a method gaining popularity due to its low cost, minimal environmental toxicity, rapidity, scalability, and the ability to form nanoparticles with few defects. Zinc ethyl carbamate was synthesized and characterized using 1HNMR and infrared spectroscopy. Its purity was confirmed through microelemental analysis and melting point determination. The melting point of the complex was determined to be 165 °C. The thermogravimetric analyses indicated a one-step decomposition of zinc ethyl carbamate with a decomposition onset of of 200 °C, yielding a stable ZnS residue. Further thermal decomposition led to the formation of wurtzite phase ZnS nanoparticles, as evidenced by XRD. SEM micrographs displayed mixed spherical, and cubic unevenly sized, polydispersed nanoparticles, while EDX revealed approximately a 1 : 1 Zn to S ratio. Estimated band gap from the Tauc's plot gave 3.93 eV and 3.42 eV for the nanoparticles synthesized at 300 and 400 °C respectively. The wide difference in the band gaps may be as a result of the larger particles observed at 400 °C and the deformations in the sample as observed in the SEM.

Single Source Precursor Synthesis of Lead Titanate (PbTiO3) for the Electrochemical Detection of Nitric Oxide (NO)

Electrochemical detection of Nitric oxide (NO) has attracted considerable attention due to its central role in different processes of mammalian physiology. In this study, NO is electrochemically detected using lead titanate (PbTiO3) as an electrochemical sensor. The lead titanate (PbTiO3) was prepared successfully through thermal decomposition of bimetallic complex [PbTi(O2CCF3)4(THF)3O]2 containing both lead and titanium metals. A phase of synthesized PbTiO3 powder was studied using X-ray diffraction spectroscopy and Raman spectroscopy, while the morphology and crystallite size were studied by field emission scanning electron microscopy and high-resolution transmission electron microscopy. Further, X-ray photoelectron spectroscopy analysis was also done to determine the elemental composition along with their oxidation states. Finally, the PbTiO3 powder was coated on GCE (glassy carbon electrode) and then further studied electrochemically for sensing NO in NaNO2 solution at pH = 2.5. Moreover, the detection capability of PbTiO3 was analyzed upon adding different concentrations of 1 to 10 mM of NaNO2. As a result, current and concentration followed a linear response. For the interferent studies, uric acid, glucose, dopamine, and ascorbic acid were used as interferents. It was noted that no signals appeared with these interferents in the voltammogram.

Tailoring crystal structure of high-entropy carbides in Si-based ceramic nanocomposites through precursor engineering

High-entropy carbides with tunable crystallization and growth have been demonstrated using single-source precursor derived ceramic route. The in situ nanocrystallization of high-entropy carbide phases, (Ta0.2W0.2V0.2Mo0.2Nb0.2)SiδC and (Ta0.167W0.167V0.167Mo0.167Nb0.167Si0.167)C in amorphous Si-based ceramic matrices was achieved by using polysiloxanes and polycarbosilanes as polymer precursors respectively. The results exemplify a prominent role of the architectures of the polymeric precursors in controlling the structural features of these ceramics at various length scales. In particular, it was observed that high-entropy carbides with rock salt and zinc blende crystal structures were formed when polysiloxanes and polycarbosilanes with different backbone structure were used as polymeric precursors respectively. This is attributed to the thermodynamics of nucleation of the carbidic phases in these nanocomposites. Furthermore, the precursor architecture that dictates free carbon content, influenced nanostructural features and porosity in the material. Therefore, engineering such compositionally complex phases is feasible by selecting suitable polymeric precursors.

From energy to environmental solutions: Harnessing ZrS:BaS:Ni9S8 thin film for supercapacitor and water purification

The present study aims to provide a comprehensive analysis on thin film, ZrS:BaS:Ni9S8. ZrS:BaS:Ni9S8 thin film was fabricated in a resistive heating unit from a single source precursor. With 21 nm crystallite size for ternary metal sulfide through XRD, a 2.5 eV optical band gap was elucidated. The chemical composition was assessed by the X-ray photoelectron spectroscopy, which revealed core level peaks associated with Zr3d, S2p, Ba3d and Ni2p. A remarkable specific capacitance value of 540.7 F g−1 was assessed through cyclic voltammetry. This notable performance, coupled with the thin film's excellent cycling stability, established the thin film as a capable contender for diverse applications of energy retention. Moreover, a comprehensive investigation on the removal through photocatalysis of environmental pollutants; zoxamide, methylene blue, and phenol was done. The pesticide zoxamide depicted the degradation rate constant 3.9 × 10−2 min−1. The results present persuasive proof of the multifaceted opportunities presented by the ZrS:BaS:Ni9S8 thin film, outspreading its application outside energy retention to incorporate innovative functionalities.

Fluidized Bed Chemical Vapor Deposition on Hard Carbon Powders to Produce Composite Energy Materials.

Herein, we report a general route for the uniform coating of hard carbon (HC) powders via fluidized bed chemical vapor deposition. Carbon-based fine powders are excellent substrate materials for many catalytic and electrochemical applications but intrinsically difficult to fluidize and prone to elutriation. The reactor was designed to achieve as much retention of powders as possible, supported by a computational fluid dynamics study to assess the hydrodynamic behavior for varying gaseous flow rates. Solutions of the tin seleno- and thio-ether complexes [SnCl4{nBuSe(CH2)3SenBu}] and [SnCl4{nBuS(CH2)3SnBu}] were used as single source precursors and injected at high temperature into a fluidized bed of HC powders under nitrogen flow. The method allowed for the synthesis of HC-SnSx-SnSe2 composites at the gram scale with potential applications in electrocatalysis and sodium-ion battery anodes.

Facile one-step preparation of Co2CrO4 spinel from heterometallic compounds – Structural, magnetic, electrical and photocatalytic studies

Two isostructural heterometallic complex salts with mononuclear units, [NH(CH3)2(C2H5)][Cr(terpy)2][CoCl4]2 (1) and [NH(CH3)(C2H5)2][Cr(terpy)2][CoCl4]2 (2), were synthesized using a building block approach and characterized by single-crystal and powder X-ray diffraction (XRD), impedance spectroscopy and magnetization measurements. They exhibit particular humidity-sensing properties and very high proton conductivity at room temperature. The magnetization of complexes shows the high spin state of 3/2 for tetrahedrally coordinated CoII ions, which on cooling remain in the paramagnetic state within the CrIII network, which is antiferromagnetically correlated. The prepared compounds were thoroughly explored as single-source precursors for the formation of the spinel oxide Co2CrO4 by their thermal decomposition. By optimizing the annealing temperature, heating/cooling rates and holding times, the phase composition of thermal processing of 1 or 2 was evaluated: phase pure spinel Co2CrO4 was obtained by thermal treatment already at 450 °C. The structure, morphology, and optical properties of spinel oxides prepared at different temperatures were characterized using powder XRD, field emission scanning electron microscopy (SEM) and UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS), while electrical and magnetic by impedance spectroscopy and magnetization measurements. The determined band gap energy and nanosized crystallites prompted us to investigate the photocatalytic activity of spinel oxide produced at 450 °C in the degradation of dyes Rhodamine B (RhB) and Methylene blue (MB) under Vis irradiation without and with assistance of hydrogen peroxide (H2O2). The results show that the Co2CrO4/H2O2 system exhibits a significantly higher photoactivity response; the degradation efficiency of MB and RhB was found to be 86.1% and 80.3%, respectively. The electrical conductivity spectra and the activation energy for the DC conductivity demonstrate the electronically semiconducting behaviour of the Co2CrO4 oxide. The Co2CrO4 spinel has a ferrimagnetic ground state, with mixed CoII and CoIII ions on the tetrahedral and octahedral sites: CoII having a high spin state on both sites and CoIII having a high spin state on the tetrahedral site and a low spin state on the octahedral site. Different thermal treatments affect the magnetization according to the different sizes of the obtained crystallites.

Unveiling the Nanocluster Conversion Pathway for Highly Monodisperse InAs Colloidal Quantum Dots.

Colloidal quantum dots (CQDs) have garnered significant attention in nanoscience and technology, with a particular emphasis on achieving high monodispersity in their synthesis. Recent advances in understanding the chemistry of reaction intermediates such as magic-sized nanoclusters (MSC) have paved the way for innovative synthetic strategies. Notably, monodisperse CQDs of various compositions, including indium phosphide, indium arsenide, and cadmium chalcogenide, have been successfully prepared using nanocluster intermediates as single-source precursors. Still, the early stage conversion chemistry of these nanoclusters preceding CQD formation has not been fully unveiled yet. Herein, we report the first-order conversion of amorphous nanoclusters (AMCs) to InAs MSCs prior to the formation of CQDs. We find that MSC, isolated via gel-permeation chromatography, is more stable than purified AMCs, as demonstrated in various chemical and thermolytic reactions. While the surface of InAs AMCs and MSC is similarly bound with carboxylate ligands, detailed structural analyses employing synchrotron X-ray scattering and X-ray absorption spectroscopy unveil subtle distinctions arising from the distinct surface properties and structural disorder characteristics of InAs nanoclusters. We propose that InAs AMCs undergo a surface reduction and structural ordering process, resulting in the formation of an InAs MSC in a thermodynamically local minimum state. Furthermore, we demonstrate that both types of nanoclusters serve as viable precursors, providing a similar monomer supply rate at elevated temperatures of around 300 °C. This study offers invaluable insights into the interplay of structure and chemical stability in binary nanoclusters, enhancing our ability to design these nanoclusters as precursors for highly monodisperse CQDs.

LiNbO3 Thin Films through a Sol-Gel/Spin-Coating Approach Using a Novel Heterobimetallic Lithium-Niobium Precursor.

Lithium niobate is a lead-free material which has attracted considerable attention due to its excellent optical, piezoelectric, and ferroelectric properties. This research is devoted to the synthesis through an innovative sol-gel/spin-coating approach of polycrystalline LiNbO3 films on Si substrates. A novel single-source hetero-bimetallic precursor containing lithium and niobium was synthesized and applied to the sol-gel synthesis. The structural, compositional, and thermal characteristics of the precursor have been tested through attenuated total reflection, X-ray photoelectron spectroscopy, thermogravimetric analysis, and differential scanning calorimetry. The LiNbO3 films have been characterized from a structural point of view with combined X-ray diffraction and Raman spectroscopy. Field-emission scanning electron microscopy, energy dispersive X-ray analysis, and X-ray photoelectron spectroscopy have been used to study the morphological and compositional properties of the deposited films.

Synthesis and Photocatalytic Activity of High-Quality Lead(II) Sulfide Nanoparticles from Lead(II) Thiosemicarbazone Complexes as Single Source Precursors

We report the synthesis of lead(II) complexes of 2-(thiophen-2-ylmethylene) hydrazine-1-carbothioamide (1) and 2-(1-(thiophen-2-yl) ethylene) hydrazine-1-carbothioamide (2), which were used as single source precursors in hexadecylamine (HDA) and oleylamine (OLA) at 190, 230, and 270°C to synthesize lead(II) sulfide nanoparticles. Optical studies by UV–vis analysis showed a general blue shift in the absorption band edge of the PbS nanoparticles (NPs) with energy bandgaps determined by Tauc’s plots ranging from 2.15 to 3.11 eV. The development of NPs with a variety of morphologies that changed with temperature and precursor type was demonstrated by morphological characterization using scanning electron microscopy and transmission electron microscopy. Cubic, rod-shaped, and nearly spherical-shaped PbS were formed. Powder X-ray diffraction (p-XRD) structural studies revealed the face-centered cubic structure of PbS nanoparticles. The elements contained in the nanoparticles were identified by energy dispersive X-ray spectroscopy (EDX). These results suggest that the size, shape, and optical properties of the synthesized PbS NPs were affected by reaction temperature, capping group, and precursor type. Under UV irradiation, the photocatalytic activity of HDA-capped PbS nanoparticles on the degradation of methylene blue dye ranged from 28.3% to 60.0%, with lead sulfide nanoparticle obtained by thermolysis of complex (1) at 230°C showing the highest photocatalytic efficiency (60.0%).

Fe3 C/Fe Decorated N-doped Carbon Derived from Tetrabutylammonium tetrachloroferrate Complex as Bifunctional Electrocatalysts for ORR, OER and Zn-Air Batteries in Alkaline Medium.

The emergence of non-precious metal-based robust and economic bifunctional oxygen electrocatalysts for both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is crucial for the rational design of commercial rechargeable Zn-air batteries (RZAB) with safe energy conversion and storage systems. Herein, a facile strategy to fabricate a cost-efficient, bifunctional oxygen electrocatalyst Fe3 C/Fe decorated N doped carbon (FeC-700, the catalyst prepared at carbinization temperature of 700 °C) with a unique structure has been developed by carbonization of a single source precursor, tetrabutylammonium tetrachloroferrate(III) complex. The ORR and OER activity revealed excellent performance (ΔE=0.77 V) of the FeC-700 electrocatalyst, comparable to commercial Pt/C and RuO2, respectively. The designed temperature-tuneable structure provided sufficiently accessible active sites for the continuous passage of electrons by shortening the mass transfer pathway, leading to extremely durable electrocatalysts with high ECSA and amazing charge transfer performance. Remarkably, the assembled Zn-air batteries with the FeC-700 catalyst as the bifunctional air electrode delivers gratifying charging-discharging ability with an impressive power density of 134 mW cm-2 with a long lifespan, demonstrating prodigious possibilities for practical application.