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The oxygen evolution reaction (OER) is crucial for sustainable hydrogen production through competitive water electrocatalysis. In this work, nanostructured nickel (Ni) thin films deposited on porous nickel foam (NF) substrate are investigated for improved OER catalysis in alkaline medium. The time-dependent fabrication of Ni thin films is achieved via aerosol-assisted chemical vapor deposition (AACVD), which has shown promising impact on the OER performance. Particularly, the nanoscale Ni@NF electrocatalyst after 60-min of deposition showed outstanding OER properties including minimum overpotential of 285 and 423 mV to reach the current decade (10 mAcm−2) and even higher than 1000 mA/cm2, respectively. The electrode exhibits a small Tafel slope with a value of 70 mV dec−1, a higher TOF, a large electrochemically active surface area, better charge transport performance, and long-term stability over 20 h of continuous operation without significant loss. This OER catalytic activity for pristine Ni electrocatalysts is a significant milestone and is found much better than the benchmark noble metal OER catalysts as well as many other well-known 3D transition metal catalysts. The impressive OER performance is attributed to the synergic effect generated between nanostructured-Ni and porous NF substrate, which enhances the electrical conductivity of the designed catalysts. The low manufacturing cost, robustness, and durability make this catalyst viable in solar energy conversion and storage applications. • Single-step chemical vapor deposition of nickel thin film on porous nickel foam. • Changing deposition time affects thin film microstructure. • Investigation of nickel electrocatalyst for water oxidation in alkaline medium. • Nickel film fabricated for 60 min exhibits remarkable oxidation activity. • Nickel film electrocatalyst remains highly stable during electrochemical operation. [ABSTRACT FROM AUTHOR]

Slow kinetics and emotive design of electrocatalysts are the main barriers to effective oxygen evolution and hydrogen production from water. To overcome these challenges, nickel sulfide impregnated electrocatalysts with auxiliary structural features have recently attracted attention as effective alternatives for the oxygen evolution reaction (OER). Herein, nickel sulfide (NiS) nanowires are developed directly on nickel foam (NF), which have proven to be a highly efficient electrocatalyst for OER in an alkaline medium. For this, NiS nanowires were grown on NF for short intervals of 30, 60, 90 and 120 min through an aerosol-assisted chemical vapor deposition (AACVD) process using nickel diethyldithiocarbamate as a precursor. The as-developed NiS electrode showed excellent OER activity in 1.0 M KOH solution. It is noteworthy that the NiS electrode produced after 90 min provides a reference current density of 10 mA cm−2 at an overpotential (η) of 210 mV and achieves a higher current density of 500 mA cm−2 at an overpotential of 340 mV. Moreover, the nanocatalyst has observed a low Tafel value (60 mV dec−1) and good OER stability. After the electrolysis, it was found that the surface of the NiS catalyst was partially modified into nickel oxide. The S atom in the NiS catalyst can provide an activator function that first converts the sulfide to a hydroxide and then eventually becomes an oxyhydroxide species. The more active nickel hydroxide/oxyhydroxide phase raises the water oxidation performance to a new level. The facile synthesis of NiS nanowire films by AACVD tends to be used as an anodic material in various other power generation and energy conversion devices such as batteries, fuel cells, and supercapacitors. [Display omitted] • Time dependent fabrication of NiS via aerosol assisted chemical vapor deposition. • NiS-90 min variant exhibited remarkable oxygen evolution reaction (OER) activity. • Partial transformation NiS into more active NiO was responsible for efficient OER. [ABSTRACT FROM AUTHOR]

The fabrication of smart, efficient, and innovative devices critically needs highly refined thin‐film nanomaterials; therefore, facile, scalable, and economical methods of thin films production are highly sought‐after for the sustainable growth of the hi‐tech industry. The chemical vapor deposition (CVD) technique is widely implemented at the industrial level due to its versatile features. However, common issues with a precursor, such as reduced volatility and thermal stability, restrict the use of CVD to produce novel and unique materials. A modified CVD approach, named aerosol‐assisted CVD (AACVD), has been the center of attention due to its remarkable tendency to fabricate uniform, homogenous, and distinct nano‐architecture thin films in an uncomplicated and straightforward manner. Above all, AACVD can utilize any custom‐made or commercially available precursors, which can be transformed into a transparent solution in a common organic solvent; thus, a vast array of compounds can be used for the formation of nanomaterial thin films. This review article highlights the importance of AACVD in fabricating heterobimetallic oxide thin films and their potential in making energy production (e. g., photoelectrochemical water splitting), energy storage (e. g., supercapacitors), and environmental protection (e. g., electrochemical sensors) devices. A heterobimetallic oxide system involves two metallic species either in a composite, solid solution, or metal‐doped metal oxides. Moreover, the AACVD tunable parameters, such as temperature, deposition time, and precursor, which drastically affect thin films microstructure and their performance in device applications, are also discussed. Lastly, the key challenges and issues of scaling up AACVD to the industrial level and processing for emerging functional materials are also highlighted. [ABSTRACT FROM AUTHOR]

Trimetallic cobalt-nickel-vanadium oxide (CoNiVO x) thin films were fabricated on aerospace grade AA2024 Al alloy specimens to investigate their behavior as anticorrosion coatings in a sodium chloride (NaCl) medium. Compact and homogenous nanostructured CoNiVO x coatings were developed using aerosol-assisted chemical vapor deposition by varying the deposition duration from 45 to 150 min at a constant temperature (475 °C). The structure and composition of the trimetallic CoNiVO x thin films were comprehensively investigated using X-ray diffraction, transmission electron microscopy, scanning electron microscopy/energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy, which demonstrated the successful synthesis of CoO/NiO/VO composite materials. The electrochemical corrosion properties of the trimetallic CoNiVO x films in a 3.5 % NaCl solution were determined using Tafel extrapolation and impedance spectroscopic tests, whereas the electrochemical stability and localized corrosion characteristics were determined using scanning electrochemical microscopic analyses. This study demonstrates that the trimetallic CoNiVO x oxide layer fabricated for 150 min exhibited an effective barrier protection performance on Al surfaces against corrosive attack in NaCl media. [Display omitted] • CoNiVOx thin films were prepared on Al alloy with the different deposition time. • Surface analyses revealed the dense and crack free nanostructured thin films. • TEM results confirmed the polycrystalline CoNiVOx films with nano-crystallites. • Corrosion results validated the enhanced barrier performance of CoNiVOx films. • Electrochemical stability of CoNiVOx films was confirmed by the SECM results. [ABSTRACT FROM AUTHOR]

The surface of implant materials is one of the most significant factors for controlling the interaction between biomaterials and bone tissues. Hence, enhancing the clinical performance of bio-implants is being widely focused worldwide. Herein, we report that nanostructured silver (Ag) coatings prepared on medical grade 316L stainless steel (SS) substrates are promising implant/surgical materials for orthopedic applications. Homogeneous nanoparticle-shaped silver thin films as a function of growth time (15 to 60 minutes) were developed at a temperature of 450 °C through aerosol-assisted chemical vapor deposition (AACVD) using a silver (I) acetate solution. All silver films were characterized using various surface and structural analysis techniques to confirm the phase and stoichiometric purity of the coating. Scanning electrochemical microscopy experiments were conducted to inspect the initial degradation of silver films on 316L SS substrates in simulated body fluid (SBF). Corrosion assessments in the SBF medium indicated that all the coated 316L SS substrates under study exhibited higher corrosion resistance than the uncoated ones; in particular, Ag films grown in 30 minutes showed the highest corrosion resistance among the other silver coatings produced under different conditions. The better corrosion performance of the Ag-30 sample was attributed to the dense, compact silver layer obtained in 30 minutes of deposition utilizing the AACVD technique. [ABSTRACT FROM AUTHOR]

While the noble metals (e.g., platinum, (Pt)) remain the benchmark electrocatalyst for the hydrogen evolution reaction (HER), their mass production require a reduced metal loading and faster fabrication protocols. The aim of the present work is to prepare Pt thin films by simple and fast fabrication technique, and to evaluate their performance for HER. The thin films of Pt are grown on two substrates, namely titanium foil (Ti) and nickel foam (NF), using a single step aerosol assisted chemical vapor deposition (AACVD) method. The film deposition time are varied from 20 to 60 min. Microscopic analyses suggest a gradual evolution of the films into percolated and/or porous nanostructures, a feature that remains highly desired to allow the maximum access of active sites. The performance of the as-prepared electrodes is evaluated by monitoring the HER in acidic electrolyte. The Pt film on nickel foam (Pt/NF) exhibits better electrical conductivity and smaller charge transfer resistance, while the film deposited on the Ti foil (Pt/Ti) demonstrates superior catalytic activity per active sites. The as-prepared Pt/Ti and Pt/NF electrodes produce 10 mA cm−2 at overpotential of 28 mV and 26 mV, respectively, better in performance than commercial Pt/C electrode (~39 mV), set a new bench mark electrocatalyst for the HER. Platinum electrodes prepared on metallic substrates by aerosol-assisted chemical vapor deposition approach exhibit outstanding HER performance. Image 1 • Deposition of Pt thin films through aerosol assisted chemical vapor deposition. • Effect of deposition time and substrate on microstructure of Pt thin films. • Evaluation of Pt electrocatalyst for hydrogen evolution reaction (HER). • Pt electrode prepared in 20 min performed better than the benchmark Pt/C. [ABSTRACT FROM AUTHOR]

The aim of the present study is to produce high performance Pd-based electrodes for water splitting by a simple and fast preparation technique, and to investigate the impact of substrates and film growth time on electrode performance. The electrodes are prepared in one step by the aerosol-assisted chemical vapor deposition (AACVD) method within 30 to 120 min. Pd is deposited on titanium (Ti) foil and nickel foam (NF). Microscopic analyses indicate the growth of cauliflower-like porous nanostructures of Pd. Electrochemical measurements indicate that the Pd/NF electrode requires only 65 mV and 189 mV, while the Pd/Ti electrode requires 121 mV and 288 mV to produce current densities of 50 and 150 mA cm−2, respectively, for the hydrogen evolution reaction (HER). The respective Tafel slopes for Pd/NF and Pt/Ti are determined to be 29.3 mV dec−1 and 52.3 mV dec−1, suggesting different rate-determining mechanisms of the HER on various substrate surfaces. The better activity of the Pd/NF electrode is attributed to higher electrical conductivity of bare NF and Pd/NF electrodes compared to that of bare Ti and Pd/Ti electrodes, though the charge transfer resistances are discerned to be comparable. The turnover frequency of the Pd/NF electrode is superior to that of Pd/Ti at lower overpotential, which becomes comparable with increasing potential. The results of this study combined with our earlier findings reveal the bi-functional electrocatalytic nature of the nanoscale Pd for possible utilization in an electrochemical water splitting unit for H2 and O2 production. [ABSTRACT FROM AUTHOR]

In this work, a selective dopamine (DA) sensor has been constructed based on thin film (TF) palladium nanoparticles (PdNPs) fabricated over indium tin oxide (ITO) (TFPdNP_ITO) by aerosol assisted chemical vapor deposition (AACVD) method. The TFPdNP_ITO electrodes were characterized with SEM, XRD, EDX, XPS, cyclic voltammetry (CV), tafel plot analysis, and electrochemical impedance spectroscopy (EIS). We performed geometry optimization of metallic planes, and Monte Carlo Search (MCS) computational simulations of DA, and interfering species to understand the effects of PdNPs on the selective DA detection at the atomic level. The total energy, and bind energy calculations from geometry optimizations showed that DA had the most negative energy value, and was most likely to interact with the TF of PdNPs. The adsorption locator module also predicted similar results through MCSs. A possible reaction mechanism for the DA oxidation at the TFPdNP_ITO was predicted based on the experimental and computational findings. The amperometry analysis showed linear range, sensitivity, and LOD of 1.77 μM – 543 μM, 0.009 μA/μM, and 0.13 ± 0.06 μM, respectively. The TFPdNP_ITO sensor was further tested for stability, and reproducibility. Commercial dopamine hydrochloride injection (DAHI) was used for the real sample analysis using both DPV, and amperometry techniques. [ABSTRACT FROM AUTHOR]

Newly synthesized dithiocarbamate precursors of platinum are used in a facile one-step AACVD procedure to fabricate pure phase platinum thin films of deposition time dependent structural and dimensional attributes. These films have shown higher efficiency as counter electrodes in dye sensitized solar cells as compared to the configurations using platinum electrodes made via doctor blade's method. A facile and cost effective AACVD procedure for the synthesis of platinum thin films has been reported using newly synthesized Pt-dialkyldithiocarbamate complexes, [Pt(S 2 CNR 2)] (where R = isobutyl, i Bu (1); benzyl, Bz (2)), as single source precursors. The structural characterization of the dithiocarbamate complexes has been performed by single crystal X-ray diffraction, 1H and 13C NMR, FT-IR and thermogravimetric analysis. The structure, composition, and morphology of the resulting Pt-films is established through XRD, XPS, EDX and FE-SEM analyses. The catalytic performance of the as-synthesized Pt-films is evaluated by using them as counter electrodes in dye sensitized solar cells as an example application. The efficiency of the AACVD produced electrodes is found to be better than conventionally used Pt-counter electrodes made from the doctor blade's method. It is also demonstrated that films having a well-connected and defect free surface topography show better catalytic performance, which is due to their high conductivity and reflectivity. Thus a simple and low cost method employing dithiocarbamate precursors is manifested to be immensely efficient in generating Pt-films and electrodes of tremendous applicability. [ABSTRACT FROM AUTHOR]

CaTiO3-TiO2 composite oxide films have been employed, for the first time, as photoelectrodes in photoelectrochemical (PEC) splitting of water. The transparent methanol solutions of Ti(iPro)4 and newly synthesized calcium complex [Ca2(TFA)3(OAc)(iPrOH)(H2O)(THF)3] (1) (where TFA stands for trifluoroacetato; OAc stands for acetate; and iPrOH stands for isopropanol) were utilized for aerosol assisted chemical vapor deposition (AACVD) of the target films. The composite electrodes were deposited on fluorine doped tin oxide (FTO) coated conducting glass substrates at varying deposition temperatures of 500-600 °C. The resulting films were extensively characterized by powder X-ray diffraction, X-ray photoelectron spectroscopy, energy dispersive X-ray analysis and scanning electron microscopy. PEC responses of all the composite electrodes were studied under simulated solar irradiation of AM 1.5 G (100 mW cm−2). The CaTiO3-TiO2 photoanode formed at 600 °C showed higher photocurrent density of 610 µA cm−2 at 0.7 V versus Ag/AgCl/3 M KCl reference electrode as compared to the other two electrodes fabricated similarly with only difference of fabrication temperature (i.e., 500 and 550 °C). [ABSTRACT FROM AUTHOR]

A homogeneous 1 : 1 solution of tetraisopropoxytitanium(iv) and [Sn(OAc)(dmae)]2 precursors in toluene was used at 450 °C, under argon, to deposit p–n-type tin(ii) oxide–titanium(iv) oxide nanocomposite thin film electrodes by a single step aerosol assisted chemical vapor deposition (AACVD) technique. Field emission scanning electron microscopy (FESEM), X-ray diffractometry (XRD), Raman scattering, energy-dispersive X-ray spectrometry (EDX), X-ray photoelectron spectroscopy (XPS) and UV-vis absorption spectrophotometry were conducted to characterize the thin film electrodes. The deposited thin film electrodes were tested for their applications in water photolysis. A comparison of the photoelectrochemical properties of the deposited SnO–TiO2 composite electrodes with those of pristine TiO2 and SnO electrodes fabricated from tetraisopropoxytitanium(iv) and [Sn(OAc)(dmae)]2, respectively, indicates a higher photocatalytic activity as compared to pristine TiO2. This is possibly due to the incorporation of p-type SnO, which effectively promoted the separation of photogenerated charge carriers to rectify electron transfer from SnO to TiO2, leading to the separation of electron–hole pairs. The combined synergistic effect of p-type SnO and n-type TiO2, flower-like morphology and augmented ability to absorb solar light produced a significantly enhanced photocurrent of ∼4.3 mA cm−2 at 0.7 V vs. Ag/AgCl electrode. No obvious photocurrent decay was noted for prolonged stability measurements of up to 60 min under one sun illumination of 100 mW cm−2. With such a facile synthetic strategy and enhanced performance profile, the resulting material provides inspiration for producing new p–n-type composite photoanodes for better PEC performance using similar strategies. [ABSTRACT FROM AUTHOR]

Present work demonstrates the synthesis of a novel heterobimetallic complex [Mg 2 TiO(TFA) 6 (THF) 2 (H 2 O)] ( 1 ) (where TFA = trifluoroacetato and THF = tetrahydrofuran), formed from the chemical interaction of magnesium (II) acetate tetrahydrate with titanium (IV) isopropoxide and trifluoroacetic acid in THF solution. Complex ( 1 ) adequately characterized through attenuated total reflection infrared spectroscopy, single-crystal X-ray diffraction and thermogravimetric analysis was implemented as single source molecular precursor in the aerosol assisted chemical vapor deposition. The deposition of magnesium orthotitanate (Mg 2 TiO 4 ) ceramic films on fluorine doped tin oxide coated conducting glass substrate was observed at various temperatures of 500, 550 and 600 °C. Film characterization techniques including; X-ray powder diffraction, scanning electron microscopy, energy dispersive X-ray and X-ray photoelectron spectroscopy divulge the fabrication of phase pure spherical shaped Mg 2 TiO 4 architectures with precise stoichiometry and high purity. [ABSTRACT FROM AUTHOR]

Pristine Mn2O3 and Ag–Mn2O3 composite thin films have been developed on fluorine doped tin oxide (FTO) coated glass substrates at 450 °C by aerosol assisted chemical vapor deposition (AACVD) using a methanol solution of a 1 : 2 mixture of acetatoargentate(i), Ag(CH3COO), and a newly synthesized manganese complex, [Mn(dmae)2(TFA)4] (1) (dmae = N,N-dimethylaminoethanolate, TFA = trifluoroacetate). The phase purity and stoichiometric composition of the films were investigated by X-ray diffraction (XRD) and Raman spectroscopy techniques. Energy dispersive X-ray (EDX) and X-ray photoelectron spectroscopy (XPS) analyses revealed a Ag to Mn ratio of 1 : 2 and further confirmed the uniform dispersion of Ag nanoparticles into the Mn2O3 structure. Optical studies showed a direct band gap of 2.0 eV for the pristine Mn2O3 film that was lowered to 1.8 eV for Ag–Mn2O3 due to the plasmonic interaction of Ag with Mn2O3. The Ag–Mn2O3 composite film displayed enhanced photocatalytic activity in photoelectrochemical (PEC) water splitting and yielded a photocurrent of 3 mA cm−2 at 0.7 V versus Ag/AgCl which was 1.6 times higher than a pristine Mn2O3 film alone, under AM 1.5 G illumination (100 mW cm−2). The high PEC efficiency is mainly due to the plasmonic effect of Ag nanoparticles, which enhances the visible light absorption, efficient electron–hole separation and high carrier mobility of the Ag–Mn2O3 photoelectrode. The charge carrier density of Ag–Mn2O3 is two times higher than the pristine Mn2O3 as calculated by the Mott–Schottky plot. Based on the PEC studies a mechanism is proposed to elucidate the high activity of Ag–Mn2O3 in PEC water splitting. [ABSTRACT FROM AUTHOR]

Electrolytic water splitting is promising strategy for the production of Green Hydrogen (H 2) but the sluggish kinetics during the oxygen evolution reaction (OER) is still a challenge. Herein, nickel palladium (NiPd) electrocatalyst has been presented for energy-efficient water oxidation. The catalyst films have been deposited on nickel foam (NF) substrate using a single-step aerosol-assisted chemical vapor deposition technique. The thickness of the deposited film is controlled by varying the deposition time from 60 to 180 min. The morphology and structure of the NiPd catalysts were characterized and directly employed for OER investigation in 1.0 M KOH. The catalyst made for 120 min initiates OER at an extremely low onset potential of 1.4 V vs. RHE (η = 170 mV), requires an overpotential of just 180 mV to approach the benchmark current density of 10 mA cm-2 and peak current density of > 1300 mA cm-2 is achieved at an overpotential of mere 370 mV. Moreover, the catalyst demonstrates excellent durability during prolonged water electrolysis experiments and imposing kinetics for OER. The catalytic performance of NiPd electrode is many folds better than the star catalyst (IrO 2) investigated under similar circumstances. The superior OER activity of NiPd alloy at such low overpotentials is accredited to the mutual relevance of high electroactive sites at intermetallic catalyst surface, the favorable synergy created between intrinsically active 3d-transition metal Ni and noble metal, Pd grown over porous and conductive NF surface that cumulatively favors electronic communications and adsorption/desorption process at nano surfaces of the catalytic film. [Display omitted] • Single step time dependent deposition of NiPd alloy catalyst on nickel foam. • NiPd electrode exhibit outstanding electrochemical oxygen evolution reaction. • Catalytic study demonstrates low over potential and highly stable nature of NiPd. [ABSTRACT FROM AUTHOR]

Symmetrical and unsymmetrical dithiocarbamato pyridine solvated and non-solvated complexes of indium(iii) with the general formula [In(S2CNRR′)3]·n(py) [where py = pyridine; R,R′ = Cy, n = 2 (1); R,R′ = iPr, n = 1.5 (2); NRR′ = Pip, n = 0.5 (3) and R = Bz, R′ = Me, n = 0 (4)] have been synthesized. The compositions, structures and properties of these complexes have been studied by means of microanalysis, IR and 1H-NMR spectroscopy, X-ray single crystal and thermogravimetric (TG/DTG) analyses. The applicability of these complexes as single source precursors (SSPs) for the deposition of β-In2S3 thin films on fluorine-doped SnO2 (FTO) coated conducting glass substrates by aerosol-assisted chemical vapour deposition (AACVD) at temperatures of 300, 350 and 400 °C is studied. All films have been characterized by powder X-ray diffraction (PXRD) and energy dispersive X-ray analysis (EDX) for the detection of phase and stoichiometry of the deposit. Scanning electron microscopy (SEM) studies reveal that precursors (1)–(4), irrespective of different metal ligand design, generate comparable morphologies of β-In2S3 thin films at different temperatures. Direct band gap energies of 2.2 eV have been estimated from the UV-vis spectroscopy for the β-In2S3 films fabricated from precursors (1) and (4). The photoelectrochemical (PEC) properties of β-In2S3 were confirmed by recording the current–voltage plots under light and dark conditions. The plots showed anodic photocurrent densities of 1.25 and 0.65 mA cm−2 at 0.23 V vs. Ag/AgCl for the β-In2S3 films made at 400 and 350 °C from the precursors (1) and (4), respectively. The photoelectrochemical performance indicates that the newly synthesised precursors are highly useful in fabricating β-In2S3 electrodes for solar energy harvesting and optoelectronic application. [ABSTRACT FROM AUTHOR]

Zinc sulphide (ZnS) thin films have been deposited on fluorine-doped tin oxide-coated conducting glass substrates at 375, 425 and 475°C temperatures from single source adduct precursors [Zn(S2CNCy2)2(py)] (1) [where, Cy=cyclohexyl, py=pyridine] and [Zn{S2CN(CH2Ph)(Me)}2(py)] (2) [where, Ph=Phenyl, Me=Methyl] using aerosol assisted chemical vapour deposition (AACVD). The precursor complexes have been characterized by microanalysis, infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, X-ray single crystal and thermogravimetric analysis. Thermal analysis showed that both precursors (1) and (2) undergo thermal decomposition at 375°C to produce ZnS residues. The deposited ZnS films have been characterized by X-ray diffraction and energy dispersive X-ray spectroscopy. Scanning electron microscopic studies indicated that the surface morphology of ZnS films strongly depends on the nature of the precursor and the deposition temperature, regardless of marginal variation in thermal stability of the precursors. Direct band gap energies of 3.36 and 3.40eV have been estimated from the ultraviolet–visible spectroscopy for the ZnS films fabricated from precursors (1) and (2), respectively. The current–voltage characteristics recorded under air mass 1.5 illumination confirmed that the deposited ZnS thin films are photoactive under anodic bias conditions. Furthermore, the photoelectrochemical (PEC) results indicate that these synthesised single source precursors are suitable for obtaining ZnS thin films by AACVD method. The ZnS thin film electrode prepared in this study are very promising for solar energy conversion and optoelectronic applications. The PEC properties of ZnS electrodes prepared from (2) are superior to that of the ZnS electrode prepared from precursor (1). [ABSTRACT FROM AUTHOR]

Abstract: A heterobimetallic single molecular precursor, [Fe2Ti4(μ-O)6(TFA)8(THF)6] (1) [TFA=trifluoroacetate, THF=tetrahydrofuran], was synthesized by the simple reaction of [Fe3O(OAc)6(H2O)3]NO3·4H2O [OAc=acetato] with tetrakis(2-ethoxyethanalato)titanium(IV) in the presence of trifluoroacetic acid in THF. The synthesized precursor was analyzed by melting point, CHN analysis, FTIR, single crystal X-ray diffraction and thermogravimetric analysis. Complex (1) crystallizes in the orthorhombic space group Pca21 with cell dimensions a =19.2114(14), b =20.4804(15) and c =17.2504(12)Å, and the complex undergoes thermal decomposition at 490°C to give a residual mass corresponding to an Fe2TiO5–TiO2 composite mixture. The synthesized precursor was utilized for deposition of Fe2TiO5–TiO2 composite thin films by aerosol-assisted chemical vapor deposition (AACVD) on glass substrates at 500°C using argon as the carrier gas. Scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and X-ray powder diffraction (XRD) analyses of the thin films suggest the formation of good quality crystalline thin films of an Fe2TiO5–TiO2 composite with an average grain size of 0.105–0.120μm. [Copyright &y& Elsevier]

This research endeavor aimed to synthesize the lead (II) diphenyldiselenophosphinate complex and its use to obtain lead selenide nanostructured depositions and further the impedance spectroscopic analysis of these obtained PbSe nanostructures, to determine their roles in the electronics industry. The aerosol-assisted chemical vapor deposition technique was used to provide lead selenide deposition by decomposition of the complex at different temperatures using the glass substrates. The obtained films were revealed to be a pure cubic phase PbSe, as confirmed by X-ray diffraction analysis. SEM and TEM micrographs demonstrated three-dimensionally grown interlocked or aggregated nanocubes of the obtained PbSe. Characteristic dielectric measurements and the impedance spectroscopy analysis at room temperature were executed to evaluate PbSe properties over the frequency range of 100 Hz–5 MHz. The dielectric constant and dielectric loss gave similar trends, along with altering frequency, which was well explained by the Koops theory and Maxwell–Wagner theory. The effective short-range translational carrier hopping gave rise to an overdue remarkable increase in ac conductivity (σac) on the frequency increase. Fitting of a complex impedance plot was carried out with an equivalent circuit model (Rg Cg) (Rgb Qgb Cgb), which proved that grains, as well as grain boundaries, are responsible for the relaxation processes. The asymmetric depressed semicircle with the center lower to the impedance real axis provided a clear explanation of non-Debye dielectric behavior. [ABSTRACT FROM AUTHOR]

Herein, thin NiPd nanoalloy thin films were coated on 316L stainless steel (SS) substrates by aerosol-assisted chemical vapor deposition (AACVD) to investigate their capability to protect the SS surface against corrosion in a marine environment. The nanoalloy films were coated at various thicknesses (1–2 μm) by changing the deposition time from 1 to 3 h using a precursor solution consisting of nickel(II) acetylacetonate and palladium(II) acetylacetonate. Analyses by X-ray diffraction, scanning electron microscopy/energy-dispersive X-ray spectrometry, and X-ray photoelectron spectroscopy confirmed the successful formation of clustered crystalline nanoparticles of NiPd alloy films with high phase purity and controlled thickness on steel substrates. The surface protection performance of the deposited films against corrosion in a 3.5% NaCl electrolyte was studied by potentiodynamic polarization and electrochemical impedance spectroscopic analyses, while the localized corrosion features were examined by the scanning vibrating electrode technique. These analyses suggested that the NiPd alloy film formed at a deposition time of 2 h exhibits excellent barrier protection performance against corrosion in the NaCl solution. Thus, the NiPd nanoalloy film formed by the facile, rapid, and cost-effective AACVD route is a highly promising protective coating for SS against the corrosive marine environment. [Display omitted] • Development of NiPd alloy coatings on 316L SS substrate by AACVD • Electrochemical investigation of NiPd as surface protective layers in NaCl • NiPd coated SS showed excellent corrosion performance in marine environment. [ABSTRACT FROM AUTHOR]

This research aims to synthesize the Bis(di-isobutyldithiophosphinato) nickel (II) complex [Ni(iBu2PS2)] to be employed as a substrate for the deposition of nickel sulfide nanostructures, and to investigate its dielectric and impedance characteristics for applications in the electronic industry. Various analytical tools including elemental analysis, mass spectrometry, IR, and TGA were also used to further confirm the successful synthesis of the precursor. NiS nanostructures were grown on the glass substrates by employing an aerosol assisted chemical vapor deposition (AACVD) technique via successful decomposition of the synthesized complex under variable temperature conditions. XRD, SEM, TEM, and EDX methods were well applied to examine resultant nanostructures. Dielectric studies of NiS were carried out at room temperature within the 100 Hz to 5 MHz frequency range. Maxwell-Wagner model gave a complete explanation of the variation of dielectric properties along with frequency. The reason behind high dielectric constant values at low frequency was further endorsed by Koops phenomenological model. The efficient translational hopping and futile reorientation vibration caused the overdue exceptional drift of ac conductivity (σac) along with the rise in frequency. Two relaxation processes caused by grains and grain boundaries were identified from the fitting of a complex impedance plot with an equivalent circuit model (Rg Cg) (Rgb Qgb Cgb). Asymmetry and depression in the semicircle having center present lower than the impedance real axis gave solid justification of dielectric behavior that is non-Debye in nature. [ABSTRACT FROM AUTHOR]

Thin films of metallic rhodium (Rh) are developed on two different supports, nickel foam (NF) and titanium foil (Ti), and evaluated for electrochemical hydrogen evolution reaction (HER). The electrodes are prepared by aerosol-assisted chemical vapor deposition technique using a Rh diethyldithiocarabamte precursor for three distinct time periods of 40, 80, and 120 min at 500 °C. The film consists of phase pure metallic Rh with hierarchical flower-like morphology. The structural features of such nanostructures can be modulated by adjusting the growth time. The HER catalytic performance data for the optimized films (i.e., with the deposition time of 80 min) suggest that the Rh deposited on Ti foil (Rh/Ti) catalyze the reaction substantially faster than Rh deposited on Ni foam (Rh/NF). To produce current density of 100 mA cm−2, the Rh/NF needed over potential of 263 mV, while the Rh/Ti electrode required only 175 mV. In spite of lower electrical conductivity, caused by the bare Ti foil, the Rh/Ti electrode exhibits superior HER performance. The Tafel slopes of Rh/NF and Rh/Ti electrodes are determined to be 52 and 42 mV dec−1, while the turnover frequencies are estimated to be 1.1 and 37.3 s−1 at over potential of 260 mV. [ABSTRACT FROM AUTHOR]

Electrocatalytic oxygen evolution reaction (OER) is one of the most promising candidates for the sustainable energy. This has led researchers to focus towards developing highly active electrocatalysts. Our work takes a wholistic approach to understanding the key factors that influence the OER process. We focused on preparing a metallic electrocatalyst and tested out its OER performance using two different supporting electrolytes. We also studied the effect of crystal planes of the electrocatalyst on the OER process using computational simulation (CS) methods. For this, rhodium (Rh) thin film (RhTF) electrocatalysts on indium tin oxide (RhTF_ITO) were fabricated for OER through aerosol assisted chemical vapor deposition (AACVD). The prepared electrodes showed excellent electrocatalytic activity for OER (for 10 mA/cm2 η = 273 mV in 1.0 M KOH). The effect of the supporting electrolytes and the crystal planes of RhTF electrodes were analyzed using electroanalytical techniques and CS methods. Tafel slope (TS) analysis revealed that electron transfer kinetics was slower for the NaOH compared to the KOH. The scan rate (ν) analysis indicated that there is weak electrostatic interaction between the hydrated outer Helmholtz plane (OHP) of Na+ and K+ ions with the adsorbed OH (ad) that impacts the OER process. With increasing ν the restructuring of the electrochemical double layer (EDL) increases resulting in similar OER performance for both the supporting electrolytes. The micro-kinetic analysis showed that the rate determining step (RDS) for NaOH and KOH required around 1.67 eV and 1.07 eV. The density functional theory (DFT) analysis revealed that these energy values are closest to the Rh (111) plane reaction pathway. Adsorption locator (AL) analysis further revealed that the hydrated cations could directly get adsorbed on the Rh crystal planes hindering the electron transfer (ET) in the OER process. The DFT analysis further revealed that the lowest energy pathway for the OER process is followed on the Rh (220) plane. These analyses demonstrated that it is possible to fine tune the OER using supporting electrolyte and electrocatalysts that can work synergistically for getting the optimal OER performance. [Display omitted] • Synthesis of seaweed like metallic Rh TF through AACVD method. • Supporting electrolyte significantly impacts OER performance of electrocatalysts. • The hydrated cations (K+ and Na+) are responsible for this difference in OER performance. • The Rh (220) crystal plane shows the lowest energy pathway for the OER process. • The total energy of the crystal planes determine how they would interact with the hydrated cations. [ABSTRACT FROM AUTHOR]