Sulfurization Temperature Research Articles

Growth and Characterization of CZTS Thin Films Synthetized by Electrodeposition Method for Photovoltaic Applications

In the present work we deposited CZTS absorber material using a one-step electrodeposition method on ITO glass substrates. We studied the effect of sulfurization temperature on structural, morphological and optical properties of CZTS thin films sulfurized in N2+H2S atmosphere at 350, 375, 400 and 425°C for 10 min respectively for 10 min. The films have been charaterized by different techniques including X-ray diffractometer (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and UV-visible-NIR spectrophotometer. XRD patterns indicated kesterite CZTS with preferential orientation along (112) plane, the intensity of peaks increased with increase of sulfurization temperature signified the amelioration of the crystallinity with sulfurization temperature increased, the estimated crystallite size are in the range of 14.27-37.32 nm. Raman scattering experiments confirmed the presence of CZTS thin films by the characteristic peak at 336 cm−1. SEM images showed the morphology of CZTS thin films improved with increasing of sulfurization temperature. UV-Visible-NIR spectrophotometer showed that the values of optical absorption coefficient are larger than 104 cm−1 and optical band gap energy of CZTS thin films decreased with increasing of sulfurization temperature ranging 1.56 and 1.66 eV. These results make the electrodeposited CZTS films a suitable material as absorber material in solar cells applications based thin films.

A Sustainable Approach for Producing Ti and TiS2 from TiC

TiC was examined as a starting material for Ti metal production by sulfidation and electrochemical reduction in molten salt. The sulfur evaporation temperature, sulfidation temperature, and time were optimized in a dual-zone furnace for the efficient and sustainable formation of TiS2 as well as carbon removal from TiC by S2 gas sulfidation. A mixture of TiS2 and Ti2.45S4 powders was synthesized from TiC at 1200 °C, and a perfect carbon removal was achieved to a very clean level as low as 0.025 mass pct C. The sulfides derived from TiC were then electrochemically reduced in molten CaCl2-0.5 mol pct CaS salt. The spherical shape Ti powder consisting of high-purity Ti sheets was obtained from TiS2 without the carbon contamination. This method might be applied for sustainable recycling of waste carbides and for production of low-cost Ti powders via TiC or TiOxCyNz from the titanium ore.

Elimination of dibenzothiophene from n-hexane by nano-composite membrane containing Cu-MOF in a pervaporation process

In this study, a particular type of thin film nano-composite membranes was prepared and used in the pervaporation process. The membranes were made of polyphenylsulfone and were coated with a thin layer of polydimethylsiloxane containing different amount of Cu-metal–organic framework (MOF) nano-structures. N-hexane containing dibenzothiophene was used as a model fuel. To characterize MOF and the prepared membranes, Fourier transform infrared, X-Ray diffraction, Brunauer–Emmett–Teller, field-emission scanning electron microscopy, water contact angle measurements, and thermogravimetric analysis were used. The effect of parameters such as sulfur content, process temperature, and Cu-MOF concentration on the membrane performance was evaluated. The results indicated that nano-composite membranes demonstrate a much better performance compared to the untreated membrane. The membrane containing 5 wt% Cu-MOF with a contact angle of 97° had more hydrophilic surface and proved the effect of the additive in improving the surface hydrophilicity. This membrane had the highest rate of flux and rejection (0.4 kg/m2 h and 70%, respectively), and the lowest enrichment factor (0.3). As the temperature increased, the flux of M4 membrane (with 5 wt% additive) increased, while the removal efficiency decreased significantly. The optimum temperature for desulfurization in the pervaporation process was obtained (50 °C).

A thin Cu interlayer-mediated control of phase evolution of Cu2ZnSnS4 thin films grown by RF magnetron sputtering of a single elementary target with high white light sensitivity

Although sputter deposition from a single target to prepare Cu2ZnSnS4 (CZTS) thin films appears attractive, it must suppress the growth of secondary phases that detrimentally affect performance of CZTS based thin film solar cells. Here we demonstrate a rational strategy for deposition of phase pure kesterite CZTS films by RF magnetron sputtering using a single target prepared from elemental powders via a thin Cu interlayer-mediated control of phase evolution. The films grown from a target of stoichiometric elemental proportion were Cu poor that determined the reaction pathway during sulfurization and resulted in growth of spurious phases despite a large variation in the sulfurization configuration. Inserting a 195 nm thick Cu interlayer between successively sputtered precursor layers provided improved compositional stability through thermally activated diffusion of Cu from the intermediate layer towards both the sides and resulted in the formation of kesterite CZTS even at a modest sulfurization temperature of 500 °C. The obtained phase-pure films have a bandgap of ~1.58 eV. The films show excellent photoresponse behavior characterized by increase in current by three orders of magnitude at a bias of 3 V upon white light illumination, typically that required for a potential absorber layer in thin film solar cells.

Impact of sulfurization parameters on properties of CZTS thin films grown using quaternary target

In this study, CZTS thin films were grown by annealing of sputtered films using quaternary single target employing various annealing parameters. The effects of the post-sulfurization treatment, reaction temperature (500, 525, 550 and 575 °C) and sulfurization time (60, 90, 120 and 150 s) on the properties of CZTS thin films were analyzed. The optimization of reaction temperature for 60 s dwell time was examined by annealing the precursor films with/without sulfur atmosphere. It was shown that annealing of the films under the sulfur atmosphere prevents Zn-loss in the samples for higher annealing temperatures (550 and 575 °C) and hindering the formation of secondary phases such as Cu2−xS, Cu2SnS3 (CTS). The FWHM values of the sulfurized samples revealed that the sulfurization temperature of 550 °C is preferable for the fabrication of CZTS samples. Further optimization was performed at 550 °C for various sulfurization times. It was seen that all the samples have Cu-poor and Zn-rich composition. The XRD pattern of CZTS samples displayed formation of kesterite CZTS phase but SnS2 phase formations were also observed for longer sulfurization time (> 120 s). It was also observed that the sulfurization time has more significant contribution on the crystallite size of the samples with respect to sulfurization temperature. The Raman spectra of the CZTS samples confirmed the formation of kesterite structures for all the films and appearance of secondary phase for films prepared using longer sulfurization time (> 120 s). All the samples displayed a dense and polycrystalline surface morphology, but the sulfurized sample for 120 s displayed more homogenous and prominent morphology. The room temperature PL measurements demonstrated a broad band which peaked at about 1.36–1.37 eV, which is very close to the band gap of kesterite CZTS structure. The electrical characterization of the samples showed that all the samples have p-type conductivity and the CZTS-S-550-120 sample has a more promising result considering both resistivity and carrier concentration.

Brown spot in table grape Redglobe controlled in study with sulfur dioxide and temperature treatments

Brown spot is a postharvest disease of grapes caused byCladosporiumspecies in the San Joaquin Valley of California. It spreads during cold storage and transport, resulting in severe economic losses to late table grape cultivars, which are grown mainly for export to countries such as China and Mexico. We examined the effect of temperature and sulfur dioxide (SO2) treatments on fungal growth and infection of Redglobe berries by threeCladosporiumspecies:Cladosporium ramotenellum, C. cladosporioidesandC. limoniforme.Redglobe is especially popular for export. Fungal colonies growing on potato dextrose agar in petri plates stored at −2°C grew slower than those stored at 2°C, and an 400 ppm-h SO2treatment significantly reduced fungal growth of all three species and at all temperatures tested. Redglobe berries inoculated with theCladosporiumspecies, treated with SO2concentrations of 100 ppm-h, 200 ppm-h and 400 ppm-h and incubated in high relative humidity chambers for 28 to 32 days at 2°C, showed little incidence of disease. The development of brown spot on berries was entirely prevented with the treatment of 200 ppm-h SO2for allCladosporiumspecies tested.

The Effect of Deposition Time and Sulfurization Temperature on The Optical and Structural Properties of Iron Sulfide Thin Films Deposited from Acidic Chemical Baths

Pyrite phase FeS2 thin films have been grown by a two-stage process of chemical bath deposition followed by sulfurization. Thiourea and thioacetamide were used as sulfur precursors in separate baths. The deposition time was controlled for 1, 2, and 3 hours respectively. The as-deposited films were sulfurized at temperatures of 250 oC and 500 oC to form the pyrite phase. The effect of deposition time and sulfurization temperature on the structure, morphology and optical properties of the iron pyrite films obtained from the two separate baths were studied and compared. X-ray diffraction analyses established the formation of the pyrite phase in all the films after sulfurization, in addition to iron (II) oxide hydrate as impurities. All films showed further improvement in pyrite formation, crystallinity as well as an increase in crystallite size after sulfurizing at 500 oC. EDAX and SEM microscopy showed that the iron pyrite films produced from the bath containing thiourea, had better crystallinity and a higher iron content. The optical band gap of the iron pyrite films obtained with thiourea, was 2.1, 1.9 and 1.6 eV for the various deposition times. With thioacetamide, the band gap was 1.4 eV, for the deposition time of 3 hours.

Investigation of Zn/Sn ratio for improving the material quality of CZTS thin films with the reduction of Cu2-xS secondary phase

In this study, a sputtering system was adopted for the preparation of Cu2ZnSnS4 (CZTS) thin films with high material quality. The system precisely controlled the elemental ratio in a copper-zinc-tin (CZT) precursor for contributing to the grain growth of CZTS crystallites, and reduced the detrimental formation of the Cu2-xS secondary phase during the high-temperature sulfurization process.The CZT precursor was prepared in a layer sequence of Zn/Sn/Cu/Zn, as the Cu-capping layer could protect the underlying Zn/Sn bilayer from volatilization during the high-temperature sulfurization. The CZT precursors were subjected to the sulfurization process at varied temperatures ranging from 480 to 560 °C for 20 min to form the CZTS thin film. In this study, the Cu/(Zn + Sn) and Zn/Sn ratios in the CZTS film were studied by energy dispersive X-ray spectroscopy measurements, and both ratios revealed elevations with an increasing sulfurization temperature, owing to the thermal volatilization of Zn and Sn. Thus, the formation of the undesirable Cu2-xS secondary phase was enhanced, and the surface roughness and density of voids on the CZTS thin films were increased. For a reduced Zn/Sn ratio with a reduced sulfurization temperature, the improved CZTS thin-film quality was demonstrated by the increased X-ray diffraction (XRD) and Raman intensity, along with the reduction of the XRD linewidth of the (112) CZTS crystal phase. A CZTS thin film with a sulfurization condition of 500 °C for 20 min showed a low Zn/Sn ratio (at 1.1), along with the features of a dense and smooth thin-film surface. Moreover, a reduced photoluminescence spectra full width at half maximum (FWHM) value of 92.7 meV was observed.In addition, for further improving the grain growth of CZTS, a pre-annealing process of a CZT precursor was conducted at a temperature of 350 °C for 30 min. An enhancement of the CZTS crystallite size with the stoichiometric formation of a CZTS phase and a reduced Cu2-XS phase was observed, indicating the superior material quality of the CZTS thin films.

Structural and optical properties of In2S3 thin films deposited by sulfurization assisted thermal evaporation method

Indium sulfide (In 2 S 3 ) films were deposited onto soda lime glass by sulfurization assisted thermal evaporation method at different sulfurization temperatures. These films are further annealed for 1 hr at 300 °C. The structural, morphology and optical properties of these films are studied using x-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive x-ray analysis (EDAX), Raman and UV–Visible spectroscopy. Low angle-XRD analysis revealed that all films are polycrystalline in nature and confirmed the formation of only cubic phase of In 2 S 3 . The FE-SEM and EDAX analysis revealed significant change in the film morphology and composition upon sulfurization and annealing temperature. UV–Visible spectroscopy analysis showed that all films have strong absorption in visible region of the spectrum. With increase in sulfurization and annealing temperature the band gap increases and is found in the range 1.57–2.12 eV. However, band gap of In 2 S 3 thin films deposited at different sulfurization temperature are higher than those obtained after annealing of films.

Hierarchical Porous Integrated Co1−xS/CoFe2O4@rGO Nanoflowers Fabricated via Temperature‐Controlled In Situ Calcining Sulfurization of Multivariate CoFe‐MOF‐74@rGO for High‐Performance Supercapacitor

AbstractThe precise synthesis of electrode materials that integrate highly redox‐active transition‐metal oxide with conductive transition‐metal sulfide has always been a challenge, due to the extraordinarily robust coordination affinity of sulfur for transition metals. Herein, through controlling the calcined sulfurization temperature to stimulate the activity of oxygen to compete with sulfur, an integrated Co1−xS/CoFe2O4@rGO nanoflower is fabricated in the range of 780–830 °C by employing well‐designed Co0.8Fe0.2‐MOF‐74@rGO as precursor. The hierarchical‐pore structure evolved from the bimetallic MOF@rGO provides a suitable electrolyte environment to promote fast Faradaic reactions, which endows Co1−xS/CoFe2O4@rGO with a high specific capacity of 2202 F g−1 and remarkable cycling stability (90% after 20 000 cycles), superior to those of the most well‐known metal‐organic framework (MOF) derived systems. The assembled Co1−xS/CoFe2O4@rGO//AC asymmetric supercapacitor shows an outstanding energy density up to 61.5 Wh kg−1 at a power density of 700 W kg−1. A combined experimental and density functional theory calculation demonstrates that the merged Co1−xS/CoFe2O4 interface with optimized electronic structure facilitates electron transfer pathways and realizes the effective synergy of high redox activity from CoFe2O4 and good conductivity from Co1−xS, leading to the excellent electrochemical performance of the material. Additionally, the formation mechanisms of the temperature‐controlled different phases are systematically investigated.

Optical and electrical investigations on Cu2SnS3 layers prepared by two-stage process

Cu2SnS3 thin films were prepared using a simple and phase-controlled two-stage process. Initially, Cu-Sn precursors were deposited by DC sputtering, followed by sulfurization at different temperatures (Ts) that vary in the range, 150 - 500 °C. An exhaustive study of the optical properties in relation to sulfurization temperature was performed using transmission and reflectance measurements. The estimated optical absorption coefficient for all the layers was very high and found to be > 104 cm−1. The optical band gap was determined using Tauc plots and it varied in the range, 1.49–2.34 eV with an increase of Ts. The refractive index (n) and the extinction coefficient (k) were also obtained. The optical properties like dispersion parameters, dielectric constant, dissipation factor, optical conductivity, surface energy loss function, volume energy loss function and optical haze were also calculated. Further, analysis of electrical properties such as electrical resistivity, mobility and carrier density of the prepared films with sulfurization temperature was made in order to verify the suitability of synthesized CTS layers for solar cell application.

A comprehensive study on Cu2SnS3 prepared by sulfurization of Cu–Sn sputtered precursor for thin-film solar cell applications

In this work, a comprehensive study on the influences of the various synthesizing parameters of monoclinic Cu2SnS3 using the RF sputtering method, followed by the sulfurization process, is investigated. In particular, the impact of sputtering power and pressure on multi-material target Cu–Sn (compositional ratio Cu:Sn of 52:48%) was examined. All samples exhibited a monoclinic structure with similar split bandgaps around 0.9 eV. Increasing sputtering power showed direct effects on the sputtered Cu/Sn atoms ratio and the secondary phases obtained. The increase of sputtering pressure causes gas droplets and blistering on the film surfaces. The effects of changing the sulfurization temperature and the sulfur powder amount were also studied. The increase in the sulfurization temperature reduces the surface roughness, increases film crystallinity, and minimizes Cu-based secondary phases. The sulfur amount used during the sulfurization process showed a vital impact on film formation. Using a small amount of sulfur produced a partially sulfurized film that exhibited a poor performance solar cell. A power conversion efficiency of 1.94% is achieved with the optimized condition for the bare Cu2SnS3 without doping or heat treatment for the fabricated cell.

Effects of element ratio on robustness of CZTS films: Variations in sulfurization temperature

In this study, Cu2ZnSnS4 (CZTS) thin films are fabricated through radio frequency magnetron sputtering followed with sulfurization process under different annealing temperatures. Scanning electron microscopy, X-ray diffraction, energy dispersive X-rays, Raman spectroscopy, UV–vis–NIR spectroscopy, and Hall effect measurement system are used to characterize the fabricated CZTS films. Elemental ratio variations during the sulfurization process under different temperatures are examined from the perspective of the following decomposition process: Cu2ZnSnS4 (s) ⇋ Cu2S (s) + ZnS (s) + SnS (s) +1/2 S2 (s). Furthermore, the lattice parameters, grain size, full-width at half-maximum (FWHM), dislocation density, and micro-stress are calculated and analyzed in light of the elemental ratio variations. Meanwhile, the Raman spectra and a joint analysis with the energy band gaps validate the presence of secondary phases including orthorhombic Cu3SnS4, cubic Cu2SnS3 and tetragonal Cu2SnS3. The results indicate that the energy band gap can be adjusted by controlling the amount of S, loss of Sn through annealing temperature, and temperature of 500 °C is a appropriate sulfurization temperature for preventing the decomposition of CZTS during the annealing process. This study is an important reference for experimental works that seek to improve quality of CZTS thin films in solar cells with high conversion efficiency.

Three-phase trickle-bed reactor model for industrial hydrotreating processes: CFD and experimental verification

Catalytic hydrotreating (HDT) is a process used to remove impurities from refinery streams, reacting a given feed with hydrogen at high temperature and pressure in a trickle-bed reactor. In order to optimize the operation of such reactors, one needs information about the detailed performance of the reactor. However, mathematical models of such reactors have not received due attention in last decades. Therefore, this work aimed at revisiting a plug flow HDT model to predict the performance of industrial diesel hydrotreating reactor, which considers most of the HDT reactions, gas-liquid and liquid-solid mass transfer, as well as the influence of catalyst deactivation and quenches injection on model predictions. A fourteen pseudo-component reactional network was proposed and successfully used. Computational fluid dynamics (CFD) predictions verified the plug flow behavior of the industrial HDT reactor. Both the CFD and plug flow models were verified using real process plant data, inspecting residual sulfur content and temperature profiles, with maximum relative error of 14%. Pressure and species concentration profiles as well as the effect of inlet pressure and temperature on final sulfur content were predicted and discussed. Catalyst deactivation is an important factor for accurate prediction of industrial HDT over time of campaign.

Making Large‐Area Titanium Disulfide Films at Reduced Temperature by Balancing the Kinetics of Sulfurization and Roughening

AbstractThe synthesis of large‐area TiS2 thin films is reported at temperatures as low as 500 °C using a scalable two‐step method of metal film deposition followed by sulfurization in an H2S gas furnace. It is demonstrated that the lowest‐achievable sulfurization temperature depends strongly on the oxygen background during sulfurization. This dependence arises because TiO bonds present a substantial kinetic and thermodynamic barrier to TiS2 formation. Lowering the sulfurization temperature is important to make smooth films, and to enable integration of TiS2 and related transition metal dichalcogenides—including metastable phases and alloys—into device technology.

Low pressure sulfurization and characterization of multilayer MoS2 for potential applications in supercapacitors

The emergence of two-dimensional molybdenum disulfide (MoS2) has prompted enormous research attention as supercapacitor electrode materials due to their exciting electrochemical, electrical and mechanical properties. In this work, we present a low-pressure technique to grow multilayer MoS2 by sulfurization of molybdenum thin films at three different temperatures (700, 750 and 800 °C) to study the effect of growth temperatures on surface morphology, film thickness and film quality. Large area growth of MoS2 throughout the Si/SiO2 substrate was achieved at all the sulfurization temperature. The as-prepared MoS2 films were characterized by several techniques including X-ray diffraction, atomic force microscopy, scanning electron microscopy, Raman spectroscopy and photoluminescence spectroscopy. Although MoS2 is successfully grown at different temperatures, the surface morphology, thickness and crystallite size have varied significantly with temperature. Our results presented here will contribute towards the reproducible growth of large area MoS2 at the desired temperature for energy storage applications.

Controlled synthesis of nickel sulfide polymorphs: studies on the effect of morphology and crystal structure on OER performance

Herein, the Taguchi L-9 orthogonal technique has been employed to design the optimised conditions (sulfur source, temperature, reaction time and surfactant) for the preparation of nickel sulfide polymorphs using hydrothermal method. The experimental results demonstrate the temperature dependant phase transition of NiS → Ni3S4 → NiS2 and the prepared nickel sulfide polymorphs exhibit distinctive morphologies of sugar cubes, spherical apple, rose type, aggregated stones, and tubular bacteria type structures. The effect of morphology and crystalline structure on oxygen evolution reaction (OER) has been investigated for the first time where the OER performance follows the order: NiS > NiS2 > Ni3S4. Among the various morphologies of NiS, and NiS2, the order of OER performance is as follows: NiS(sugar-cubes) > NiS(agglomerated stone particles) > NiS(apple shaped) and NiS2(aggregated stoneparticles) > NiS2(rose type) > NiS2(tubular bacteria) shaped nanostructure.

Impact of low temperature sulfur exposure on the aging of small pore Cu-zeolite SCR catalyst

This study investigated the impact of low temperature sulfur exposure prior to hydrothermal aging on the catalytic structure and performance of Cu-SSZ-13 catalyst toward NH3-SCR reaction. The sulfur exposure temperature, duration and the sequence of sulfur exposure vs. hydrothermal aging are investigated. All samples hydrothermally aged in presence of SOx (SO3/SOx = 0.7) have showed decreased activity compared to the sample aged hydrothermally only, but the extent of deactivation varies with different sulfur exposure conditions. The sulfur exposure at 200 °C for 100 hours prior to HTA has the most pronounced impact on the population of active site (Cu) and the SCR performance at low temperatures. And the sample of equivalent thermal and sulfur exposure but with the HTA prior to the sulfur exposure, has less decreases in the active Cu sites and less sulfur stored. In contrast, sulfur exposure at high temperature, e.g. 650 °C, has the least impact on the Cu-SSZ-13 catalyst. The molar ratio of stored sulfur to the decrease amount of active Cu sites is close to 1:1 ratio, which implies the deactivation of sulfur exposed catalyst is mainly due to the decrease of active Cu population. Furthermore, DRIFTs demonstrated that both Z2Cu and ZCuOH sites decrease in most cases and ZCuOH is more impacted compared to Z2Cu. With these findings, we concluded that low temperature sulfur exposure prior to HTA treatment leads to accelerated aging. Further characterization reveals that the aging is mainly due to the decrease in the population of active Cu sites. The finding suggests that a hydrothermal pretreatment before sulfur exposure of Cu-SCR catalyst can retard the deactivation of catalyst to a limited extent in the real-world application.

Investigation on the sulfurization temperature dependent phase and defect formation of sequentially evaporated Cu-rich CZTS thin films

We report synthesis of Copper Zinc Tin Sulfide (CZTS) thin films using sequential evaporation technique. The as-deposited films were subjected to various sulfurization temperatures ranging from 520 °C to 640 °C. This paper presents a detailed analysis of temperature dependent phase and defect formation in Cu-rich off-stoichiometric CZTS thin films. CZTS thin films moved from F-type to C-type with decreasing Cu/Zn disorder and defect concentration with increasing sulfurization temperature. The resulting films showed less off-stoichiometry in contrast to initial choice of intended off-stoichiometry exhibiting the structural flexibility within the compositional limits. Despite being off-stoichiometric, all the samples exhibited the tetragonal CZTS phase with preferred orientations. Raman analysis showed the disappearance and reappearance of secondary phases with increasing sulfurization temperature. EDS analysis suggested that composition of the films moved towards better stoichiometry till 580 °C before deteriorating again. Composition and lattice parameter values suggested Cu-rich off-stoichiometric nature of sulfurized CZTS thin films. AFM study showed dependence of roughness with sulfurization temperature. Band gap was obtained in the range of 1.28 eV to 1.48 eV from UV–Vis spectroscopy measurement. PL analysis revealed the asymmetric shape and blue shift of the peaks. Band-to-tail recombination becomes pronounced with increase in sulfurization temperature. XPS analysis showed elements are in expected oxidation states.

Synthesis of a Hybrid Nanostructure of ZnO-Decorated MoS2 by Atomic Layer Deposition.

We introduce the synthesis of hybrid nanostructures comprised of ZnO nanocrystals (NCs) decorating nanosheets and nanowires (NWs) of MoS2 prepared by atomic layer deposition (ALD). The concentration, size, and surface-to-volume ratio of the ZnO NCs can be systematically engineered by controlling both the number of ZnO ALD cycles and the properties of the MoS2 substrates, which are prepared by sulfurizing ALD MoO3. Analysis of the chemical composition combined with electron microscopy and synchrotron X-ray techniques as a function of the number of ZnO ALD cycles, together with the results of quantum chemical calculations, help elucidate the ZnO growth mechanism and its dependence on the properties of the MoS2 substrate. The defect density and grain size of MoS2 nanosheets are controlled by the sulfurization temperature of ALD MoO3, and the ZnO NCs in turn nucleate selectively at defect sites on MoS2 surface and enlarge with increasing ALD cycle numbers. At higher ALD cycle numbers, the coalescence of ZnO NCs contributes to an increase in areal coverage and NC size. Additionally, the geometry of the hybrid structures can be tuned by changing the dimensionality of the MoS2, by employing vertical NWs of MoS2 as the substrate for ALD ZnO NCs, which leads to improvement of the relevant surface-to-volume ratio. Such materials are expected to find use in newly expanded applications, especially those such as sensors or photodevices based on a p-n heterojunction which relies on coupling transition-metal dichalcogenides with NCs.