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The switchback deposition strategy is a unique approach where the torch is moving cyclically forward and backward for preventing the unidirectional grain growth in wire + arc additive manufacturing (WAAM). Experiments were conducted for comparing the walls deposited in bidirectional and switchback strategies. The travel speed, inert gas flow rate, and number of deposited layers were kept constant for both the conditions. The grain growth behavior was identified from the bottom to top and welding direction. Finally, samples were extracted from the walls for mechanical property analysis and microstructural studies. Switchback mode produces ~ 70% γ′-phase whereas the bidirectional mode has ~ 77% γ′-phase in the matrix. Inconel 625 sample deposited using switchback technique revealed ~ 10-µm lesser primary dendritic spacing in the middle region and the standard deviation of overall structure is ~ 5 µm less compared with bidirectional deposition resulting in relatively higher average hardness. The switchback mode also results in ~ 2 µm lesser average secondary dendrite size among both the deposition strategies. The switchback deposition mode displayed a higher average yield strength (σy) (~ 440 MPa) than the bidirectional mode (~ 390 MPa) and approximately identical ultimate tensile strength (σu) with a 20-MPa variation. [ABSTRACT FROM AUTHOR]

Past few decades, light absorbing materials based on CuInGaSe2 and CdTe have been used for fabrication of thin film solar cells. But main issues arising from these absorbers are the limited availability and toxicity of some of their constituents, viz. In, Cd, and Te. At present, light absorbing materials based on Cu2ZnSnS4 (CZTS) is a best alternative to develop low cost and environmentally friendly component for next generation thin film solar cells. CZTS and their selenium alloy based devices showed the necessary potential for the development of thin film solar cells (TFSCs). There have been numerous attempts to synthesize TFSCs based on CZTS absorber. Various techniques available to deposit thin film absorber layer rely on vacuum and non-vacuum based methods. In this review, we focused on various deposition methods, their shortcomings and potential improvement for deposition of CZTS thin film. We have also addressed various parameters that affect CZTS thin film and its device performance including condition of annealing, variation of composition and doping of different elements. Finally, we have discussed the challenges and approaches for resolving the issue in the synthesis of CZTS based thin film solar cell. [ABSTRACT FROM AUTHOR]

BCN materials with varied structures are attracting attention for promising diverse applications. BCN materials are recognized for adaptable electrical properties, outstanding mechanical behavior, exceptional chemical inertness, and high thermal stability, which make them advantageous for corresponding applications in harsh environments. In this article, we thoroughly summarize BCN material theory, growth, properties, and applications. Properties of BCN thin films depend on the composition and growth technique, which facilitates in developing BCN films prevailing between insulating BN and semimetallic graphite. Regarding this, the effects of synthesis parameters on various BCN properties are examined. Dry and wet etching, which are imperative for device processing, are explored. Prompted by the success of graphene, graphene-analogous BCN nanomaterials are being researched intensively due to their unique chemical and physical properties. This article highlights BCN nanomaterials, their synthesis in different dimensions, and properties with prospective applications. We focus on their energy applications in supercapacitors, batteries, oxygen and hydrogen evolution reaction, water purification, and CO2 adsorption along with other biosensing applications. Performance of BCN nanomaterials is discussed and compared with the prevailing benchmark materials to present an evolutionary perspective of BCN nanomaterial progress. Finally, unresolved issues are highlighted, and future development opportunities are identified.

This paper reports the performance of dye-sensitized solar cell (DSSC) utilizing NiPd-rGO composite as counter electrode of the device. Various method of preparation of the counter electrode have been employed. It is found that the device utilizing the counter electrode prepared via liquid phase deposition technique (LPD) performs the highest power conversion efficiency that is 1.18 %. Next, the effect of the concentration of nickel chloride (NiCl2) on the performance of the device utilizing the composite prepared via LPD technique has been investigated. The device with the counter electrode prepared using of 50 mM NiCl2 demonstrates the highest efficiency of 1.07 %. [ABSTRACT FROM AUTHOR]

With the reduction of solid oxide fuel cells (SOFCs) operating temperature to the range of 600 °C–800 °C, metallic alloy with high oxidation resistance are used to replace traditional ceramic interconnects. Metallic interconnects is advantageous over ceramic interconnects; in terms of manufacturability, cost, mechanical strength, and electrical conductivity. To date, promising candidates for metallic interconnects are all Cr-containing alloys, which are susceptible to volatile Cr migration that causes cell degradation. As such, protective coatings have been developed to effectively inhibit Cr migration; as well as maintain excellent electrical conductivity and good oxidation resistance. This article reviews the progress and technical challenges in developing metallic interconnects; different types of protective coatings and deposition techniques for metallic interconnects for intermediate-temperature SOFC applications. [ABSTRACT FROM AUTHOR]

Three different deposition techniques were utilized to synthesize NiP-ZrO 2 nanocomposite coatings. The structural and mechanical merits for the as-prepared coatings were compared through XRD, XRF, SEM, AFM, microhardness, and nanoindentation analysis. The pulse-electrodeposition was the most suitable technique with a hardness value of 653HV 25. The erosion behavior for the different NiP-ZrO 2 coatings was investigated based on erosion duration, particles velocity, and impact angle. The results shows that the erosion rate decreases linearly with increasing angle of incidence and increases with increasing particle velocity. The erosion mechanism is mainly fracturing of splats and ploughing action at low particle velocity due to the ductility merits of the different coatings. In contrast, larger craters, radial cracks, and micro cuttings were observed at higher speeds. • NiP-ZrO 2 nanocomposite coatings were synthesized by three different deposition techniques pulse electrodeposition, electrodeposition, and electroless techniques. • Structural, morphological, mechanical, and erosion behavior of the different NiP-ZrO 2 coatings were studied thoroughly. • The mechanical performance of the different NiP-ZrO 2 coatings suggests pulse-electrodeposition be the most suitable technique for the fabrication of nanocomposite coating. • The erosion rate decreases linearly with increasing the angle of incidence; it increases with increasing particle velocity. The as-prepared electroless coatings show the highest erosion rate than electrodeposited and pulse electrodeposited coatings. • The deposition technique has a crucial effect on the coating morphology, mechanical properties, and erosion resistance as the pulse deposition method improves the NiP-ZrO 2 coating performance towards the erosion influences. [ABSTRACT FROM AUTHOR]

In this work we present a fully automated plasma-enhanced reactive thermal evaporation system (rf-PERTE) that can be used for the deposition of transparent metal oxide films without intentional heating of the substrate. The system and developed software enables the full control over critical deposition conditions such as mass flow of oxygen, process pressure, current flowing through crucible and rf-power. These parameters are automatically adjusted during the deposition thus keeping them in a narrow process window. This way, highly transparent and conductive coating can be deposited with a high degree of reproducibility of the optical and electrical characteristics. The resistivity of 9×10 -4 Ω-cm and the peak transmittance of 90% in the visible spectral range were achieved for indium oxide films deposited on glass substrates. This technique is also suitable for the deposition of transparent conducting coatings in a wide range of plastic materials for flexible solar cells. In particular, we have successfully deposited indium oxide on PEN (polyethylene naphthalate) sheets with electrical and optical properties approaching the ones for films on glass. [ABSTRACT FROM AUTHOR]

Stem-like nano-heterostructural MWCNTs/α-Fe 2 O 3 @TiO 2 (MCFT) composite, which is composed of TiO 2 coated α-Fe 2 O 3 nanoparticles firmly and uniformly anchored on multi-walled carbon nanotubes (MWCNTs), has been successfully fabricated via a facile layer-by-layer deposition technique and further investigated as the anode material for lithium-ion batteries (LIBs). It has been found that the as-obtained MCFT composite exhibits greatly improved electrochemical properties with satisfactory cyclability, admirable rate capability and favorable specific capacity for high-performance LIBs in comparison to MWCNTs/α-Fe 2 O 3 (MCF), originating from a synergistic effect of highly electric conductivity with good flexibility of MWCNTs, excellent structural stability of TiO 2 , and extraordinarily high theoretical capacity of α-Fe 2 O 3 . Specifically, it is capable of delivering a reversible capacity of as high as 770 mAh g −1 at 200 mA g −1 after 200 cycles and exhibiting a steady discharge capacity of 670 mAh g −1 even cycled at a large current density of 1000 mA g −1 . [ABSTRACT FROM AUTHOR]

This work describes progress towards achieving a flexible, high specific power and low‐cost photovoltaic (PV) for emerging large area space applications. The study reports the highest conversion efficiency of 15.3% AM1.5G for a CdTe device on ultra‐thin cerium‐doped cover glass, the standard protective material for extra‐terrestrial PVs. The deposition technique used for all of the semiconductor layers comprising the device structure was atmospheric pressure metal organic chemical vapour deposition. Improvements to the device structure over those previously reported led to a Voc of 788 mV and a relatively low series resistance of 3.3 Ω·cm2. These were largely achieved by the introduction of a post‐growth air anneal and a refinement of the front contact bus bars, respectively. The aluminium‐doped zinc oxide transparent conductive oxide, being the first layer applied to the cover glass, was subject to thermal shock cycling +80 to (−) 196°C to test the adhesion under the extreme conditions likely to be encountered for space application. Scotch Tape testing and sheet resistance measurements before and after the thermal shock testing demonstrated that the aluminium‐doped zinc oxide remained well adhered to the cover glass and its electrical performance unchanged. [ABSTRACT FROM AUTHOR]

The performance and hence pragmatic use of organic humidity sensors requires various factors to be addressed outside of progress in high-performance organic-based sensing materials. While important, evaluation of fabrication techniques also requires attention to optimise performance. Herein we report the effect of different application techniques on the humidity sensing performance of poly[ N -90-heptadecanyl-2,7-carbazole- alt -5,5-(40,70-di-2-thienyl-20,10,30-benzothiadiazole)] (PCDTBT) and [6,6]-phenyl-C 71 -butyric acid methyl ester (PC 71 BM) organic composites. Spin-coating, immersion and drop-casting techniques have been applied to prepare sensors. Field-emission scanning electronic microscopy (FESEM) analysis of the prepared films revealed different types of self-assembled nanorods and nanotubes to be formed. The morphological and self-assembled differences could be attributed to various crystallisation processes as a result of different deposition techniques. Capacitive responses of all three sensors have been studied as a function of relative humidity at room temperature. PCDTBT:PC 71 BM composites prepared through the immersion technique showed superior sensing performance including higher sensitivity (62.34 pF/ %RH) than sensors prepared through the spin coating (0.2 pF/ %RH) and drop-casting (7.5 pF/ %RH) techniques. The superior sensing performance of the sensor prepared through the immersion technique can be ascribed to both the nanotube and porous morphology exhibited. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: A method for the fixation of colloids by an ion-layer-gas-reaction-“ILGAR”-oxide layer is presented. The embedding of CdS nano-particles in an ILGAR-ZnO/Zn(OH)2-matrix is confirmed by transmission electron micrographs (TEM); the composition of the layer surface is analyzed by X-ray photoelectron microscopy (XPS). When these particles are fixed by an ILGAR-oxide layer on top of a solar cell the observed absorption and fluorescing properties of CdS nano-particles offer the possibility to reduce the absorption loss in the window layer. This is shown for a Cu(In,Ga)(S,Se)2-“CIGSSe”-based solar cell with an additional top CdSparticle/ILGAR-ZrO2-layer as a first example. The improvement of the device performance is proven by J(V)-characteristics and the external quantum efficiency. [Copyright &y& Elsevier]

The means of reducing nanoparticle contamination in the synthesis of carbon nanostructures in reactive Ar + H2 + CH4 plasmas are studied. It is shown that by combining the electrostatic filtering and thermophoretic manipulation of nanoparticles, one can significantly improve the quality of carbon nanopatterns. By increasing the substrate heating power, one can increase the size of deposited nanoparticles and eventually achieve nanoparticle-free nanoassemblies. This approach is generic and is applicable to other reactive plasma-aided nanofabrication processes. [ABSTRACT FROM AUTHOR]

The optical characteristics of one multimode fiber (MMF)-hollow core fiber (HCF)-structure when a nanofilm is deposited on it has been theoretically and experimentally studied. The electrostatic self-assembly method has been used as the deposition technique, and the polymers chosen are polydiallyldimethylammonium and Poly R-478. Two different types of HCF have been used for the fabrication of the devices: 10/150 and 50/150 μm inner and outer diameters, respectively. Depending on several design parameters, the transmitted optical-power characteristic of the device experiences important changes that could be interesting towards development of several practical optical devices. The length and thickness of the HCF segment, the refractive index of the material deposited, the angle of the light when it reach the HCF section, and the wavelength of the light source will be analyzed. [ABSTRACT FROM PUBLISHER]

Colloidally grown nanosized semiconductors yield extremely high-quality optoelectronic materials. Many examples have pointed to near perfect photoluminescence quantum yields, allowing for technology-leading materials such as high purity color centers in display technology. Furthermore, because of high chemical yield, and improved understanding of the surfaces, these materials, particularly colloidal quantum dots (QDs) can also be ideal candidates for other optoelectronic applications. Given the urgent necessity toward carbon neutrality, electricity from solar photovoltaics will play a large role in the power generation sector. QDs are developed and shown dramatic improvements over the past 15 years as photoactive materials in photovoltaics with various innovative deposition properties which can lead to exceptionally low-cost and high-performance devices. Once the key issues related to charge transport in optically thick arrays are addressed, QD-based photovoltaic technology can become a better candidate for practical application. In this article, the authors show how the possibilities of different deposition techniques can bring QD-based solar cells to the industrial level and discuss the challenges for perovskite QD solar cells in particular, to achieve large-area fabrication for further advancing technology to solve pivotal energy and environmental issues., (© 2022 Wiley-VCH GmbH.)

TiN, Cr–N, W, WC and WC/a-C: H coatings produced using Physical Vapour Deposition (PVD) method were investigated. TiN and Cr–N coatings were deposited using the cathodic arc evaporation (CAE-PVD) and reactive magnetron sputtering (RMS-PVD) techniques. W, WC and WC/a-C: H coatings were produced by the reactive magnetron sputtering (RMS-PVD) technique. Coatings were exposed to cavitation using a tunnel with a system of barricades. The influence of the deposition technique on the structure of the coating as well as on the degradation process has been discussed. It has been shown which degradation processes are independent of deposition techniques and which are dependent on them. The deposition technique had a higher impact on the droplet density (over 20-fold) than the deposited compound (nearly 2-fold). The highest density of droplets had TiN coatings deposited by the CAE-PVD technique, while the lowest had W-based coatings deposited by the RMS-PVD technique. The first symptoms of cavitation erosion of PVD coatings included the removal of some droplets from the coating surface and the coating undulation. The size of droplets did not affect their removal. Droplets can be divided into 1) droplets easy removable from the coating, 2) droplets requiring specific impact energy for their removal, and 3) droplets not removable from the coating, regardless of the degree of cavitation erosion development. Regardless of the deposition technique (CAE and RMS) and coating type (TiN or Cr–N), cavitation caused the phase transformation Fe-γ→Fe-α′ in the austenitic steel substrate. The intensity of this transformation depends on the deposition technique. High intensity of the phase transformation was obtained in the RMS coatings which are characterised by a low density of droplets. On the surface of the RMS coatings a larger size of puncture was formed than on the CAE coatings. It is shown that the droplets play an important role in the degradation as they are stress concentrators and also absorb some of the impact energy and affect the amount of energy used for fracture and transferred to the substrate. • The effect of the deposition technique of the PVD coatings on the degradation process caused by cavitation is studied. • The removal of droplets and coating undulation in the initial stage of erosion do not depend on the deposition technique. • The deposition technique affects the amount of impact energy transferred to the substrate. • The deposition technique affects the size of removed fragments of coatings. • The removal of droplets does not depend on their size. [ABSTRACT FROM AUTHOR]