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High light-harvesting efficiency and low interfacial charge transfer loss are essential for the fabrication of high-efficiency quantum dot-based solar cells (QDSCs). Increasing the thickness of mesoporous TiO2 films can improve the loading of pre-synthesized QDs on the film and enhance the absorbance of photoanode, but commonly accompanied by the increase in the unfavorable charge recombination due to prolonged electron transmission paths. Herein, we systematically studied the influence of the balance between QD loading and TiO2 film thickness on the performance of QDSCs. It is found that the relative thin photoanode prepared by the cationic surfactant-assisted multiple deposition procedure has achieved a high QD loading which is comparable to that of the thick photoanode commonly used. Under AM 1.5G illumination, Zn–Cu–In–Se and Zn–Cu–In–S based QDSCs with optimized 11.8 μm photoanodes show the PCE of 10.03% and 8.53%, respectively, which are comparable to the corresponding highest PCE of Zn–Cu–In–Se and Zn–Cu–In–S QDSCs (9.74% and 8.75%) with over 25.0 μm photoanodes. Similarly, an impressive PCE of 6.14% was obtained for the CdSe based QDSCs with a 4.1 μm photoanode, which is slightly lower than the best PCE (7.05%) of reference CdSe QDSCs with 18.1 μm photoanode.

we are studying the inhomogeneity of the thickness properties of the deposited ZnO:B film Based on glass substrates obtained by low pressure chemical viper deposition (LPCVD), which allow us to develop recommendations for optimizing the technological process for obtaining ZnO layers with characteristics that best meet the requirements for use in solar modules.The haze factor of the deposited ZnO film on a glass substrate with a size of 1300x1100 mm is 26.6% (average for glass) and 34% (maximum value), the average value of the value of the surface resistance is 17.6 O which is matching with a film thickness of 1657 nm, which leads to an improvement in the efficiency of the solar cell from (9.04%-10.1%).

Achieving high-quality perovskite films with uniform morphology and homogeneous crystallinity is challenging owing to the coffee ring effect (CRE) in the spray-coating technologies. In this study, an evaporation/spray-coating two-step deposition method is used to fabricate Cs0.19FA0.81PbI2.5Br0.5 light harvesters for perovskite solar cells (PSCs). Considering the solid-liquid reaction, we establish a reaction-dependent regulating strategy that inhibits CRE successfully and prepare a high-quality perovskite layer, wherein the solvent for the FAI/Br solution during the spraying process is changed from isopropanol to n-butyl alcohol (NBA). The retarded-drying-enhanced spreading of the NBA solution inhibits contact line pinning to suppress the capillary flows and increases the reaction between metal halides (CsI/PbI2) and organic salts (FAI/Br), which result in a reduction in the accumulation of solutes in the periphery effectively inhibiting CRE. Consequently, we obtain a high performance Cs0.19FA0.81PbI2.5Br0.5 PSC with a power conversion efficiency (PCE) of 19.17%. An enlarged perovskite film (10 × 10 cm2) containing 40 sub-cells is prepared. The average PCE of these devices is 18.33 ± 0.56%, proving the reliability of the “coffee ring” regulating strategy. This study provides an effective approach for CRE controlment in spraying technology to achieve high repeatability devices with good performance.

s Dendrite growth and by-products in aqueous Zn ion batteries have been impeded their rapid development as energy storage devices. Here we utilized a concentric-ring like additive, hexaoxacyclooctadecane (18-crown-6, 18C6), into typical ZnSO4 electrolytes to hook the Zn ion on surface by confinement effects during the electrochemical process. Combining experimental characterization and theoretical calculations, the dynamics were systematically investigated to offer a deceleration Zn deposition, in which a low charge transfer barrier and a high desolvation barrier were harvested simultaneously with 18C6. It regulated the solventized structure of Zn ions and held the steady hydrophobic interface during the electrochemistry process. The by-products yield was extremely low. Zn symmetric cells be cycled over 2400 h at 1 mA cm−2 and 1 mAh cm−2. These studies provided an effective strategy to reach the dendrite-free and high-density Zn energy storage devices.

In history, semiconductor-metal-semiconductor transistor (SMST) was proposed for frequency improvement. However, a general fabrication method is still missing due to the unsolved technological problem of deposition of a general crystalline semiconductor on metal, and a thinner metal base is also difficult to be fabricated with high quality. Recently, due to the atomic thickness of graphene, the concept of semiconductor-graphene-semiconductor transistor (SGST) has emerged which leads to the renaissance of SMST, however the experimental study is in its infancy. In this letter, SMST and SGST are fabricated using Si membrane transfer. It is found the common base current gain can be improved from about 0.5% in a Si-Au-Si transistor to about 1% in a Si-Gr-Ge one, and to above 10% in a Si-Gr-Si one, which is attributed to both the ultra-thin thickness and the quantum capacitance effect of graphene.

In this paper, 50 vol% TiCp/Ti6Al4V composites without pores, cracks or poor fusion were fabricated by laser melting deposition (LMD) technology using 500 W laser power (lower power, LP) and 1000 W laser power (higher power, HP). The microstructure of different deposited layers was analyzed and the corresponding microhardness was measured. The results show that the composites are composed of undissolved TiC, in-situ TiC (eutectic TiC and primary TiC), α Ti and β Ti. It is interesting that the microstructure from the bottom layer to the top layer presents a graded distribution when all layers have the same composition. The eutectic TiC is mainly formed in lower layers while the primary TiC is mainly in upper layers. With increasing layer number, the size and number of the primary TiC grains increase and the primary TiC grows gradually from granules into dendrites, however, the number of the undissolved TiC particles decreases along the depositing direction. The simulation results show that the peak temperature of deposited layer increases while the cooling rate decreases with increasing layer number. Different thermal history affects the diffusion of carbon and the evolution of TiC, and then affects the microstructure distribution of the composites. This graded microstructure leads to the graded distribution of microhardness. The microhardness of the LP composite rises from 432.5 HV to 488.1 HV, while the HP composite rises from 435.5 HV to 604.3 HV from the bottom layer to the top layer, respectively.

The synergistic effect of Mo and Zr additions on microstructure evolution, room-temperature fracture toughness and microhardness of Nb-22Ti-15Si-xMo-yZr (x = 4,8, y = 3,6) alloys manufactured by laser directed energy deposited (L-DED) have been investigated. The major phases in as-deposited 4Mo-3Zr alloy are Nb solid solution (Nbss), Nb3Si and γ-Nb5Si3. The Nb3Si phases disappear with increasing Mo content to 8 at.% or increasing Zr content to 6%. γ-Nb5Si3 precipitates formed in the Nbss of as-deposited xMo-yZr alloys due to the cyclic re-heating, and the γ-Nb5Si3 precipitates and Nbss matrix exhibits orientation relationship (OR) of [001]Nbss//[ 1 ¯ 112]γ and (110)Nbss//(01 1 ¯ 0)γ in as-deposited 4Mo-6Zr alloy. The microstructure of xMo-yZr alloys became relative homogeneity and the Nbss matrix showed the better continuity after the heat treatment (1400 °C/30 h). The Nb3Si phase has transformed into Nbss and α-Nb5Si3 with the OR have been determined as {100}Nbss//{100}α and{111}Nbss//{111}α in the heat-treated 4Mo-3Zr alloy. When Mo content increase to 8at.%, a part of γ-Nb5Si3 phase also transformed into the α-Nb5Si3 phase with the OR have been determined as {11 2 ¯ 0}γ//{110}α and {10 1 ¯ 0}γ//{111}α after heat treatment. Among the as-deposited alloys, the 4Mo-6Zr alloy has the highest fracture toughness KQ with the lowest hardness. The average KQ of 4Mo-6Zr and 8Mo-6Zr alloys increased by 28% and 30% after the heat treatment, and reached 13.61 and 11.43 MPa•m1/2, respectively. The hardness of Nb-22Ti-15Si-xMo-yZr alloys is significantly decreased after the heat treatment.

The metal oxides-based chemiresitive gas sensors have attracted enormous interest because of their exellent sensing perforamcnes, which have emerged as very promising candidates for gas monitoring. However, from the view of organophosphorus compounds detection, a unique combination of low detection limit and fast respons/recovery rate remains challenging. Herein, the synersgitic effects of oxygen vacancy engineering and surface gold decoration enabling excellent sensing performances for detection of dimethyl methyl phosphonate (DMMP, a typical organophosphorus) is reported. To demonstrate the proof of concept, Au nanoparticles (NPs) decorated oxygen vacancy-enriched SnO2 hybrids (designated as Au-O-SnO2) were designed as sensing materials, where the O-SnO2 samples were fabricated by introduction of oxygen vacancies onto commercial SnO2 through organometallic chemistry-assisted approach using (CH3)2SnCl2 as precursor, followed by deposition of Au NPs by an in-situ reduction routine. After optimizing Au NPs content in hybrids (1 wt%, 3 wt%, 5 wt% and 7 wt%), O-SnO2 decorated with 5 wt% Au NPs (designated as Au-O-SnO2-5) exhibits excellent DMMP sensing performances, such as, an enhanced recoverable response of 1.67 to 680 ppb DMMP, low detection limit of 4.8 ppb, short response time of 26 s and recovery time of 32 s, as well as good selectivity, which are much better than that of commercial SnO2 (C-SnO2) and O-SnO2, and Au NPs decorated C-SnO2. Based on the detailed investigation, the enhanced DMMP sensing performances of Au-O-SnO2 hybrids can be mainly ascribed to the synergistic effect of increasing surface active sites induced by oxygen vacancies, the chemical and electronic sensitization of Au NPs. As a result, Au-O-SnO2-5 hybrids display relatively low activation energy of 24.11 kJ/mol for DMMP oxidization, which is lower than that of O-SnO2 (35.54 kJ/mol). Our results provide a feasible method for boosting sensing performances for DMMP detection, paving new way for fabrication of metal oxides-based gas sensors for rapid detection of trace organic compounds with complexed structures.

In the present work, nanostructured hydroxyapatite (HA)-containing coating was prepared on a Ti surface by ultrasonic mechanical coating and armoring (UMCA). A Ti plate was pre-coated with HA slurry, followed by UMCA, which was achieved by high-frequency ZrO2 ball bombardment. The UMCA process comprised several cycles of pre-coating and ball bombardment, providing high amounts of HA and good coating adhesion. The coating mainly consisted of nano-HA particles (less than 10 nm) and a small amount of Ti. Furthermore, the deformation structures of the Ti surface region were characterized in a nanocrystalline layer with a grain size of 50–200 nm. Additionally, the coating exhibited improved bioactivity and corrosion resistance in Hanks’ balanced salt solution than the Ti surface. Furthermore, the in vitro cytotoxicity test assessed that the HA-containing coating was non-cytotoxic.

Ring-like residual deposits are often observed after drying suspension droplets on surfaces. That introduces a crucial defect in practical applications, such as ink-jet printing that requires a uniform deposit. In this study, depositions after drying sessile/pendant droplets with silica/polystyrene particles were examined to identify the effect of gravitational sedimentation of particles on self-pinning and deposition pattern. The suspension droplet with larger polystyrene (or silica) particles would trigger the self-pinning at larger (or smaller) particle concentrations. The deposition pattern of pendant drops with silica particles is hill-like. This is due to the large density difference between silica and water to induce high sedimentation velocity, and the particles would precipitate and aggregate along the air–liquid interface to form a hollow shell deposit. The depositions for suspensions with bi-dispersed particles, the larger silica particles would accumulate at the bottom of the deposit due to the higher sedimentation velocity, in contrast to the well-mixed in the deposits for bi-dispersed polystyrene particles. The sedimentation and capillary flow velocities were calculated and discussed. These new findings reveal that the particle density (gravity effect) can be used to adjust the sedimentation velocity to control the deposition morphology and particle size distribution even to suppress the coffee-ring effect.

A simplified computational scheme for “deposition” of a metallic (Pd) monolayer on semi-ionic supports is considered. An arbitrary selection of the initial position of the deposited layer relative to the surface of the support cannot provide the best solution for an optimal atom–atom binding. The energy and/or geometry changes were checked relative to a slide of the mono- and bilayers in parallel to the support layer and re-optimization. Two types of possible consequences are shown at the slide length of 1–3 A for γ-Al2O3(110), monoclinic ZrO2(001) (or m-ZrO2), and rutile TiO2(001) (or TiO2 below). First consequence option: either the Pd monolayer completely collapses after the shift/optimization, or it yields a new geometry (at γ-Al2O3(110) and m-ZrO2) at different steps. Second consequence option: the shift leads to a loss of the Pd stabilization while the ordered monolayer's geometry is retained (at TiO2 and m-ZrO2). The extent of such destabilization varies depending on the strength of the interaction with the support. It is thus recommended to verify Pd stabilization energy by sliding/optimizing the monolayer along one or two monolayer directions in order to avoid its energy underestimation. The activity of such monolayers for modelling catalysis is demonstrated using H2O dissociation in the Pd monolayer/rutile system.

Nano-layers are very important in optics applications such as reflectance devices, anti-reflection coating, and solar cell applications according to thickness. The nano-layers (one-layer (25 nm), one-layer (40 nm), two-layers (65 nm), and three-layers (90 nm)) of Cu2O were fabricated by thermal evaporation, with the rate of deposition was 0.2 nm/sec. Morphological properties were examined through Atomic Force Microscope (AFM). The AFM results refer to very smooth prepared films; the roughness average was about 0.275–0.615 nm and the root mean square was about 0.378–0.765 nm. The absorbance spectra in the range of 200–1100 nm were documented using a UV–Visible spectrophotometer. If the number of layers (thickness) increased, the absorbance increased while the transmittance decreased. The energy gap reduced as the thickness of the material increased.

In this letter, a threshold switching (TS) selector with Ag doping-based nano-polycrystalline ZnO switching layer (SL) having (002) preferred orientation has been manifested, without incorporating an active Ag metal layer, using a facile co-sputtering deposition technique. The TS selectors with extremely controlled doping of ~0.14 at. % Ag concentration showed remarkable electroforming (EF)-free selection behavior such as gigantic selectivity (~1011), extreme-low off-current (~10 fA), high on-current density (~1.6 MA/cm2), ultra-steep switching slope (~0.8 mV/decade), satisfactory endurance (>106), fast switch-on speed (~38 ns) and relaxation speed (~64 ns), and high device yield (~90%). Furthermore, selector devices showed reproducible selection behavior with stable threshold voltage (Vth) having merely 8% variances.

Developing photocatalyst with effective charge separation and fast surface reaction kinetics is crucial to high-efficiency photocatalytic H2 evolution. Herein we spatially separate the reductive and oxidative reaction sites of ZnIn2S4 nanosheet and accelerate the hole transfer process by simply depositing cobalt phosphate (CoHxPOy, noted as Co-Pi), a non-precious co-catalyst, on its basal plane. Theoretical calculations combined with comprehensive characterizations reveal that Zn vacancies induced deep local energy levels serve as hole trap states to pin the photogenerated holes on (0 0 1) surface of ZnIn2S4. Upon Co-Pi deposition, Co atoms preferentially bond with S atoms nearby the Zn vacancies of ZnIn2S4. Taking advantage of the formation of Co-S bonds, Co-Pi acts as a hole receptor to extract the trapped holes effectively. As the photocatalytic activity of ZnIn2S4 is caused by active S atoms on its edge side, deposition of Co-Pi on planar side of nanosheets helps electron-hole migration to different facets. As a result of inert facet activation and spatial carrier separation, Co-Pi/ZnIn2S4 exhibits a superior photocatalytic H2 evolution rate of 10.19 mmol g-1h−1 under visible light, which is superior to most of reported ZnIn2S4-based photocatalysts. This work will provide novel insights into the activation of inert basal planes of two-dimensional photocatalysts.

In the present study, CuFeO vertical nanocolumnar structured arrays are deposited on fluorine-doped tin oxide substrates by reactive ballistic deposition technique in an oxygen atmosphere by fixing the deposition angle at 85°. Scanning electron microscopy images shows the presence of arrays of individual columns. The photocurrent density of the CuFeO2 annealed at 650 oC for 2 h in argon is determined to be -0.22 mA cm-2 at 0.4 V versus RHE in 1 M NaOH under AM 1.5 G illumination, while the same annealed in air exhibits a photocurrent density value of 0.12 mA cm-2 at 1.23 V versus RHE. Here, the film annealed in an argon atmosphere at 650 °C exhibits a p-type characteristic with cathodic photocurrent, while the same annealed in air depicts an n-type characteristic with anodic photocurrent. The p-type character was induced by the Cu vacancies and the shift in the conductivity from n-type to p-type is induced by phase transition formation of delafossite CuFeO2 from copper modfied FeO. The generation of photocurrent density from p-CuFeO2 is expected to be from the presence of Cu2+/Cu+ redox couple which is evidenced by X-ray photoelectron spectroscopy.

The selective hydrogenation of C C to C=C bonds is an important step, yet remains to be a great challenge in chemical industry. In this study, we have revealed the influence of Pd deposition pH value on the catalytic performance of Pd-CuO/SiO2 catalyst for the semi-hydrogenation of 2-methyl-3-butyn-2-ol (MBY). Trace amount of Pd (about 500 ppm) was loaded via deposition-reduction method on CuO/SiO2 support by using H2PdCl4 solution as precursor and NaBH4 as reductant, respectively. The pH value at which Pd was deposited was adjusted to about 5 and 7 by adding NaOH solution. The obtained catalysts were characterized by several techniques including XRD, TEM, H2-TPR, etc. In the case of pH value of 5, the CuO was partially dissolved during the deposition and then co-reduced with Pd2+ by NaBH4, forming PdCu alloy structure in sub-nanometer. In contrast, no PdCu alloy structure was observed when pH value was 7. The kinetics of MBY semi-hydrogenation over both catalysts were compared. The former PdCu alloy catalyst showed very high selectivity towards the semi-hydrogenation of MBY due to its low activity in hydrogenation of C=C bond in 2-methyl-3-buten-2-ol (MBE). The results herein demonstrated that the pH value where Pd was deposited played a crucial role in determining the catalytic performance of PdCu catalyst.

Ta3N5 has suitable band positions for visible light photocatalytic hydrogen production from water splitting. However, fast self-recombination of electrons and holes is a drawback for its low efficiency. A Ta3N5/WO3 Z-scheme was therefore considered to solve this problem. Furthermore, a nanohoneycomb (nHC) structure was designed and fabricated based on solution-based nanosphere lithography to offer higher surface area for reaction. The cell size of the nHC was controlled by using 400-, 200-, and 100-nm polystyrene nanospheres as the mask. Under visible light irradiation, the hydrogen generation rates of Ta3N5@WO3 film and Ta3N5@100-nm WO3 nHC were measured to be 4.6 and 8.1 μmol/g·h, respectively, whereas that of pure Ta3N5 nHC was negligible. With deposition of Pt cocatalyst, the hydrogen generation rates for Ta3N5@WO3 film and Ta3N5@100-nm WO3 nHC were further raised to 9.9 and 16.6 μmol/g·h, confirming the effectiveness of the structure design.

Aqueous Zn-ion batteries (AZIBs) are promising candidates for large-scale energy storage owing to their intrinsic safety and low cost. However, the formation of Zn dendrite caused by uneven deposition on Zn anode severely impedes the lifespan of AZIBs. Herein, we propose a green and low-cost additive, nettle extract (NE), to guide the uniform Zn deposition via in-situ engineered zincophilic sites. We show by both experiments and theoretical calculations that the zincophilic molecules contained in NE can adsorb on Zn anode surface to offer more effective sites for Zn nucleation, thus effectively suppressing the dendrite growth. Significantly, the Zn||Zn symmetric cell with NE can stably cycle over 2200 h at 5 mA cm−2 with 5 mAh cm−2 capacity. A Zn||polyaniline/carbon felt full cell also gains 84.9% capacity retention after 1500 cycles. Our strategy of engineering zincophilic sites on Zn anode via plant extracts additives ushers in new possibilities to develop dendrite-free Zn anode.

SiC nanowires reinforced C/(PyC-SiC)n multilayered matrix composites (SM-CS for short) were prepared by combined with sol-gel and chemical vapor infiltration (CVI) method. Firstly, (PyC-SiOC)n multilayered structure was formed by cycles of impregnation and deposition. Then SiOC was transformed into SiC by heat-treatment, and (PyC-SiC)n multilayered structure would be obtained. At the same time, the PyC layer which was designed as the outmost layer could decrease gas supersaturation to form in-situ tubular SiC nanowires on the surface of multilayered structure. The results of three-point bending test showed that the maximum force of SM-CS composites was increased by the number of cycles of the preparation process, which were up to enhanced by 74.38% compared with C/C composite materials. The fracture surface showed that the improvement was due to the multiscale reinforcing system of (PyC-SiC)n multilayered structure and SiC nanowires. Multilayered structure can protect carbon fibers and release stress concentration by induction of cracks. And the mechanical interlocking effect of SiC nanowires could reinforce bonding force of the remaining matrix.

To improve the hydrothermal durability of Cu-SSZ-13 selective catalytic reduction (SCR) catalyst, a thin Al2O3 modification layer was coated on the external surface of Cu-SSZ-13 by a chemical liquid deposition (CLD) method. The high-temperature SCR activity of the Al-modified Cu-SSZ-13 can be maintained upon 750-800 °C hydrothermal aging, and over-oxidation of NH3 is largely inhibited. Based on H2-TPR and EPR results, it is revealed that CuAl2O4-like species forms upon Al modification and converts further to CuAlO2-like species during aging. The high affinity of Al-containing species (i.e., Al2O3 and CuAl2O4-like species) with Cu(OH)2 is suggested by DFT calculations, indicating that Cu(OH)2 detached from ion-exchange sites are captured by Al to form CuAlO2-like species instead of CuO-like species. The passivation of aggregated Cu species by coated Al leads to somewhat weakened low-temperature SCR activity, but successfully preserves the high-temperature SCR performance upon aging, which can be applied to high-temperature SCR scenarios.

Understanding the growth mechanism of TiO2 nanorods (TNRs) is critical for producing high-performance materials with morphology and structure control. TNRs on FTO glass were prepared by hydrothermal method in acidic solution. The structural and morphological characteristics of thin films were investigated for different temperatures and reaction times. By the hydrolysis and protonation, monomers Ti(OH)n(OH2)6-n](4-n)+ can be formed at ambient conditions. TNRs were formed through the bonding between these monomers by olation and oxolation reactions during hydrothermal process. During the hydrothermal growth of TNRs on FTO glass, precursors of TNRs and nanoflowers were observed in the reactive solution and on top of TNR thin films. The preferential deposition of precursors and TiO2 nanostructures on top of primary TNRs from solution resulted in significant changes in their morphology, structure, and growth orientation. A new possible growth mechanism of TNRs is proposed based on these experimental observations. Our preliminary results show positive signs to apply the prepared TNRs as electron transfer layer of perovskite solar cells (PSCs). This study will become the basis for our further researches to apply the prepared TNR thin films with the most suitable structural and morphological properties to high-performance PSCs as well as other photovoltaic devices.

Hybrid nanocomposites (NCs) of Mn3O4 nanorods and 2D materials (MoS2 or graphene) nanosheets are successfully deposited on nickel foam porous substrate at room temperature using a one-step kinetic spray process in low-vacuum conditions. Mn3O4-based NCs are utilized for the electrocatalytic detection of H2O2 in 0.1 M NaOH. The synergy improvement between the Mn3O4 nanorods and either MoS2 or graphene nanosheets improved the non-enzymatic detection of H2O2. All modified electrodes exhibit a wide linear detection range from 0.2 to 1 mM. The working electrodes with Mn3O4 nanorods reveal high sensitivity of 2320 μA mM−1 cm−2 toward H2O2 reduction. The hybridization between Mn3O4 nanorods and either MoS2 or graphene enhances the electrocatalytic reduction sensitivity to 3220 or 5400 μA mM−1 cm−2, respectively. Furthermore, the modified electrodes with the Mn3O4-2D material hybrid NCs exhibited high electrocatalytic reduction selectivity for H2O2 in 0.1 M NaOH compared with other interfering species.

Mixed phase materials in the quasi binary diopside (CaMgSi2O6) – molybdite (MoO3) system were synthesized by a precipitation method. Materials were fabricated with diopside to molybdite ratios of 1:0, 10:1, 5:1, 2:1 and 1:1. XRD, SEM and EDS results show that alongside the initial diopside phase, phases such as calcium molybdate CaMoO4, rod-like enstatite MgSiO3 and cristobalite SiO2 formed as the molybdite content increased, and diopside was entirely absent at the highest molybdite content. At lower Mo content, mixed phase materials showed higher hardness and slower biodegradation in SBF relative to pristine diopside, while maintaining reasonable hydroxyapatite (HAp) formation capability. In contrast, materials with higher molybdite content exhibited lower hardness and bioactivity. The variation in the mechanical and bioactive performance could be attributed to the presence of bulk CaMoO4, acting as a reinforcement, and rod-like MgSiO3 with a highly porous and fragile structure. The trend of hardness is not consistent to the proportion of the component phases could be attributed to morphologies, interfaces, and densities of the samples. Both of secondary phases had poorer HAp deposition compared to pure diopside, indicating the MoO3 addition lowered mixed phase CaMgSi2O6 – MoO3 bioceramics’ ability to form Hap. The results suggest that moderate addition of molybdite to diopside would be an effective pathway towards crystalline bioceramics with enhanced performance.

Plasma electrolytic oxidation (PEO) has attracted significant attention as a promising eco-friendly technology for the deposition of ceramic-like oxide coatings with superior wear- and corrosion resistance as well as biomedical, catalytic, magnetic, dielectric and optical properties. However, the industrial implementation of PEO has been hindered by a poor understanding of the mechanisms underlying plasma-assisted electrochemical coating formation. This study compares the characteristics of PEO processes on different valve metals in a dilute aqueous solution of NaOH and Na2SiO3 under pulsed unipolar and bipolar polarisation conditions. The focus is given to the influence of the nature of the valve metal on the transition to the soft sparking regime characterised by reduced energy consumption whilst yielding sintered coating materials enriched with crystalline phases. In-situ dynamic voltammetry analysis was employed to study the effects of the net current ratio and local negative charge injection using diagnostic pulses embedded in the polarisation signal. It has been demonstrated that soft sparking is a characteristic feature of valve metals such as Mg, Al, Zr and Ta that form insulating surface oxides with negligible electronic conductivity, whereas Ti and Nb form semiconducting oxides, which do not exhibit a characteristic voltage drop, although some features of spark softening were detected. This generalisation paves a way for implementation of a model known as ‘digital twin’ to the rational design of the PEO processes for deposition of the functional ceramics.

In this paper, C and Ti were used as the deposition atoms in the molecular dynamics model. The effects of Ti doping percentages (2, 8, 14, and 20 atom %) on the structure and internal stress of a-C films were investigated. The results showed that with the increase in the Ti percentage, the density of the intrinsic zone is gradually increased, while the growth rate is slowly decreased. The internal stress is gradually changed from compressive stress to tensile stress. Among them, when the Ti percentage is 14 atom %, the internal stress is closer to 0. The C percentage with sp3 hybridization is decreased, while those with sp2 and sp hybridizations are increased. The positions of the first and second peaks in the RDF were shifted to the left. Moreover, the distribution of bond lengths and bond angles in the intrinsic zone tend to change from diamond to graphite, which proves that Ti doping leads to the graphitization of a-C films. In addition, Ti doping affects the internal stress of a-C films by changing the C percentage with sp3 hybridization in them.

3D porous iron (Fe) scaffolds with interconnected open pores are promising candidates for bone repair. However, the bare 3D porous Fe scaffolds lack of antibacterial activity and the ability for cell adhesion. Herein, atomic layer deposition technique was used to deposit nanometer-thick zinc oxide (ZnO) layer onto the skeleton of 3D porous Fe scaffolds with interconnected open pores. The effect of ZnO thin film on the in vitro degradation behavior, antibacterial activity and cytocompatibility of 3D porous Fe scaffolds was systematically evaluated. The results showed that a dense ZnO thin film with a thickness of 76 nm was uniformly deposited on the skeleton of the porous Fe scaffolds. The thickness of ZnO thin film could be easily controlled by the deposition cycles. The deposited ZnO thin film significantly reduced the degradation rate of porous Fe scaffolds and the fabricated ZnO coated porous Fe scaffolds demonstrated strong antibacterial ability against both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus, while did not significantly affect cytocompatibility and could also promote cell adhesion.

Wire arc additive manufacturing (WAAM) is advantageous for fabricating large-scale metallic components; however, a high geometric accuracy as that of other AM techniques cannot be achieved because of the deposition process with a large layer. This study focuses on the WAAM process based on gas metal arc welding (GMAW). To clarify the influence of shielding gas used to protect a molten metal during fabrication on the geometric accuracy of the built part obtained via the GMAW-based WAAM process, the influence of the metal transfer behavior on the geometry and surface roughness of the fabricated structures was investigated via visualization using a high-speed camera when single and multilayer depositions were performed under different heat inputs and gases. It is known that Ar gas is not suitable for welding steel because it cannot provide the desired arc stability and weld bead characteristics. The results reveal that the arc is stable in the multilayer deposition of the WAAM process, and the short-circuit of the metal transfer at the heat input of 1.17 kJ/cm enables smoothing of the fabricated surface with large irregularities. Better arc stability under Ar gas is achieved when the oxygen content of the fabricated surface is 22 wt%. Furthermore, the short-circuit between the metal droplet and the fabricated surface, where the molten pool is insufficiently formed, resulted in a hump formation. The results indicate that proper use of Ar gas can improve the surface quality when depositing on rough surfaces.

Cylindrical permalloy nanowire arrays are prepared by employing anodic aluminum oxide (AAO) template-assisted electrochemical deposition method. To prepare high-quality permalloy nanowire, the effects of different deposition parameters (pulse current density, concentration and pH value of the electrolyte, and deposition temperature) on the chemical composition, uniformity, and magnetic properties of the nanowires are systematically investigated. A high-quality permalloy nanowire with good magnetic properties of $${M}_{\text{S}}\approx 5.7\times {10}^{5}\, \mathrm{A}/\mathrm{m}$$ and $$\alpha \approx 0.04$$ has been successfully prepared by optimizing the preparation scheme, which can provide technical support for mass production of cylindrical permalloy nanowire for spintronic devices.

A comparison of hexagonal boron nitride (hBN) layers grown by chemical vapor deposition on C-plane (0001) versus A-plane (1120) sapphire (α-Al2O3) substrate is reported. The high deposition temperature (>1200 °C) and hydrogen ambient used for hBN deposition on sapphire substantially alters the C-plane sapphire surface chemistry and leaves the top layer(s) oxygen deficient. The resulting surface morphology due to H2 etching of C-plane sapphire is inhomogeneous with increased surface roughness which causes non-uniform residual stress in the deposited hBN film. In contrast to C-plane, the A-plane of sapphire does not alter substantially under a similar high temperature H2 environment, thus providing a more stable alternative substrate for high quality hBN growth. The E2g Raman mode full width at half-maximum (FWHM) for hBN deposited on C-plane sapphire is 24.5 ± 2.1 cm-1 while for hBN on A-plane sapphire is 24.5 ± 0.7 cm-1. The lesser FWHM standard deviation on A-plane sapphire indicates uniform stress distribution across the film due to reduced undulations on the surface. The photoluminescence spectra of the hBN films at 300 and 3 K, obtained on C-plane and A-plane sapphire exhibit similar characteristics with peaks at 4.1 and 5.3 eV reported to be signature peaks associated with defects for hBN films deposited under lower V/III ratios. The dielectric breakdown field of hBN deposited on A-plane sapphire was measured to be 5 MV cm-1, agreeing well with reports on mechanically exfoliated hBN flakes. Thus, under the typical growth conditions required for high crystalline quality hBN growth, A-plane sapphire provides a more chemically stable substrate.

We investigate different postseparation process routes for silicon heterojunction (SHJ) half solar cells, separated by thermal laser separation. SHJ half cells with and without aluminum oxide (Al 2 O 3 ) deposition as edge passivation layer undergo different annealing processes, including i) a hotplate; ii) an inline oven; and iii) an ultrafast light soaking process. SHJ half cells with an initial efficiency of 21.7% reach 21.9% after Al 2 O 3 deposition and inline oven annealing (pseudo fill factor, pFF , increase of 0.3% abs and series resistance R S decrease by −0.05 Ocm 2 ). The light soaking process is known to lead to improved surface passivation and carrier transport for SHJ cells. For light soaking processed SHJ half cells, an 21.9% efficiency is obtained ( R S reduction by −0.13 Ocm 2 and open-circuit voltage V OC increase by +2 mV compared to the initial half cell). By combining Al 2 O 3 deposition and subsequent light soaking, SHJ half cells reach 22.1% efficiency, resulting from the combined benefits for pFF , R S , and V OC of the two processes. No additional thermal annealing of the Al 2 O 3 layer is necessary, proving that the light soaking process is sufficient to activate the Al 2 O 3 passivation. This allows for a two-step postseparation process sequence, resulting in SHJ half cells featuring similar efficiencies to light soaking processed full cells. SHJ half cells, integrated into one-cell modules after Al 2 O 3 deposition and light soaking, show an efficiency advantage of +0.3% abs in comparison to modules with untreated half cells. Thus, we demonstrate the possibility of compensating separation losses for SHJ half cells and the transferability of the improvements to module level.

The amplitudes of the first Shapiro steps for an external signal with frequencies of 72 and 265 GHz are measured as function of the temperature from 20 to 80 K for a 6 μm Josephson grain boundary junction fabricated by YBaCuO film deposition on an yttria-stabilized zirconia bicrystal substrate. Non-monotonic dependences of step heights for different external signal frequencies were found in the limit of a weak driving signal, with the maxima occurring at different points as function of the temperature. The step heights are in agreement with the calculations based on the resistively–capacitively shunted junction model and Bessel theory. The emergence of the receiving optima is explained by the mutual influence of the varying critical current and the characteristic frequency.

Copper metallization of PEEK were performed by high-pressure cold spraying (HPCS) to obtain a high deposition efficiency (DE). Cu/PEEK interface and Cu/Cu interface produced under the same HPCS deposition conditions were compared in terms of feature and bonding strength. The DE of the Cu/Cu combination is 73% whereas the Cu/PEEK case gives a DE of 79%. These DE values are comparable whereas the bonding strengths are very different. The Cu/Cu interface reached values of 30−50 MPa while the Cu/PEEK interface was less resistant (0.2−10 MPa). SEM observations of the fracture surfaces exhibit the differences between these two combinations. The particles were less deformed and showed apparent decohesion for the Cu/PEEK case. In addition, craters due to particles decohesion and rebound were observed whereas the Cu/Cu case showed more particle flattening. The Cu/PEEK debonding was characterized by an adhesive failure. The copper powders that penetrated the PEEK substrate came out leaving craters. In addition, the weakly bonded Cu/Cu particles within the Cu/PEEK interface were conducive to a rupture. These features explain the low bonding strength of the Cu/PEEK interface. In case of Cu/Cu combination, the interface breaks by cohesive failure and the fracture surface evidenced flattened particles within the deposit. The greater adhesion strength of the Cu/Cu interface is then due to a more plastic deformation produced during the inter-collision of Cu powders during the HPCS deposition.

With nearly 100% yields for mobile charge carriers in organic solar cells (OSCs), the relatively large photovoltage loss (ΔVoc) is a critical barrier limiting the power conversion efficiency of OSCs. Herein, we aim to improve the open-circuit voltage (Voc) in OSCs with non-fullerene acceptors via sequential film deposition (SD). We show that ΔVoc in planar heterojunction (PHJ) devices prepared by the SD method can be appreciably mitigated, leading increases in Voc to 80 mV with regard to the Voc of bulk heterojunction devices. In PHJ OSCs, the energy level of intermolecular charge-transfer states is found to increase with a decrease in the level of aggregation in the solid state. These properties explain the enhanced electroluminescent quantum efficiency and resultant suppression of the voltage losses induced by nonradiative charge recombination and interfacial charge transfer. This work provides a promising strategy for tackling the heavily discussed photovoltage loss in OSCs.

Zn anodes have gained intensive attention for their environmental-friendliness and high volumetric capacity but are limited by their severe dendrite formation. Understanding the initial nucleation behavior is critical for manipulating the uniform deposition of Zn. Herein, the allometric growth and dissolution of Zn in the initial nucleation and early stages are visualized with in situ atomic force microscopy in aqueous ZnCl2 electrolytes. Zn nuclei grow via a horizontal radial direction and dissolve reversibly in a top-down process. The critical nucleation radius and density are dependent on the electrolyte concentration of ZnCl2, namely, the initial nucleus size is proportional to the ratio of surface free energy between deposited Zn and the electrolyte and overpotentials for Zn electrodeposition, and the density is inversely proportional to the cube of this ratio. This investigation provides guidelines for regulating uniform metal electrodeposition and yields benefits for the development of anode-free batteries.

Dentin bonding based on a wet-bonding technique is the fundamental technique used daily in clinics for tooth-restoration fixation and clinical treatment of tooth-related diseases. Limited bonding durability led by insufficient adhesive infiltration in the demineralized dentin (DD) matrix is the biggest concern in contemporary adhesive dentistry. This study proposes that the highly hydrated noncollagenous protein (NCP)-formed interfacial microenvironment of the DD matrix is the root cause of this problem. Meanwhile, the endogenous phosphate groups of the NCPs are used as pseudonuclei to rapidly induce the formation of amorphous CaF2 nanoparticles in situ in the interfacial microenvironment. The DD matrix is thus reconstructed into a novel porous structure. It markedly facilitates the infiltration of dentin adhesives in the DD matrix and also endows the DD matrix with anticollapsing capability when water evaporates. Whether using a wet-bonding or air-drying mode, the bonding effectiveness is greatly promoted, with the 12 month bonding strength being about twice that of the corresponding control groups. This suggests that the nanoreinforced DD matrix eliminates the dependence of bonding effectiveness on the moisture status of the DD surface controlled only by experiences of dentists. Consequently, this bonding strategy not only greatly improves bonding durability but also overcomes the technical sensitivity of bonding operations of the total-etched bonding pattern. This exhibits the potential to promote dentin bonding and is of great significance to dentistry.

The effect of the substrate temperature during the deposition of a ZnO:Al (AZO) window layer on the performance of Cu(In, Ga)Se2 (CIGS) solar cells was studied. Although the structural, electrical and optical properties of separate AZO films are enhanced with higher substrate temperature, the overall performance of final CIGS solar cells is deteriorated. At higher substrate temperature, the diffusion of Cd, Zn and Al into the CIGS absorber layer was observed with secondary ion-mass spectroscopy measurements. This diffusion could form a buried p–n junction, resulting in deteriorated device characteristics.

Metal nanoclusters, composed of tens to thousands of atoms, display the phenomenon of electronic shell structure. This quantum size effect, with its associated level degeneracy, turns out to be highly propitious for superconductivity. Spectroscopy of free aluminum nanoclusters has revealed a pairing phase transition in their electron density of states at a temperature two orders of magnitude higher than the bulk. In addition to gas-phase research on this new family of high-Tc systems, it is important to pursue their use as building blocks for superconducting networks and assemblies. The development of devices suitable for the detection of superconductivity in surface-deposited nanoclusters is outlined.

Metal-organic framework (MOF) films can be made by cathodic electrodeposition, where a Bronsted base is formed electrochemically which deprotonates the MOF linkers that are present in solution as undissociated/partially dissociated weak acids. However, the co-deposition of metal and the narrow range of possible metal nodes limit the scope of this method. In this work, we propose the use of hydrogen peroxide (hydrogen peroxide assisted cathodic deposition or HPACD), to overcome these limitations. Electrochemical measurements indicate that in DMF, hydrogen peroxide is reduced to superoxide anions that deprotonate the carboxylic ligands. This single-electron reduction happens at much higher potentials than all previous reported methods. This prevents the co-deposition of metal and extends the range of possible metal nodes. Various pure MOF films (HKUST-1, MIL-53(Fe) and MOF-5) were prepared via this approach. HPACD was also used for the preparation of patterned MOF films and of flexible Cu-BTC coated paper membranes which reject 99.1 % of Rose Bengal from water with a permeance of 8.4 L m-2 h-1 bar-1 .

All-solid-state lithium-metal batteries (ASSLMBs) have received great interest due to their high potential to display both high energy density and safety performance. However, the poor compatibility at the Li/solid electrolyte (SE) interface and penetration of lithium dendrites during cycling strongly impede their successful commercialization. Herein, a thin Ag layer was introduced between Li and Li10GeP2S12 for the in situ formation of a Li-Ag alloy interface, thus tuning the interfacial chemistry and lithium deposition/dissolution behavior. Superior electrochemical properties and improved interfacial stability were achieved by optimizing the Ag thicknesses. The assembled symmetric cell with Li@Ag 1 μm showed a steady voltage evolution up to 1000 h with an areal capacity of 1 mAh cm-2. Moreover, a high reversible capacity of 106.5 mAh g-1 was achieved in an all-solid-state cell after 100 cycles, demonstrating the validity of the Ag layer. This work highlights the importance of the Li/SE interface re-engineering and provides a new strategy for improving the cycle life of ASSLMBs.

As reported in previous studies, the processing of Mo–Si–B alloys using additive manufacturing (AM) techniques, like directed energy deposition (DED) shows a high technical feasibility. The present work investigates the cyclic oxidation performance of an AM DED Mo–9Si–8B alloy. Depending on the temperature (800 °C, 1100 °C, 1300 °C), the oxidation mechanisms vary, which is due to different reactions at the surface of the alloys accompanied with mass changes of samples. These mass changes can be explained on the basis of microstructural investigations. However, compared to a powder metallurgically processed Mo–9Si–8B alloy, the AM-DED alloy shows competitive oxidation performance at potential application temperatures of 1100 °C and 1300 °C, while a catastrophic materials degradation occurs at 800 °C as also observed in other Mo-rich Mo–Si–B alloys.

Silicon-based nanosheets were prepared by a topochemical method with four solvents of methanol, ethanol, isopropyl, and alcohol glycol. SNS prepared by methanol was decorated by Pd/Li particles with different ratios (6 wt%, 13 wt%, 20 wt%), respectively. The layers of Pd/Li deposition had a significant impact on the structure, micromorphology, and hydrogen storage performance of silicon-based nanosheets. The deposited Pd grains transformed from dispersion particles into aggregation with increasing the depositing. The hydrogen storage property of Pd/Li decorated silicon-based nanosheets enhances greatly compared with the original substrate. The Pd/Li decorated alloy with deposition ratio 13 wt% demonstrates high adsorption property of 4.5 wt% and superior hydriding kinetic property, which attribute to the existence of Pd/Li bringing relative moderate strong physical adsorption and the spillover mechanism of Pd/Li particles on substrate. In addition, it is found that the hydrogen storage mechanism of Pd/Li particles decorated on silicon-based nanosheets is related to electrostatic interaction induced by the strong local electric field. The Pd/Li-decorated SNS was obtained by Pd and Li particles uniformly distributed on the layered silicon nanosheets from CaSi2 by topological reaction.

This study illustrates the methodology used to evaluate wax deposition thickness. It presents a mathematical model to evaluate the petroleum deposition thickness and then it is validated by experim...

Ti–Al–V–Nb alloys with the cluster formula, 12[Al–Ti12](AlTi2)+5[Al–Ti14](V,Nb)2Ti, were designed by replacing V with Nb based on the Ti–6Al–4V alloy. Single-track cladding layers and bulk samples of the alloys with Nb contents ranging from 0 to 6.96 wt.% were prepared by laser additive manufacturing to examine their formability, microstructure, and mechanical properties. For single-track cladding layers, the addition of Nb increased the surface roughness slightly and decreased the molten pool height to improve its spreadability. The alloy, Ti–5.96Al–1.94V– 3.54Nb (wt.%), exhibited better geometrical accuracy than the other alloys because its molten pool height was consistent with the spread layer thickness of the powder. The microstructures of the bulk samples contained similar columnar β-phase grains, regardless of Nb content. These grains grew epitaxially from the Ti substrate along the deposition direction, with basket-weave α-phase laths within the columnar grains. The α-phase size increased with increasing Nb contents, but its uniformity decreased. Along the deposition direction, the Vickers hardness increased from the substrate to the surface. The Ti–5.96Al–1.94V–3.54Nb alloy exhibited the highest Vickers hardness regardless of deposition position because of the optimal matching relationship between the α-phase size and its content among the designed alloys.

Ultraviolet (UV) detector based on β-Ga2O3/p-GaN was fabricated in this paper. The growth process involved deposition of amorphous Ga2O3 layer by means of magnetron sputtering and conversion of β-Ga2O3. The obtained detector displays excellent UV sensing properties which covers Ultraviolet A(UVA)/Ultraviolet C(UVC) region with fast response. It will provide a new route to fabricate β-Ga2O3/p-GaN heterostructure for applications in broadband ultraviolet sensing.

In recent studies, porphyrin derivatives have been frequently used as building blocks for the fabrication of metal–organic coordination networks (MOCNs) on metal surfaces under ultrahigh vacuum conditions (UHV). The porphyrin core can host a variety of 3d transition metals, which are usually incorporated in solution. However, the replacement of a pre-existing metal atom in the porphyrin core by a different metallic species has been rarely reported under UHV. Herein, we studied the influence of cyanophenyl and pyridyl functional endgroups in the self-assembly of structurally different porphyrin-based MOCNs by the deposition of Fe atoms on tetracyanophenyl (Co-TCNPP) and tetrapyridyl-functionalized (Zn-TPPyP) porphyrins on Au(111) by means of scanning tunneling microscopy (STM). A comparative analysis of the influence of the cyano and pyridyl endgroups on the formation of different in-plane coordination motifs is performed. Each porphyrin derivative formed two structurally different Fe-coordinated MOCNs stabilized by three- and fourfold in-plane coordination nodes, respectively. Interestingly, the codeposited Fe atoms did not only bind to the functional endgroups but also reacted with the porphyrin core of the Zn-substituted porphyrin (Zn-TPyP), i.e., an atom exchange reaction took place in the porphyrin core where the codeposited Fe atoms replaced the Zn atoms. This was evidenced by the appearance of molecules with an enhanced (centered) STM contrast compared with the appearance of Zn-TPyP, which suggested the formation of a new molecular species, i.e., Fe-TPPyP. Furthermore, the porphyrin core of the Co-substituted porphyrin (Co-TCNPP) displayed an off-centered STM contrast after the deposition of Fe atoms, which was attributed to the binding of the Fe atoms on the top site of the Co-substituted porphyrin core. In summary, the deposition of metal atoms onto organic layers can steer the formation of structurally different MOCNs and may replace pre-existing metal atoms contained in the porphyrin core.

Though lithium metal has long been regarded as an ideal anode material for high-density batteries, the potential safety hazards greatly hampered its applications due to the non-uniform lithium nucleation and subsequent uncontrollable growth of lithium dendrites. To address these problems, herein, we developed carbon nanoribbons (LBCRs) with linearly distributed nucleation seeds and longitudinally bent structure. In the unique LBCRs, not only nucleation seeds located along edges decreased the nucleation barrier of lithium, inducing selective lithium nucleation, but also conductive carbon skeleton with bent structure regulated Li ion flux, preventing the formation of lithium dendrites. Moreover, LBCRs alleviated the volume change during cycling by guiding the lithium deposition inside the cavity. On the consequence, controllable lithium deposition was realized within LBCRs, and resulted composite anodes exhibited superior cycling stability including a low voltage hysteresis of 47.4 mV with a long cycle life over 700 h and a stable Coulombic efficiency above 94%.

Femtosecond laser induced periodic surface structures (LIPSSs) are excellent biomimetic iridescent antireflective interfaces. In this work, we demonstrate the feasibility to develop tunable iridescent antireflective surfaces via simultaneous synthesis of functional metal-oxide nanomaterials, in situ deposition and hierarchical LIPSSs nanostructuring by means of femtosecond laser ablation (fs-LA) of tungsten (W) and molybdenum (Mo) in air. Adjusting the scanning interval from 1 μm to 20 μm allows the modulation of particle deposition rates on LIPSSs. Diminishing the scan interval enables a higher particle deposition rate, which facilitates the development of better UV-to-MIR ultrabroadband antireflective surfaces with a less pronounced iridescence. Through comparing the reflectance of hierarchical LIPSSs with different densities of loosely/tightly deposited particles, it is found that the deposited WOx and MoOx particle aggregates have high UV-to-MIR ultrabroadband absorbance, especially extraordinary in the MIR range. Loosely deposited particles which self-assembly into macroporous structures outperform tightly deposited particles for ultrabroadband antireflective applications. The presence of loosely deposited MoOx and WOx particle absorbers can cause up to 80 % and 60 % enhancement of antireflectance performances as compared to the tightly particle deposited LIPSSs samples. One stone of “fs-LA technique” with three birds of (particle generation, in situ deposition and LIPSS hierarchical nanostructuring) presented in this work opens up new opportunities to tune the reflectance and iridescence of metallic surfaces.

Two new precursors for focused electron beam-induced deposition (FEBID) of cobalt silicides have been synthesized and evaluated. The H3SiCo(CO)4 and H2Si(Co(CO)4)2 single-source precursors retain the initial metal ratios and show low sensitivity to changes in the FEBID parameters such as acceleration voltage, beam current, and precursor pressure. The precursors allow the direct writing of material containing ∼55 to 60 at % total metal/metalloid content combined with high growth rates. During the deposition process an average of ∼80% of the carbonyl ligands are cleaved off in these planar deposits. Postgrowth electron curing does not change the deposits' composition, but resistivities decrease after the curing procedure. Temperature-dependent electrical properties indicate the presence of a granular metal for both cured samples and the as-grown Co2Si deposit, while the as-grown CoSi material is on the insulating side of the metal-insulator transition. The observed magnetoresistance behavior is indicative of tunneling magnetoresistance and is substantially reduced upon postgrowth irradiation treatment.

Antimony chalcogenides are widely studied as a light-absorbing material due to their merits of low toxicity, efficient cost, and excellent photovoltaic properties. However, the band gaps of antimony selenide (approximately 1.1 eV) and antimony sulfide (approximately 1.7 eV) both deviate from the optimal detailed balance band gap (∼1.3 eV) for terrestrial single-junction solar cells. Notably, the band gap of Sb2(S, Se)3 can be tunable in the range from 1.1 to 1.7 eV, which can cover the detailed balance band gap. In this work, the vapor transport deposition method with two independent evaporation sources is used to deposit Sb2(S, Se)3 thin films. By carefully optimizing the evaporation temperature and the start evaporation time of the Sb2Se3 and Sb2S3 sources, a suitable band gap of 1.33 eV is obtained. Finally, on the basis of the optimal Sb2(S, Se)3 films, Sb2(S, Se)3 solar cells without a hole transport layer achieved an efficiency of 7.03%.

Hydrothermal deposition is emerging as a highly potential route for antimony-based solar cells, in which the Sb2(S,Se)3 is typically in situ grown on a common toxic CdS buffer layer. The narrow band gap of CdS causes a considerable absorption in the short-wavelength region and then lowers the current density of the device. Herein, TiO2 is first evaluated as an alternative Cd-free buffer layer for hydrothermally derived Sb2S3 solar cells. But it suffers from a severely inhomogeneous Sb2S3 coverage, which is effectively eliminated by inserting a Zn(O,S) layer. The surface atom of sulfur in Zn(O,S) uniquely provides a chemical bridge to enable the quasi-epitaxial deposition of Sb2S3 thin film, confirming by both morphology and binding energy analysis using DFT. Then the results of the first-principles calculations also show that Zn(O,S)/Sb2S3 has a more stable structure than TiO2/Sb2S3. The resultant perfect Zn(O,S)/Sb2S3 junction, with a suitable band alignment and excellent interface contact, delivers a remarkably enhanced JSC and VOC for Sb2S3 solar cells. The device efficiency with the TiO2/Zn(O,S) buffer layer boosts from 0.54% to 3.70% compared with the counterpart of TiO2, which has a champion efficiency of Cd-free Sb2S3 solar cells with a structure of ITO/TiO2/Zn(O,S)/Sb2S3/Carbon/Ag by in situ hydrothermal deposition. This work provides a guideline for the hydrothermal deposition of antimony-based films upon a nontoxic buffer layer.