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[Display omitted] • Synthesis of melamine-phloroglucinol-formaldehyde (MPF) for N -doped porous carbon. • Catalyst materials possess hierarchical porous structure, high specific surface area. • MPF/M = Fe, Co catalysts show high ORR activity in 0.1 M KOH (E 1/2 up to 0.81 V) • M N C catalysts show excellent electrochemical stability for 10,000 potential cycles. • Excellent AEMFC performance (P max = 347, 324 mW cm−2) with MPF/Fe and MPF/Co catalysts. Delving into highly active and cost-efficient electrocatalysts for oxygen reduction reaction (ORR) is crucial for the large-scale application of polymer electrolyte fuel cells. Anion exchange membrane fuel cells (AEMFCs) are promising clean energy devices owing to their mild reaction conditions and the high probability of employing Pt-free catalysts for ORR. Developing the promising non-Pt ORR catalysts for AEMFC is still of great importance. Herein, we report the transition metal (Fe, Co, Mn, and Cu) impregnated melamine-phloroglucinol-formaldehyde (MPF) polymeric networks to derive metal-nitrogen-carbon (M N C) electrocatalysts via a robust synthesis route. The catalysts are screened through variable metal contents and different pyrolysis temperature optimizations by virtue of their ORR activity. The controlled synthesis method resulted to the prominent textural properties of the catalysts with efficient active centers to enhance the ORR performance. Amongst, iron-doped (MPF/Fe), and cobalt-doped (MPF/Co) catalysts are performing better in terms of half-wave potential (E 1/2) values of 0.81 and 0.80 V vs RHE which is attributed to the highly active M−N x sites and hierarchical porous structure of catalysts. Outstanding electrochemical stability in half-cell and high-power density in an AEMFC (up to 347 mW cm−2) made the present work drive to the development of highly efficient M N C catalysts for fuel cell applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ligand-enabled strategy for dual metal incorporation in MOF-derived bifunctional electrocatalysts. • Mixed-metal MOF (TAL-42) versatile starting material for efficient bifunctional electrocatalysts. • New synthetic protocol for highly active bimetallic materials. • Heterogeneous bimetallic surface with pyridinic & M-N x functionalities for excellent bifunctional performance. • TAL-42-900 air cathode in zinc-air battery shows excellent efficiency, no degradation over prolonged cycling. This work reports a novel ligand-enabled strategy to incorporate dual metals into metal–organic-framework-derived bifunctional oxygen electrocatalysts. The involvement of bimetallic systems helps to reduce the necessity for critical raw materials while enhancing the overall electroactivity of the catalyst. Herein, we introduce a unique mixed-metal manganese/cobalt metal–organic framework (TAL-42) as a versatile single precursor for the facile preparation of highly efficient bifunctional oxygen electrocatalysts. Rotating disk electrode (RDE) experiments in 0.1 M KOH demonstrated that forming the heterogeneous bimetallic surface with metal-N x functionalities results in an excellent bifunctional performance toward oxygen reduction/evolution reaction. The TAL-42–900 material exhibited superior bifunctional ORR/OER performance (ΔE = 0.80 V) to commercial Pt/C + RuO 2 catalyst (ΔE = 0.84 V). In a rechargeable zinc-air battery test, the TAL-42–900 air cathode possessed excellent efficiency with a maximum power density of 155 mW cm−2 without degradation over prolonged cycling. [ABSTRACT FROM AUTHOR]

• Ordered mesoporous carbon (OMC) with 7 nm pores made via green soft-templating route. • OMC, OMC/carbide-derived carbon and OMC/carbon nanotube composites act as supports. • 1,10-phenanthroline, Fe- and Co-acetates are used as doping agents in pyrolysis. • All CoFe-N-C catalysts show high ORR activity in alkaline media (E 1/2 = 0.84 V). • AEMFC performance depends on porous structure and CoFe-N-OMC/CNT is the best catalyst. Cobalt-, iron- and nitrogen-doped ordered mesoporous carbon (OMC)-based electrocatalysts are prepared, characterized, and used as cathode catalysts in anion-exchange membrane fuel cell (AEMFC). The OMC material is synthesized using a green and simple route via soft-template method and without the usage of harsh chemicals. To study the effect of porous structure of carbon support on the electrocatalytic properties, the OMC material is also mixed either with carbide-derived carbon (CDC) or carbon nanotubes (CNTs). Doping of carbon nanomaterials is done via high-temperature pyrolysis in the presence of cobalt and iron acetate as well as 1,10-phenanthroline. The physico-chemical characterization shows that the preparation of OMC and subsequent doping of nanocarbons has been successful, and the catalysts contain single-atom M-N x centres. The initial assessment employing the rotating disc electrode method indicates that all three doped catalyst materials exhibit very high electrocatalytic activity toward the oxygen reduction reaction (ORR) in alkaline media and good stability after 10,000 potential cycles. In AEMFC testing with AEMION+ anion exchange membrane, the prepared cathode catalysts show good performance with CoFe-N-OMC/CNT obtaining the highest peak power density of 336 mW cm–2. Slightly lower AEMFC performance observed for CoFe-N-OMC and CoFe-N-OMC/CDC cathodes indicates that it is influenced by the catalyst's porous structure. It can be concluded that the OMC-based materials are promising cathode catalysts for AEMFC application. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nitrogen, Co- and/or Fe-doped nanocarbons prepared from rapeseed press cake. • ORR activity of Fe-containing catalysts is close to that of Pt/C in 0.1 M KOH. • Inhibition of ORR by CN− ions shows the existence of MN x centres. • Catalysts show high methanol tolerance and good stability. • In AEMFC , P max = 131 mW cm−2 achieved with bimetallic catalyst. Transition metal-containing nitrogen-doped carbon catalysts for the electrochemical oxygen reduction reaction (ORR) were prepared from inexpensive biomass - rapeseed press cake; cobalt and/or iron salts and dicyandiamide were employed as metal and nitrogen sources. After acid treatment, the catalysts showed excellent electrocatalytic ORR activity in rotating disk electrode experiments in 0.1 M KOH solution, comparable to that of Pt/C (20 wt%) catalyst; good tolerance to methanol and high stability in short-time tests. The bimetallic catalyst displayed moderate performance as cathode material in anion exchange membrane fuel cell (AEMFC) test, by reaching the peak power density of 131 mW cm−2. [ABSTRACT FROM AUTHOR]

Silicon carbide nanopowder was coated with amorphous alumina by atomic layer deposition (ALD), using trimethylaluminium Al(CH 3 ) 3 (TMA) and water as precursors. The ALD experiments were carried out at 300 ° C, using variable cycle count or changing pulse times at constant cycle count. Depending on deposition conditions, hardness averaging at 14.8 GPa and corresponding reduced elastic modulus of 114 GPa were measured. Maximum hardness values and reduced moduli of elasticity reached 25–30 and 134–202 GPa, respectively, improving the mechanical properties of composites. Increased precursor flow had positive effect on mechanical properties – maximum values of hardness and elastic module reached 35–45 and 218–261 GPa, respectively. In the composites, the mechanical properties were improved compared to pure alumina films or silicon carbide and the brittleness characteristic of SiC particle tablets was decreased. [ABSTRACT FROM AUTHOR]

Growing SiO 2 layer by wet-chemical oxidation of Si surfaces before growth of another insulating film(s) is a used method to passivate Si interfaces in applications (e.g., solar cell, photodiode) at low temperatures (LT) below 450 °C. We report on potential of LT ultrahigh-vacuum (UHV) treatments combined with the wet-chemical oxidation, by investigating effects of LT-UHV oxidation after the wet-chemical growth of SiO 2 and before growing Al 2 O 3 film on top of SiO 2 /Si. This method modifies the SiO 2 /Si and is found to (i) decrease defect-level density, (ii) increase negative fixed charge density, and (iii) increase carrier lifetime for Al 2 O 3 /SiO 2 /p-Si, as compared to state-of-the-art SiO 2 /p-Si reference interfaces without LT-UHV. X-ray photoelectron spectroscopy shows that the LT-UHV treatment decreases amount of Si+3 oxidized atoms in chemically grown SiO 2 and also amount of carbon contamination. In order to pave the way for further tests of LT-UHV in silicon technology, we present a design of simple UHV instrument. The above-described benefits are reproduced for 4-inch silicon wafers by means of the instrument, which is further utilized to make LT-UHV treatments for complementary SiO 2 /Si interfaces of the native oxide at silicon diode sidewalls to decrease the reverse bias leakage current of the diodes. • Low-temperature passivation (<450 °C) of silicon interfaces is studied. • Chemically grown SiO 2 /Si has been tailored with ultrahigh-vacuum post treatments. • Decrease in interface defect density as compared to state-of-the-art reference. • Increase in carrier lifetime for p-Si at Al 2 O 3 /Si interfaces. [ABSTRACT FROM AUTHOR]

Resistive-switching Al 2 O 3 -doped TiO 2 thin films with thicknesses of around 10 nm were grown by atomic layer deposition, using TiCl 4 and Al(CH 3) 3 as the metal precursors and H 2 O as the oxygen source at 350 °C. A novel approach, based on the sequential pulsing of titanium and aluminum precursors, followed by a H 2 O pulse supplied only after the aluminum precursor pulse, was exploited to create diffuse Ti x Al 1–x O y layers in the TiO 2 host media, in order to tune the electrical properties. The films were deposited on substrates coated with conductive RuO 2 to promote the epitaxial growth of rutile-phase dielectric on the RuO 2 bottom electrode. Examination of the switching behavior confirmed the possibility to reduce the currents in the high resistance state, increase the difference between the high and low resistance states, and obtain multilevel resistive switching by adjusting the aluminum content and distribution in the films. [ABSTRACT FROM AUTHOR]

• BiPd and PbPd nanoalloy particles of about 3 nm in size are prepared in aqueous media. • Mass activity of BiPd/C for oxygen reduction is two-fold higher than that of Pd/C. • All the prepared alloy catalysts show excellent methanol tolerance in alkaline media. In this work three PdM/C bimetallic catalysts were prepared with a second metal being either Bi, Pb or Sn. The synthesised Pd-alloy nanoparticles were supported on Vulcan carbon XC-72R. These catalysts were studied using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), high resolution transmission electron microscopy (HR-TEM) and electrochemically using the rotating disk electrode (RDE) technique. The prepared Pd-based electrocatalysts were compared to pure Pd/C catalyst synthesised using the citrate method. The oxygen reduction reaction (ORR) kinetics on Pd-alloy catalysts in alkaline solution was systematically investigated. Pd content was determined by microwave plasma atomic emission spectroscopy, which was used to calculate the mass activities (MA) for ORR. Mass activities revealed that BiPd had two-fold higher and PbPd showed 1.6-times increase in MA as compared to Pd/C, however SnPd showed lower MA than Pd/C. BiPd/C catalyst showed around 45% increase in specific activity (SA) for ORR, PdSn catalyst showed around 25% increase and PbPd no increase in SA in comparison to the Pd/C catalyst. Methanol tolerance was also studied for the PdM/C alloy catalysts and a higher tolerance was observed for BiPd/C losing 17 mV in the half-wave potential value and even better methanol tolerance was in evidence with the other two catalysts that lost only ∼10 mV in 0.1 M KOH + 0.5 M MeOH. [ABSTRACT FROM AUTHOR]

Transition metal- and nitrogen-doped mesoporous carbons are prepared, characterised, and used as oxygen reduction reaction (ORR) electrocatalysts in an anion exchange membrane fuel cell (AEMFC). Novel mesoporous carbon (MPC) based engineered catalyst support is doped using high-temperature pyrolysis in the presence of metal acetate(s) and 1,10-phenanthroline (nitrogen source). Three transition metals are used to prepare materials with the following metal compositions: Fe, Co, CoFe, FeMn, and CoMn. Physico-chemical characterisation shows the success of doping with similar morphology and textural properties of all materials. The rotating ring-disc electrode experiments in alkaline solution show that all five catalysts exhibit good electrocatalytic activity towards the ORR, with Fe-N-MPC, CoFe-N-MPC and FeMn-N-MPC being best-performing materials with excellent stability. The HO 2 – yield depends on the metal composition with Fe-N-MPC and FeMn-N-MPC giving the lowest percentage. The latter two are employed in the AEMFC and reach power densities of 473 and 474 mW cm–2, respectively. [Display omitted] • Mesoporous Engineered Catalyst Support (Pajarito Powder) as base for five catalysts. • 1,10-phenanthroline and Fe-, Co-, and/or Mn-acetates as doping agents in pyrolysis. • M-N-MPC catalysts show high ORR activity in alkaline media (E 1/2 up to 0.9 V). • RRDE experiments revealed low peroxide yield on Fe-containing catalysts. • Excellent AEMFC performance (P max =470 mW cm–2) of Fe-N-MPC and FeMn-N-MPC catalysts. [ABSTRACT FROM AUTHOR]

Atomic layer deposition of ZrO2 films from tris(dimethylamino)cyclopentadienylzirconium CpZr(NMe2)3 and H2O, was investigated using real-time characterization of the growth process and post-growth measurements of the films. Self-limited nature of the deposition process was observed at substrate temperatures ranging from 120 to 350 °C. In this temperature range growth rate of 0.08-0.1 nm per cycle was obtained on silicon substrates. The films deposited on silicon substrates at 200 °C and higher temperatures contained tetragonal and monoclinic phases of ZrO2. The phase composition of the films depended on the deposition temperature as well as on the film thickness. The concentration of carbon residues decreased with increasing deposition temperature and did not exceed 0.9 at.% in the films deposited at 250 °C and higher temperatures. The refractive indices and densities of films grown from CpZr(NMe2)3 and H2O at 250-350 °C ranged from 2.15 to 2.20 (at a wavelength of 633 nm) and 5.6 to 6.0 g/cm³, respectively, being close to the highest values obtained for films deposited from ZrCl4 and H2O. The former process ensured, however, more uniform nucleation of ZrO2 on graphene than the latter process did. [ABSTRACT FROM AUTHOR]

Thin solid holmium titanium oxide films were grown by atomic layer deposition at 300 °C on silicon substrates. The precursors used were Ho(thd)3, Ti(OCH(CH3)2)4 and O3. The composition of the films was varied via changing the holmium-titanium ratio by variation of relative amounts of the sequential deposition cycles of constituent oxides, i.e. Ho2O3 and TiO2. The constituent oxides alone were crystallized in as-deposited states. After mixing the Ho2O3 or TiO2 layers the films were amorphous but were crystallized after annealing at 800-1000 °C, mostly transforming into the Ho2Ti2O7 phase. The stoichiometric ratio of 1:1 between Ti and Ho contents was achieved by application of at least twice as many Ho2O3 deposition cycles as TiO2 cycles. Magnetometry revealed that saturation magnetization could be observed in the films containing lower amounts of holmium compared to titanium. [ABSTRACT FROM AUTHOR]

Nanolaminate (nanomultilayer) thin films of TiO2 and Ho2O3 were grown on Si(001) substrates by atomic layer deposition at 300 °C from alkoxide and β-diketonate based metal precursors and ozone. Individual layer thicknesses were 2 nm for TiO2 and 4.5 nm for Ho2O3. As-deposited films were smooth and X-ray amorphous. After annealing at 800 °C and higher temperatures the nanolaminate structure was destroyed by solid-state reaction to form Ho2Ti2O7. The films demonstrated diamagnetic or paramagnetic behaviour in the as-deposited state. After annealing, the films possessed net magnetic moment, allowing one to record saturation magnetization and weak coercivity. =abstract= [ABSTRACT FROM AUTHOR]

A new platinum group metal (PGM)-free proton exchange membrane fuel cell (PEMFC) cathode catalyst materials, synthesized using the VariPore™ method by Pajarito Powder, LLC, are characterized for their structure and activity. The physico-chemical analysis of the iron-nitrogen-carbon (Fe-N-C) electrocatalysts show mesoporous carbon material effectively doped with iron and nitrogen. The materials have an average pore size of 7–8 nm and high specific surface area. The Fe-N-C catalysts exhibit good oxygen reduction reaction (ORR) activity in 0.5 M H 2 SO 4 electrolyte with high half-wave potential and sustainable electrochemical stability over 10,000 repeated potential cycles with insignificant losses in their activities. As cathode catalysts in a PEMFC, the Fe-N-C materials deliver remarkably good fuel cell performance at low overpotential approaching that of the commercial Pt catalyst. The high ORR electrocatalytic activity of these Fe-N-C catalysts is credited to the synergy between nitrogen-moieties, specifically pyrrolic-N, pyridinic-N, and graphitic-N, and iron in addition to the high mesoporosity that facilitate an effective reaction path in boosting the electrocatalytic activity and stability. [Display omitted] • State-of-the-art commercial PGM-free catalysts for ORR were characterized and evaluated. • Was shown that active centres are atomically dispersed. • Performance of electrocatalysts was evaluated in industrially manufactured MEA form-factor. • The fuel cell performance is close to the state-of-the-art R&D PGM-free catalysts. [ABSTRACT FROM AUTHOR]

• Pd nanoparticles supported on mesoporous N-doped carbon are compared with Pd/Vulcan. • A characterisation of the catalysts by TEM, BET, XRD, XPS, EDX and Raman analysis. • These catalysts are used for oxygen reduction reaction in acid and alkaline media. • Excellent oxygen reduction reaction activity was observed for all Pd-based catalysts. • Pd catalyst on mesoporous carbon support outperformed Pd/Vulcan in an AEMFC test. In this work three mesoporous nitrogen-doped carbon support materials were evaluated for oxygen reduction reaction (ORR) in comparison to Vulcan carbon in 0.1 M KOH and 0.5 M H 2 SO 4 solutions. Palladium nanoparticles were synthesised using citrate method and the average particle size of 3.9 ± 0.6 nm was obtained, which was determined from transmission electron microscopy (TEM) images. Unique porosities of these mesoporous engineered catalyst supports (ECS) were evaluated using the BET method and all of the materials displayed similar microporosity, altrough mesopore distribution varied greatly between these materials. Three different loadings of the Pd catalyst were applied to the support materials (varying between 20-40 wt% of Pd) to evaluate the support ability to disperse a large amount of Pd. By comparing the 40 wt% Pd loaded ECS-003604 and Vulcan XC-72R it can be noted that the Vulcan carbon-supported Pd catalyst is more agglomerated. The agglomeration of this catalyst is also noticeable from cyclic voltammetry (CV) studies, where the PdO reduction peak shifts to more positive values as compared to the mesoporous Pd/C counterparts. The ORR kinetics were explored using the rotating disc electrode (RDE) method. In acidic media a Pd catalyst supported on a bimodal mesoporous ECS material showed highest specific activity for oxygen electroreduction, while in alkaline the activity difference is less noticeable between the Pd-based electrocatalyst materials. One of the mesoporous N-doped carbon supported Pd catalyst was also compared to Pd/Vulcan cathode in single-cell alkaline anion exchange membrane fuel cell and improved peak power density was observed. [ABSTRACT FROM AUTHOR]

• Acid-treated CNTs were coated with SnO 2 by chemical method. • Platinum was photo-deposited on CNTs and SnO 2 -CNT supports. • Surface morphology was investigated by SEM and HAADF-STEM. • Pt/CNT and Pt/SnO 2 -CNT showed high oxygen reduction activity in acid media. Platinum nanoparticles were photo-deposited on acid-treated multi-walled carbon nanotubes (CNTs) and SnO 2 -coated CNTs. The SnO 2 -CNT nanocomposite was synthesised by a chemical method. Scanning and scanning transmission electron microscopy results indicated that the CNTs surface is partially covered by the SnO 2 layer. The surface morphology of the Pt catalyst depends on the nature of the support material. For instance, porous Pt aggregates of various sizes are formed at specific nucleation sites on the CNT surface, while a selective deposition of Pt was observed on the metal oxide part of the SnO 2 -CNT. Cyclic voltammetry and CO stripping investigations in 0.1 M HClO 4 solution confirmed different surface electrochemistry of the Pt catalysts. It is revealed that photo-deposition induces the formation of Pt-Sn nanoalloys due to increased interaction at the oxide interfaces. Both Pt/CNT and Pt/SnO 2 -CNT catalysts showed remarkable activity towards the electroreduction of oxygen in acid media. Durability measurement showed that photo-deposited Pt nanoparticles are more resistant to degradation. The corrosion-resistant nature of the SnO 2 -CNT support further improves the catalysts stability. Pt/CNT and Pt/SnO 2 -CNT catalysts retained 86% and 88% of the initial surface area respectively, after 10,000 potential cycles between 0.6 and 1.2 V RHE. [ABSTRACT FROM AUTHOR]

Atomic layer deposition was used to produce 90–105 nm thick alumina-zirconia mixtures and nanolaminate structures on soda-lime glass substrate. The resultant chemical and structural compositions of the thin films were characterized. Hardness and modulus of elasticity were determined by instrumented nanoindentation. The hardness of mixtures and nanolaminates were in the range of 11–15 GPa and moduli in the range of 140–180 GPa ZrO 2 with 3.7 mol.-% Al 2 O 3 crystallized in pure tetragonal phase and measured hardness reached about 15 GPa on glass substrate at indentation displacement of about 13 nm. Similar mechanical properties were measured in most thin films, except pure ZrO 2 , demonstrating insensitivity of mechanical properties to deposition receipt. • The hardness's were in the range of 11–15 GPa and moduli 140–180 GPa. • ZrO 2 alternated or doped with Al 2 O 3 layers stabilized mostly in tetragonal phase. • 3.7 mol.-% of Al was needed to stabilize pure tetragonal ZrO 2. • The hardness and moduli were insensitive to nanolaminate structure in some cases. [ABSTRACT FROM AUTHOR]

Dental and orthopedic implants have become routine medical technologies for tooth replacement and bone fixation. Despite significant progress in implantology, achieving sufficient osseointegration remains a challenge, often leading to implant failure over the long term. Nanotechnology offers the potential to mimic the natural patterns of living tissues, providing a promising platform for tissue engineering and implant surface design. Among the various methods for developing nanostructures, High-Regular Laser-Induced Periodic Surface Structures (HR-LIPSS) techniques stand out for their ability to fabricate highly ordered nanostructures with excellent long-range repeatability and production efficiency. In this study, we utilized an innovative technical approach to generate traditional laser-induced superficial LIPSS nanostructures, followed by detailed surface analysis using classical microscopy and physicochemical methods. Our findings demonstrate for the first time that nanostructured LIPSS surfaces can significantly enhance cell adhesion and proliferation while providing an optimal environment for cell metabolism. Given the high reproducibility, low cost, and potential of HR-LIPSS techniques to support cell growth and differentiation, this novel technology has the potential to impact both the industrial development of new implants and clinical outcomes after implantation., Competing Interests: Declaration of competing interest All authors declare that they have no conflicts of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Axial resolution is one of the most important characteristics of a microscope. In all microscopes, a high axial resolution is desired in order to discriminate information efficiently along the longitudinal direction. However, when studying thick samples that do not contain laterally overlapping information, a low axial resolution is desirable, as information from multiple planes can be recorded simultaneously from a single camera shot instead of plane-by-plane mechanical refocusing. In this study, we increased the focal depth of an infrared microscope non-invasively by introducing a binary axicon fabricated on a barium fluoride substrate close to the sample. Preliminary results of imaging the thick and sparse silk fibers showed an improved focal depth with a slight decrease in lateral resolution and an increase in background noise.

Polycrystalline SnO 2 thin films were grown by atomic layer deposition (ALD) on SiO 2 /Si(100) substrates from SnI 4 and O 3 . Suitable evaporation temperatures for the SnI 4 precursor as well as the relationship between growth per cycle and substrate temperature were determined. Crystal growth in the films in the temperature range of 225-600 °C was identified. Spectroscopic analyses revealed low amounts of residual iodine and implied the formation of single-phase oxide in the films grown at temperatures above 300 °C. Appropriateness of the mentioned precursor system to the preparation of SnO 2 films was established., (Copyright © 2023, Kalam et al.)

The rapidly expanding demand for photovoltaics (PVs) requires stable, quick, and easy to manufacture solar cells based on socioeconomically and ecologically viable earth-abundant resources. Sb 2 S 3 has been a potential candidate for solar PVs and the efficiency of planar Sb 2 S 3 thin-film solar cells has witnessed a reasonable rise from 5.77% in 2014 to 8% in 2022. Herein, the aim is to bring new insight into Sb 2 S 3 solar cell research by investigating how the bulk and surface properties of the Sb 2 S 3 absorber and the current-voltage and deep-level defect characteristics of solar cells based on these films are affected by the ultrasonic spray pyrolysis deposition temperature and the molar ratio of thiourea to SbEX in solution. The properties of the Sb 2 S 3 absorber are characterized by bulk- and surface-sensitive methods. Solar cells are characterized by temperature-dependent current-voltage, external quantum efficiency, and deep-level transient spectroscopy measurements. In this paper, the first thin-film solar cells based on a planar Sb 2 S 3 absorber grown from antimony ethyl xanthate (SbEX) by ultrasonic spray pyrolysis in air are demonstrated. Devices based on the Sb 2 S 3 absorber grown at 200 °C, especially from a solution of thiourea and SbEX in a molar ratio of 4.5, perform the best by virtue of suppressed surface oxidation of Sb 2 S 3 , favorable band alignment, Sb-vacancy concentration, a continuous film morphology, and a suitable film thickness of 75 nm, achieving up to 4.1% power conversion efficiency, which is the best efficiency to date for planar Sb 2 S 3 solar cells grown from xanthate-based precursors. Our findings highlight the importance of developing synthesis conditions to achieve the best solar cell device performance for an Sb 2 S 3 absorber layer pertaining to the chosen deposition method, experimental setup, and precursors.

Interferenceless coded aperture correlation holography (I-COACH) is one of the simplest incoherent holography techniques. In I-COACH, the light from an object is modulated by a coded mask, and the resulting intensity distribution is recorded. The 3D image of the object is reconstructed by processing the object intensity distribution with the pre-recorded 3D point spread intensity distributions. The first version of I-COACH was implemented using a scattering phase mask, which makes its implementation challenging in light-sensitive experiments. The I-COACH technique gradually evolved with the advancement in the engineering of coded phase masks that retain randomness but improve the concentration of light in smaller areas in the image sensor. In this direction, I-COACH was demonstrated using weakly scattered intensity patterns, dot patterns and recently using accelerating Airy patterns, and the case with accelerating Airy patterns exhibited the highest SNR. In this study, we propose and demonstrate I-COACH with an ensemble of self-rotating beams. Unlike accelerating Airy beams, self-rotating beams exhibit a better energy concentration. In the case of self-rotating beams, the uniqueness of the intensity distributions with depth is attributed to the rotation of the intensity pattern as opposed to the shifts of the Airy patterns, making the intensity distribution stable along depths. A significant improvement in SNR was observed in optical experiments.

Rechargeable zinc-air batteries (RZAB) have gained significant attention as potential energy storage devices due to their high energy density, cost-effectiveness, and to the fact that they are environmentally safe. However, the practical implementation of RZABs has been impeded by challenges such as sluggish oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), including poor cyclability. Herein, we report the preparation of cobalt- and nitrogen-doped porous carbon derived from phloroglucinol-formaldehyde polymer networks with 2-methyl imidazole and cobalt phthalocyanine as precursors for nitrogen and cobalt. The CoN-PC-2 catalyst prepared in this study exhibits commendable electrocatalytic activity for both ORR and OER, evidenced by a half-wave potential of 0.81 V and E j=10 of 1.70 V. Moreover, the catalyst demonstrates outstanding performance in zinc-air batteries, achieving a peak power density of 158 mW cm -2 and displaying excellent stability during charge-discharge cycles. The findings from this study aim to provide valuable insights and guidelines for further research and the development of hierarchical micro-mesoporous carbon materials from polymer networks, facilitating their potential commercialisation and widespread deployment in energy storage applications.

The goal of achieving the large-scale production of zero-emission vehicles by 2035 will create high expectations for electric vehicle (EV) development and availability. Currently, a major problem is the lack of suitable batteries and battery materials in large quantities. The rechargeable zinc-air battery (RZAB) is a promising energy-storage technology for EVs due to the environmental friendliness and low production cost. Herein, iron, cobalt, and nickel phthalocyanine tri-doped electrospun carbon nanofibre-based (FeCoNi-CNF) catalyst material is presented as an affordable and promising alternative to Pt-group metal (PGM)-based catalyst. The FeCoNi-CNF-coated glassy carbon electrode showed an oxygen reduction reaction/oxygen evolution reaction reversibility of 0.89 V in 0.1 M KOH solution. In RZAB, the maximum discharge power density ( P max ) of 120 mW cm -2 was obtained with FeCoNi-CNF, which is 86% of the P max measured with the PGM-based catalyst. Furthermore, during the RZAB charge-discharge cycling, the FeCoNi-CNF air electrode was found to be superior to the commercial PGM electrocatalyst in terms of operational durability and at least two times higher total life-time.

Coatings with tunable refractive index and high mechanical resilience are useful in optical systems. In this work, thin films of HfO 2 doped with Al 2 O 3 were deposited on silicon at 300 °C by using plasma-enhanced atomic layer deposition (PE-ALD). The mainly amorphous 60-80 nm thick films consisted Al in the range of 2 to 26 at.%. The refractive indexes varied from 1.69 to 2.08 at the wavelength of 632 nm, and they consistently depended on the composition. The differences were higher in the UV spectral region. At the same time, the hardness of the films was from 12-15 GPa; the modulus was in the range of 160-180 GPa; and the mechanical properties did not have a good correlation with the deposited compositions. The deposition conditions, element contents, and refractive indexes at respective wavelengths were correlated. The results indicated that it is possible to tune optical properties and retain mechanical properties of atomic layer-deposited thin films of HfO 2 with Al 2 O 3 as doping oxide. Such films could be used as mechanically resilient and optically tunable coatings in, for instance, micro- or nano-electromechanical systems or transparent displays.

Fresnel incoherent correlation holography (FINCH) is a well-established incoherent digital holography technique. In FINCH, light from an object point splits into two, differently modulated using two diffractive lenses with different focal distances and interfered to form a self-interference hologram. The hologram numerically back propagates to reconstruct the image of the object at different depths. FINCH, in the inline configuration, requires at least three camera shots with different phase shifts between the two interfering beams followed by superposition to obtain a complex hologram that can be used to reconstruct an object's image without the twin image and bias terms. In general, FINCH is implemented using an active device, such as a spatial light modulator, to display the diffractive lenses. The first version of FINCH used a phase mask generated by random multiplexing of two diffractive lenses, which resulted in high reconstruction noise. Therefore, a polarization multiplexing method was later developed to suppress the reconstruction noise at the expense of some power loss. In this study, a novel computational algorithm based on the Gerchberg-Saxton algorithm (GSA) called transport of amplitude into phase (TAP-GSA) was developed for FINCH to design multiplexed phase masks with high light throughput and low reconstruction noise. The simulation and optical experiments demonstrate a power efficiency improvement of ~ 150 and ~ 200% in the new method in comparison to random multiplexing and polarization multiplexing, respectively. The SNR of the proposed method is better than that of random multiplexing in all tested cases but lower than that of the polarization multiplexing method., (© 2023. The Author(s).)

Mechanical properties of thin films are significant for the applicability of nanodevices. Amorphous Al 2 O 3 -Ta 2 O 5 double and triple layers were atomic layer-deposited to the thickness of 70 nm with constituent single-layer thicknesses varying from 40 to 23 nm. The sequence of layers was alternated and rapid thermal annealing (700 and 800 °C) was implemented on all deposited nanolaminates. Annealing caused changes in the microstructure of laminates dependent on their layered structure. Various shapes of crystalline grains of orthorhombic Ta 2 O 5 were formed. Annealing at 800 °C resulted in hardening up to 16 GPa (~11 GPa prior to annealing) in double-layered laminate with top Ta 2 O 5 and bottom Al 2 O 3 layers, while the hardness of all other laminates remained below 15 GPa. The elastic modulus of annealed laminates depended on the sequence of layers and reached up to 169 GPa. The layered structure of the laminate had a significant influence on the mechanical behavior after annealing treatments.

SiO 2 films were grown to thicknesses below 15 nm by ozone-assisted atomic layer deposition. The graphene was a chemical vapor deposited on copper foil and transferred wet-chemically to the SiO 2 films. On the top of the graphene layer, either continuous HfO 2 or SiO 2 films were grown by plasma-assisted atomic layer deposition or by electron beam evaporation, respectively. Micro-Raman spectroscopy confirmed the integrity of the graphene after the deposition processes of both the HfO 2 and SiO 2 . Stacked nanostructures with graphene layers intermediating the SiO 2 and either the SiO 2 or HfO 2 insulator layers were devised as the resistive switching media between the top Ti and bottom TiN electrodes. The behavior of the devices was studied comparatively with and without graphene interlayers. The switching processes were attained in the devices supplied with graphene interlayers, whereas in the media consisting of the SiO 2 -HfO 2 double layers only, the switching effect was not observed. In addition, the endurance characteristics were improved after the insertion of graphene between the wide band gap dielectric layers. Pre-annealing the Si/TiN/SiO 2 substrates before transferring the graphene further improved the performance.

Thin solid films consisting of ZrO 2 and Fe 2 O 3 were grown by atomic layer deposition (ALD) at 400 °C. Metastable phases of ZrO 2 were stabilized by Fe 2 O 3 doping. The number of alternating ZrO 2 and Fe 2 O 3 deposition cycles were varied in order to achieve films with different cation ratios. The influence of annealing on the composition and structure of the thin films was investigated. Additionally, the influence of composition and structure on electrical and magnetic properties was studied. Several samples exhibited a measurable saturation magnetization and most of the samples exhibited a charge polarization. Both phenomena were observed in the sample with a Zr/Fe atomic ratio of 2.0.

Colorimetric gas sensing is demonstrated by thin films based on ultrasmall TiO 2 nanoparticles (NPs) on Si substrates. The NPs are bound into the film by p -toluenesulfonic acid (PTSA) and the film is made to absorb volatile organic compounds (VOCs). Since the color of the sensing element depends on the interference of reflected light from the surface of the film and from the film/silicon substrate interface, colorimetric detection is possible by the varying thickness of the NP-based film. Indeed, VOC absorption causes significant swelling of the film. Thus, the optical path length is increased, interference wavelengths are shifted and the refractive index of the film is decreased. This causes a change of color of the sensor element visible by the naked eye. The color response is rapid and changes reversibly within seconds of exposure. The sensing element is extremely simple and cheap, and can be fabricated by common coating processes.