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This study investigates changes in the charge transfer resistance (R ct ) and diffusion impedance (Z w ) according to the thickness of a CNT/Pt layer coated onto an FTO glass counter electrode (CE) to improve the photovoltaic performance of dye-sensitized solar cells (DSCs). For this purpose, we carefully controlled the thickness of the CE by using different amounts of CNT/Pt in the paste. Note that both R ct and Z w decrease with an increase in the thickness of the CEs. Power conversion efficiencies of 7.77, 8.21, 7.58 and 7.36% are determined for DSCs with thicknesses of the CNT/Pt layer of 1, 3.2, 10 and 18 μm, respectively. The obtained results are in good agreement with the changes in the ratio of R ct /Z w . When the ratio of R ct /Z w becomes one and the R ct value is less than 1 Ωcm 2 , the device shows the best performance. Because this strategy is simple and effective, it can be useful for developing cost-effective CE materials for DSCs. [ABSTRACT FROM AUTHOR]

Abstract: This study reports the fabrication of a Petri dish patterned with cylindrical micro‐cavities that are produced using a one‐step solvent‐immersion phase‐separation process. The developed 3D honeycomb Petri dish is coated with a Au film through a sputtering method to be an efficient Au‐coated FTO‐free electrode for quantum‐dot‐sensitized solar cells. Due to the high specific active surface area of the electrode with the Au‐coated honeycomb structure, the energy conversion efficiency of devices that use this electrode is 5.2 % compared to 4.4 and 4.7 % by devices using an Au‐coated flat Petri dish and an Au‐coated FTO electrode, respectively. This design strategy offers excellent potential for the fabrication of highly efficient counter electrodes with FTO‐free substrates of flexible photovoltaic devices. [ABSTRACT FROM AUTHOR]

In this work, control of the surface morphology and the wettability of polymer substrates is demonstrated using a simple one-step process. The approach is based on combining the nonsolvent-induced phase separation and a scalable dip-coating technique. Two types of solvent/nonsolvent systems, i.e. water-immiscible and water-miscible mixtures, are used to not only induce an outermost ternary solution but also produce and control the porous structure on the substrate surface through the phase separation and self-assembly of the nonsolvent-rich templating droplets. The effects of the solvent systems and their compositions on the surface features, cross-sectional morphology, and wettability are systematically investigated and compared. Furthermore, a potential mechanism for the formation of a ternary solution resulting in the micropore structure on the poly(methyl methacrylate) (PMMA) substrate surface is proposed. [ABSTRACT FROM AUTHOR]

Abstract: Remarkable morphology of platinum (Pt) nanostructures from submicron clusters, by way of nanoclusters, to nanoparticles (NPs) was obtained through controlling the heating rate of thermo-decomposition of Pt precursor molecules. Uniform and dense distribution of Pt-NPs was obtained on FTO glass substrate prepared at the heating rate lower than 1.2°Cmin−1. The highest electrocatalytic performance, which corresponded to the lowest charge transfer resistance of 0.86Ω cm2, was achieved with the counter electrode prepared at the heating rate of 1.2°Cmin−1 during sintering. The heating rate during sintering proved to be a sensitive parameter for determining the morphology of Pt-NPs formed on the surface of FTO glass substrate, which subsequently influenced the catalytic activity of the Pt-NPs and subsequently the photovoltaic performance of a dye-sensitized solar cell (DSC). The highest conversion efficiency of the DSC prepared with the heating rate of 1.2°Cmin−1 was 9.30% with fill factor of 67.21%, J sc of 18.14mAcm−2, and V oc of 762.5mV. [Copyright &y& Elsevier]

Abstract: This study modified the surface of polyvinylidene fluoride (PVDF) films and characterized their surface physicochemical properties. The main aim of this study was to examine how to provide the surface with a specific property, e.g., not only hydrophobic but also oleophobic (amphiphobicity) after argon atmospheric pressure plasma (APP) treatment. The surface free energy calculated using the Owens–Wendt (OW) method decreased significantly while showing a very small value of the polar component. Scanning electron microscopy indicated that a small amount of hydrophilic solid spines and many superamphiphobic uniform micro air pockets formed in the plasma-modified PVDF film, which made it amphiphobic but not superamphiphobic. [Copyright &y& Elsevier]

Abstract: Ar atmospheric pressure plasma (APP) was used to treat indium-tin-oxide (ITO). The plasma conditions were varied to treat the ITO surface, e.g., plasma treatment time, RF power, flow rate, and the plasma outlet-to-sample distance. The plasma effectiveness was measured by the contact angle. The change in the surface energy calculated with the Owens–Wendt method mainly arises from the polar component. The dynamic contact angle measurements show that APP-treated surface showed considerably lower hysteresis in the water and ethylene glycol but there was no change in hysteresis in methylene iodide compared with the untreated ITO. Atomic force microscopy showed that the Ar APP-treated surface sharply decreased the surface roughness and showed a similar morphology as the untreated ITO. X-ray photoelectron spectroscopy showed that the Ar APP treatment not only effectively removed carbon contamination from the surface but also introduced oxygen. Therefore, it is believed that the APP treatment modifies the physico-chemical properties of ITO, which can in turn improve the performance of the organic light-emitting diodes. [Copyright &y& Elsevier]

Abstract: This study compared the effects of Ar/O2 and He/O2 plasma on the photoresist (PR) removal of a silicon wafer under a pressure of one atmosphere. In the atmospheric pressure plasma, the Ar-plasma-treated surface had a higher surface energy and was more hydrophilic than the He-plasma-treated surface. The density of the active species in the Ar/O2 plasma was much larger than that in the He/O2 plasma. Therefore, an Ar/O2 plasma discharge is much more efficient in etching a PR than a He/O2 plasma. The PR etch rate was measured as a function of the nozzle to sample distance and the feed flow rate, as well as the radio frequency (RF) power and additive gas(O2) flow rate. In these experiments, a maximum etch rate was about to 190 nm/min at an RF power of 120 W, Ar/O2 flow rates of 8 slm/70 sccm, and a treatment time of 3 min. The surface of the etched PR was characterized using atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). AFM showed that the etch reaction of the Ar/O2 plasma occurs via sputter etching and that of the He/O2 plasma occurs via chemical reaction. From the XPS results, it is concluded that the Ar/O2 plasma effectively removes the carbon component from the PR coated surface. [Copyright &y& Elsevier]

We introduced carboxylic groups on the surface of polyurethane (PU) with the aid of oxygen plasma treatment and the post-grafting of acrylic acid (AAc) in an aqueous solution. After plasma treatment, PU was exposed to the air to generate peroxides. Peroxides were confirmed by the 1,1-diphenyl-2-picrylhydrazyl method. We chose different parameters of plasma treatment to get the optimum condition for introducing maximum peroxides on the surface. Peroxides are known to be the species responsible for initiating the graft co-polymerization when PU reacts with AAc to produce AAc grafted PU. The AAc grafted on the surfaces was characterized by water contact angle measurement, Fourier transform infrared by attenuated total reflectance and electron spectroscopy for chemical analysis and optical microscopy. After confirming a successful grafting of AAc, we studied the effect of reaction temperature, reaction time, monomer concentration and Mohr''s salt on the grafting degree of AAc. [Copyright &y& Elsevier]

Incorporating noble‐metal plasmonic nanoparticles (NPs) enhances the optoelectronic properties of perovskite solar cells (PSCs) but at a higher cost. In this work, the overlooked potential of refractory plasmonic materials is highlighted as a cost‐effective alternative additive in PSC research. This investigation aims to stimulate interest in this area by showcasing the theoretical and practical impacts of TiN plasmonic NPs when integrated into PSCs. TiN plasmonic NPs present a cost‐effective yet underexplored option. This study explores the impact of TiN NPs on PSCs through theoretical and experimental approaches. Finite‐difference time‐domain (FDTD) optical simulations and empirical data indicate that TiN NPs increase absorption and reduce reflectance in PSCs, driven by surface plasmon resonance and the significant growth of perovskite grains from 450 to 1400 nm. These NPs also regulate the perovskite crystallization rate by adsorbing DMF/DMSO, fostering larger grain formation. Improved band alignment and decreased trap states enhance charge transport and diminish non‐radiative recombination losses. As a result, PSC efficiency with optimal TiN NP concentration increased from 19.07% to 21.37%. Additionally, TiN‐enhanced PSCs display better stability, retaining 98.1% of their original PCE after 31 days under ambient conditions. [ABSTRACT FROM AUTHOR]

Oxygen evolution reaction (OER), an important reaction involved in water splitting and rechargeable batteries, has drawn massive attention to clean energy generation, conversion, and efficient storage technologies during the last decades. However, noble metal-based highly active electrocatalysts for OER have been employed for water splitting, whereas their excessive cost and lethargic kinetics impede their usage. Bimetallic nanoparticles (NPs) have appeared as an essential class of catalysts suggesting higher catalytic efficiencies. Nickel/Iron (NiFe)-based compounds have been known as active OER catalysts by enormous commercial interest owing to their interesting mechanical, electrical, and corrosion-resistant properties. In this study, we prepared various Ni x Fe y nanoporous by reducing Ni and Fe precursors using a NaBH 4 reducing agent. The obtained catalysts show the high BET surface areas of 108.18, 122.67, 157.14, 166.65, and 244.12 (m2/g) for Ni, Ni 3 Fe 1 , Ni 1 Fe 1 , Ni 1 Fe 3 , and Fe samples; respectively. Among synthesized catalysts, it is obvious that Ni 3 Fe 1 exhibits a good OER performance with an overpotential of 220 mV or 346 mV at a current density of 10 mA. cm−2 or 50 mA. cm−2 and stability for 60,000 s due to the interaction between Ni and Fe and the exposure of more active surface area and low charge transfer electron resistance of the catalyst. This cheap and highly efficient Ni 3 Fe 1 electrocatalyst can be a promising candidate for the OER in water splitting for producing green fuel hydrogen. [Display omitted] • NiFe nanoporous materials are synthesized with large BET surface areas. • The presence of Fe enhances the BET surface area in bimetallic NiFe materials compared to pure Ni. • Electron density transfer between Ni and Fe atoms on the surface of the catalyst improves the OER activity. • Ni 3 Fe 1 shows the best OER activity during long-time operation. [ABSTRACT FROM AUTHOR]

Dry plasma reduction (DPR) is an excellent approach for easily and uniformly immobilizing many platinum nanoparticles (Pt-NPs) with a size of 2–3 nm on both inner and outer surfaces of MWNTs under atmospheric pressure and at near room temperature. The MWNT–Pt nanohybrid exhibits quite low charge transfer resistance for dye-sensitized solar cells. [ABSTRACT FROM AUTHOR]

Abstract: A new counter electrode, which was simply fabricated with enlarging Pt-sputtered area, showed the energy conversion efficiency of 8.66 (±0.06)%, which was higher than the 8.12(±0.10)% efficiency of the conventional Pt-sputtered counter electrode. A decrease in ohmic internal resistance was also observed though EIS measurement. And the new counter electrode combined with the Pt hollow spheres electrode gave the energy conversion efficiency of 9.83(±0.14)%. [Copyright &y& Elsevier]

One potential strategy to develop hydrogen evolution electrocatalysts for producing sustainable hydrogen in water electrolysis is creating electrocatalysts with low-cost, high activity, and high stability. Herein, we show that low-loading metal-based tungsten oxide (WO 3) can be used as electrocatalysts for the hydrogen evolution reaction (HER) in acid, alkaline, and alkaline-seawater electrolytes. Among prepared electrocatalysts, rhodium (Rh)-WO 3 exhibits a high HER activity with the values of overpotential of 48, 116, and 98 mV to obtain a current density of 10 mA cm−2 in acid, alkaline, and alkaline-seawater electrolytes, respectively. In addition, the Rh-WO 3 electrocatalyst shows high stability during the HER operation for over 60,000 s. Besides, the application of Rh-WO 3 electrocatalyst as cathode and commercial ruthenium oxide (RuO 2) as an anode for overall water splitting show excellent efficiency with only a potential of 1.45 V to a current density of 10 mA cm−2 in the alkaline-seawater electrolyte. The Rh-WO 3 //RuO 2 cell also exhibits high stability for over 80,000 s and maintains a current of 15 mA cm2 at a cell voltage of 1.51 V. The results provide evidence that Rh-WO 3 can be a promising HER catalyst for sustainable hydrogen production via alkaline-seawater electrolysis application. [Display omitted] • Low loading of Rh was synthesized on WO 3 nanosheets. • 5 wt% Rh-WO 3 exhibits excellent HER activity in the alkaline-seawater electrolyte. • The hydrogen spillover effect can improve the HER activity for the catalysts. • 5 wt% Rh-WO 3 as cathode shows the excellent water splitting process in the alkaline-seawater electrolyte. [ABSTRACT FROM AUTHOR]

This study presents the first use of a plasma reduction reaction under atmospheric pressure to fabricate a thin silver layer on polyethylene terephthalate (PET) film without the use of toxic chemicals, high voltages, or an expensive vacuum apparatus. The developed film is applied to electromagnetic interference (EMI) shielding. After repeatedly depositing a silver layer through a plasma reduction reaction on PET, we can successfully fabricate a uniformly deposited thin silver layer. It was found that both the particle size and film thickness of thin silver layers fabricated at different AgNO 3 concentrations increase with an increase in the concentration of AgNO 3 . However, the roughness of the thin silver layer decreases when increasing the concentration of AgNO 3 from 100 to 500 mM, and the roughness increases with a further increase in the concentration of AgNO 3 . The EMI shielding effectiveness (SE) of the film is measured in the frequency range of 0.045 to 1 GHz. As a result of optimizing the electrical conductivity by measuring sheet resistance of the thin silver layer, the film fabricated from 500 mM AgNO 3 exhibits the highest EMI SE among all fabricated films. The maximum values of the EMI SE are 60.490 dB at 0.1 GHz and 54.721 dB at 1.0 GHz with minimum sheet resistance of 0.244 Ω/□. Given that the proposed strategy is simple and effective, it is promising for fabricating various low-cost metal films with high EMI SE. [ABSTRACT FROM AUTHOR]

The Pt layer deposited on a cylindrical micro cavity patterned Petri dish, which is produced using a one-step solvent-immersion phase separation, is fabricated for the first time as an FTO-free counter electrode (CE) for dye-sensitized solar cells (DSCs). Due to the high specific active surface area of the Pt-deposited honeycomb substrate CE, the efficiency of the DSC using the developed CE substrate is enhanced by 14.5% compared with the device using a Pt-sputtered flat substrate. This design strategy has potential in fabricating highly efficient and low-cost CE materials with FTO-free substrates for DSCs. [ABSTRACT FROM AUTHOR]

BACKGROUND: Reducing compensatory strategies during repetitive upper-limb training may be helpful in relearning motor skills. OBJECTIVE: To explore the effects of modified constraint-induced movement therapy (mCIMT), additionally modified by adding trunk restraint (TR), on upper-limb function and activities of daily living (ADLs) in early post-stroke patients. METHODS: Twenty-four participants with early stroke were randomly assigned to mCIMT combined with TR (mCIMT + TR) or mCIMT alone. Each group underwent twenty sessions (1 h/d, 5 d/wk for 4 weeks). Patients were assessed with the action research arm test (ARAT), the Fugl-Meyer Assessment-Upper extremity (FMA-UE), the Modified Barthel index (MBI), the Maximal elbow extension angle during reaching (MEEAR), and Motor Activity Logs (MAL-AOU and MAL-QOM). RESULTS: ThemCIMT + TRgroup exhibited greater improvement in theARAT, FMA-UE, MBI, MEEAR, andMAL-AOU, and MAL-QOM than the mCIMT group. Statistical analyses showed significant differences in ARAT (P = 0.003), FMA-UE (P = 0.042), MBI (P = 0.001), MEEAR (P = 0.002), and MAL-AOU (P = 0.005) between the groups. CONCLUSION: Modified CIMT combined with TR may be more effective than mCIMT alone in improving upper-limb function and ADLs in patients with early stroke. [ABSTRACT FROM AUTHOR]

Solar-to-steam (STS) generation based on plasmonic materials has attracted significant attention as a green method for producing fresh water. Herein, a simple in situ method is introduced to fabricate Au nanoparticles (AuNPs) on cellulose filter papers as dual-functional substrates for STS generation and surface-enhanced Raman spectroscopy (SERS) sensing. The substrates exhibit 90% of broadband solar absorption between 350 and 1800 nm and achieve an evaporation rate of 0.96 kg·m−2·h−1 under 1-sun illumination, room temperature of 20 °C, and relative humidity of 40%. The STS generation of the substrate is stable during 30 h continuous operation. Enriched SERS hotspots between AuNPs endow the substrates with the ability to detect chemical contamination in water with ppb limits of detection for rhodamine 6G dye and melamine. To demonstrate dual-functional properties, the contaminated water was analyzed with SERS and purified by STS. The purified water was then analyzed with SERS to confirm its purity. The developed substrate can be an improved and suitable candidate for fresh water production and qualification. [ABSTRACT FROM AUTHOR]

This study presents the synthesis of PtNi alloys with different volume ratios of Pt and Ni precursors in mixture solutions using dry plasma reduction under atmospheric pressure and low temperature. The developed materials are applied as efficient counter electrodes (CEs) in dye-sensitized solar cells (DSCs). The investigation of the Pt utility in PtNi alloys for electrocatalytic activity, and cost effective and highly efficient DSCs are also investigated. Compared with the reference electrodes (Pt and Ni CEs), the developed PtNi alloy CEs exhibit better reversibility as indicated by the peak-to-peak separation and better catalytic activity for the regeneration of iodide ions from triiodide ions. Thus, the DSC with the developed PtNi CEs provides higher efficiency than that of the device fabricated with the reference electrodes. [ABSTRACT FROM AUTHOR]

This work presents the synthesis of Co x Pd 1-x alloys (0 ≤ x ≤ 1) on a reduced graphene oxide (RGO) surface using the dry plasma reduction method. The formation of CoPd alloys on the RGO surface is confirmed through high-resolution scanning electron microscopy (HRSEM) and X-ray photoelectron spectroscopy (XPS) measurements, and transmittance electron microscopy (TEM). Then, the developed materials are applied as Pt-free counter electrodes (CEs) in dye-sensitized solar cells (DSCs). In order to obtain efficient CEs, the chemical composition of the Co x Pd 1-x /RGO is controlled through optimizing the volume ratio of the Co and Pd precursors during the synthesizing process. Due to the optimization of the charge-transfer resistance ( R ct ) and the diffusion impedance ( Z w ) values of the Co 0.9 Pd 0.1 /RGO CE, the device using the Co 0.9 Pd 0.1 /RGO CE exhibits the highest efficiency among the fabricated cells. Note that the cells using Co/RGO and Pd/RGO exhibit efficiencies of 5.17% and 5.41%, respectively. The proposed strategy is simple and efficient; thus, it is promising for fabricating highly efficient and low-cost CE materials for DSCs. [ABSTRACT FROM AUTHOR]

This study is the first to report highly efficient production of homogeneous large-scale thin polymer films with a sponge-like porous structure via an improved phase separation method. A mixture of tetrahydrofuran and methanol, which is used as a highly volatile solvent/nonsolvent pair, is crucial to induce phase separation and thus determines the resulting structure. The obtained porous structure is composed of intermingled sticks in a size range of 50–100 nanometers and bumps with a diameter of about 200 nanometers, revealing a morphology that resembles a bird's nest. The pore size and porosity of the porous film are finely controlled by varying the mixture composition. Furthermore, by employing a water-soluble interlayer before the phase separation process, the obtained porous film, even with extremely large area, can be easily detached from solid substrates without damaging the film. Notably, it possesses a skin-free layer at the bottom side where it contacts the interlayer surface. The formation mechanism of the sponge-like porous structure was studied and it was found that the progressive enrichment of methanol during the evaporation process is favorable for absorbing water vapor from the air into the solution, which is responsible for phase separation. In addition, a water-miscible mixture of solvent and nonsolvent, which can delay the liquid-liquid demixing process, is essential for the formation of the sponge-like porous structure. [ABSTRACT FROM AUTHOR]

[Display omitted] • The CuTi@Pt x alloy nanotubes are synthesized with porous core–shell structure via galvanic replacement. • In-depth analyses of CuTi@Pt x NTs including morphologies, structure, and composition are described. • CuTi@Pt x alloy NTs reveal efficient electrocatalysis towards hydrogen evolution reaction. • The optimized CuTi@Pt 0.24 NTs show 1.12 times lower in Tafel value and achieve enhanced durability of remaining unchanged over 24 h compared with Pt/C. High-quality electrocatalysts for hydrogen evolution reactions, which have long-term stability and high efficiency, are a major challenge. Enhancing electrocatalytic efficiency can be achieved by creating alloys, designing core–shell structures, and controlling shapes. Herein, we demonstrate an elevated performance CuTi@Pt alloy catalyst with a one-dimensional nanotube structure through a galvanic replacement reaction. While the Pt/Cu atomic ratio and the wall thickness of the nanotube are carefully tuned, the CuTi@Pt alloy phase and tube structure are consequentially controlled. A systematic investigation is then conducted into the differences in composition and shape that impact the activity and durability. The optimized CuTi@Pt nanotube catalyst shows significant enhancements in the HER activity (1.12-fold decrease in Tafel compared to the commercial Pt/C) and the durability (remains unchanged after 24 h). [ABSTRACT FROM AUTHOR]

A core-shell hierarchical nanoarchitecture consisting of Ni-layered double hydroxide nanosheets (Ni(OH) 2 NSs) grafted on Ag nanowires (Ag NWs) backbone is rationally designed and built by an in situ growth route, in which Ag NWs act as core and Ni(OH) 2 NSs as shell. The resulting hybrid material (Ag NW@Ni(OH) 2 NS), displayed a three-dimensional structure with a well-defined core-shell configuration and enlarged surface area, exhibits excellent electrocatalytic performance and enhanced durability. An electrochemical analysis exhibits that the Ag NW@Ni(OH) 2 NS-2H catalyst is a low overpotential of 290 mV required the achievement of a current density at 10 mA cm−2 (j 10) and excellent long-term stability sustained over 24 h with only 6% potential increment at j 10 versus initial potential. Unique micro/macrostructure and synergistic effects are responsible for the extraordinary electrochemical performance of Ag NW@Ni(OH) 2 NS-2H core-shell composite. Ag NWs behave like a high conductive backbone due to their low intrinsic resistance, thus promoting charge transfer, whereas the hierarchical Ni(OH) 2 nanosheets, with huge surface area, provide a large number of active sites for oxygen evolution reaction, leading to enhanced electrochemical activity. [Display omitted] • Hierarchical nickel double layer hydroxide nanosheet ((Ag NW@Ni(OH) 2 NS) architectures were grown on silver nanowires. • Ag NW@Ni(OH) 2 NS were explored as a novel and durable electrocatalyst for catalyzing OER in alkaline media. • Synergistic effects of ionic/electric channels are responsible for the extraordinary OER performance of Ag NW@Ni(OH) 2 NS. • The optimized Ag NW@Ni(OH) 2 NS-2H catalyst maintains 94% of the initial potential after 24 h. [ABSTRACT FROM AUTHOR]

This study develops a strategy to optimize the chemical state of bimetallic PtRu alloys in order to increase the catalytic activity of the PtRu alloy/RGO counter electrodes (CEs) used in efficient dye-sensitized solar cells (DSCs). The well-dispersed bimetallic Pt 1-x Ru x (0 ≤ x ≤ 1) nanoparticles (NPs) are stabilized with RGO after co-reduction of the metal precursor ions and graphene oxide. The nanohybrids exhibit a 3D network structure of RGO with a high NP loading on the RGO surface. The NP size is in range of 1–5 nm, with an average size of 2.5 nm. X-ray diffraction spectroscopy and HAADF-STEM measurements are conducted in order to confirm the structure of the PtRu alloy/RGO nanohybrid. As a result of optimizing the nanohybrid structure for high catalytic activity toward the reduction of the triiodide ions, the Pt 0.7 Ru 0.3 NPs/RGO nanohybrid exhibited the highest electrocatalytic activity, which corresponds to the lowest charge transfer resistance of 3.29 Ω, among the electrodes. The DSC fabricated with Pt 0.7 Ru 0.3 NPs/RGO CEs exhibits increases in efficiency of 12% compared with that of the Pt/RGO-based DSC and of 24% more than the efficiency of the Pt-free device. The obtained results indicate that tailoring the electronic structure of an alloy can be used to enhance the catalytic activity of nanohybrid CEs, and in turn for the construction of high-efficiency DSCs. [ABSTRACT FROM AUTHOR]

This study reports for increasing the efficiency of perovskite solar cells (PSCs) by modifying the surface of a fluorine-doped indium tin oxide (FTO) substrate using an atmospheric pressure plasma treatment. Surface modification of the FTO film involved several challenges, such as control of the blocking layer uniformity, removal of pinholes, and deposition of a dense layer. This strategy allows the suppression of charge recombination at the interface between the FTO substrate and hole conductor. Electrochemical impedance spectroscopy analysis showed that the plasma treatment increased the charge transfer resistance between the FTO and hole conductor from 95.1 to 351.1 Ω, indicating enhanced resistance to the electron back reaction. Analyses of the open-circuit photovoltage decay revealed that modification of the surface of the FTO substrate by plasma treatment increased time constant from 6.44 ms to 13.15 ms. The effect is ascribed to suppression of the electron recombination rate. PSCs based on the newly developed electrode had 39% higher efficiency than reference devices. The obtained results provide direct evidence in favor of the developed strategy. [ABSTRACT FROM AUTHOR]

Interfacial solar steam generation (ISSG) is one of the promising solutions in the field of water filtration, desalination, and solvent recovery. For the industrial applications of the technology, there is a need for developing highly durable, thermally stable, and inert light absorbers. Therefore, this work addresses this issue by synthesizing black Titania (B–TiO 2) via vacuum annealing and depositing it on glass fiber (GF) via vacuum filtration with an ethyl cellulose binder. According to the characterization techniques analyses, the change of colour is attributed to the occurrence of oxygen vacancies in the surface layers of TiO 2 nanoparticles during vacuum annealing. The deposition parameters were optimized for achieving a maximum solar-weighted light absorptance of 95.7%. The optimized B–TiO 2 GF was applied for the steam generation experiments and achieved the evaporation rate of 1.53 kg m−2 h−1, which corresponds to solar-steam conversion efficiency of 97.7 % under standard measurements condition of AM 1.5 G sun and ambient temperature and relative humidity of 20 °C and 40% respectively. Thanks to the high durability and chemical inertness of B–TiO 2 GF it was applied for water filtration in extreme conditions of acidic/alkaline water and high-sun illumination (up to 35-sun). Worth noting that for high-sun experimentation there is a need to use a binder to improve particle attachment to the glass fibers. • Eco-friendly synthesis of black titania is achieved. • Highly durable inorganic light absorber is realized for solar desalination. • Oxygen vacancies are enriched in black titania. • Ethyl cellulose acts as a binder for the light absorber. • Interfacial solar steam generation is applied using black titania. [ABSTRACT FROM AUTHOR]

We report the effect of the thermal reduction time during sintering on the electrocatalytic activity and the morphology of platinum nanoparticles (Pt-NPs) fabricated using thermal decomposition method. A uniform and dense distribution of Pt-NPs on fluorine-doped tin oxide glass substrate was achieved by controlling the thermal reduction time higher than 15 min and this morphology of Pt-NPs was responded for high electrocatalytic performance of counter electrode (CE). As expected, the excellent electrocatalytic activity with low charge-transfer resistance of 1.04 Ω cm2 and highly conductivity of Pt-NPs CE prepared at the thermal reduction time of 15 min during sintering was obtained, which was desirable for dye-sensitized solar cells. The energy conversion efficiency of 9.43 % was obtained for the thermal reduction time of 15 min with fill factor of 63.05 %, JSC of 18.82 mA cm-2 and VOC of 795 mV. [ABSTRACT FROM AUTHOR]

Abstract: This study demonstrated a simple micropatterning method using engineered surface and microcontact printing (μCP). For the selection of appropriate surface, several representative surfaces modified with various functional materials including aldehyde, epoxide, poly-l-lysine, amine, and self-assembled polyelectrolyte multilayers (PEL) were investigated. The PEL coated surface endowing electrostatic interaction force showed most high functionality in point of homogeneous patterning of proteins with high density and preservation of inherent three-dimensional structure of proteins. The printed sizes of protein micropatterns were almost identical to the used microstamp, which proves the μCP method is independent of diffusion of the transferring proteins. At last, the immunoassay as a model system of protein–protein interaction showed good linearity over a range from 100 to 25μg/ml, indicating the feasibility of a quantitative measurement of the concentration of target proteins in sample. Our proposed approach will be useful for the development of biomedical microdevices because of green chemistry, simple process, and high potential of various applications. [Copyright &y& Elsevier]

Abstract: In the field of the temperature sensitive drug delivery systems, we studied on the surface modification of liposomes by using poly(N-isopropylacrylamide-co-acrylamide) (PNIPAM-AAM) and polyethyleneglycol (PEG) to increase the release of doxorubicin (DOX) from liposomes and prolong the stability of liposomes in the presence of serum. The release of DOX from the PNIPAM-AAM/PEG modified liposomes is enhanced around the transition temperature of the polymer. In addition, the stability of the PNIPAM-AAM/PEG modified liposomes in serum shows a high level comparing with polymer unmodified liposomes. These results suggest that the modification on the surface of liposomes with both PNIPAM-AAM and PEG enhances the drug release from liposomes and reduces the protein adsorption in serum. [Copyright &y& Elsevier]

Metal nanoparticles encapsulated in graphitic carbon can show high catalytic efficiency and stability, yet the production method remains improved. Herein, it is demonstrated that a Ni‐based metal–organic framework [EG‐MOF‐74(Ni)] can be rapidly transformed into ultrasmall Ni‐nanoparticles with different sizes (4–11 nm) encapsulated in graphitic carbon via the laser‐scribing method. The synthesized sample shows the best electrocatalytic performances with excellent stability in alkaline electrolyte for oxygen/hydrogen evolution reactions with overpotentials of 0.35/0.18 V at a current density of 10 mA cm−2 when the Ni particle size is ≈6 nm. This is because of its well‐developed micro/mesoporous structure, high electronic transport, and large electrochemical active surface area. An electrolyzer with Ni‐nanoparticles encapsulated in the graphitic carbon shows a current density of 10 mA cm−2 at a voltage of 1.6 V, which is comparable to the Pt/C and RuO2 counterparts. The laser‐based synthesis can serve as a powerful tool for the size‐controlled synthesis of various catalysts out of MOFs. [ABSTRACT FROM AUTHOR]

Owing to its high conversion efficiency of solar energy and transformative industrial potential, solar-driven interfacial evaporation has been proposed as a promising alternative to conventional bulk heating-based evaporation, potentially reducing thermal losses and improving energy conversion efficiency. By using the process of plant transpiration, we developed here the Limnobium laevigatum inspired nanogenerator (LLN) made of multi-walled carbon nanotubes (MWNTs)-coated cellulose paper-located on Polystyrene (PS) foam that can float on water surface with high electricity generation and excellent freshwater production in water-rich locations such as lakes, rivers, and oceans at all hours of the day. LLN can achieve a high power density of over 50 mW m−2 and procedure freshwater at high evaporation rates of 1.48 kg m−2 h−1 during the daytime and 0.58 kg m−2 h−1 in the night, at an ambient temperature of 20 °C and humidity of 40%. The maximum power density of an LLN can be as high as 248.57/107.38 mW m−2 with a NaCl solution of 0.6 M under 1-sun/0-sun conditions that is expected the same value for seawater. The LLN can support useful power in offshore locations or deserted islands. Image 1 • A dual-function Limnobium laevigatum inspired nanogenerator (LLN) is developed. • A single LLN produces electric power of 248.57/107.38 mW m−2 under 1-sun/0-sun. • The highest water evaporation rate of LLN is 1.48 kg m−2 h−1. • LLN can work at all hours of the day. [ABSTRACT FROM AUTHOR]

Co x Sn 1-x /RGO nanohybrids synthesized using the plasma-assisted reduction are employed as counter electrodes in dye-sensitized solar cells. The optimization of the synthesis conditions has led to favorable morphology, which in turn resulted in higher catalytic activity. • Bimetallic CoSn alloy/RGO hybrids are synthesized using plasma reduction. • DSC employing the Co 0.9 Sn 0.1 /RGO counter electrode reveals the highest efficiency. • Electrocatalytic activity and electric conductivity are significantly enhanced. • CoSn alloy/RGO is an effective candidate for Pt-free counter electrodes in DSCs. The high cost of state-of-the-art Pt counter electrodes (CEs) hinders the large-scale applications of dye-sensitized solar cells (DSCs). The development of Pt-free catalysts while maintaining state-of-the-art catalytic activity for CE materials is one mean to reduce costs. Here, Co x Sn 1-x /reduced graphene oxide (RGO) (0 ≤ x ≤ 1) nanohybrids were synthesized and employed as inexpensive, stable, and earth-abundant CEs in DSCs. The synthesis was performed through the plasma-assisted reduction of the oxygen functional groups of the graphene oxide along with the immobilization of bimetallic nanoparticles (NPs) on the surface of RGO. The optimization of the composition of the alloy NPs for the highest efficiency of DSC yields the Co 0.9 Sn 0.1 /RGO nanocomposite. The highest device performance correlates well with the experimentally obtained lowest charge transfer resistance in conjunction with the highest electrocatalytic activity of the Co 0.9 Sn 0.1 /RGO CE. The DSC employed the synthesized CE showed good stability over long term operation. Both the developed CoSn/RGO nanohybrids and the strategy used for their synthesis are cost-effective. Our results provide economically implementable and green nanotechnology for efficient and stable DSCs required for commercialization. [ABSTRACT FROM AUTHOR]

• Bimetallic PtSe nanoparticles are prepared by means of dry plasma reduction. • The electrocatalytic activity as well as the electric conductivity are significantly enhanced. • The highest efficiency is recorded from a DSC with Pt 0.9 Se 0.1 CE. • The strategy presented here can be used to optimize the ratio of Pt x Se 1-x bimetallic nanoparticles in PV devices. This study reports on the synthesis of Pt x Se 1-x (0 ≤ x ≤ 1) nanoparticles (NPs) with different volume ratios of Pt and Se in mixed precursor solutions on a transparent conducting oxide electrode using dry plasma reduction (DPR). DPR can work under atmospheric pressure without the use of any toxic chemicals and at a low temperature. The developed Pt x Se 1-x (0 ≤ x ≤ 1) NPs immobilized on FTO glass substrates were first employed to the counter electrodes (CEs) for efficient dye-sensitized solar cells (DSCs). The morphology and trends of Pt x Se 1-x (0 ≤ x ≤ 1) NPs were observed by scanning electron microscope (HRSEM) and transmission electron microscope (TEM), while varying the ratio of platinum to selenium precursor. In addition, physical and chemical characteristics of Pt x Se 1-x (0 ≤ x ≤ 1) NPs were analyzed by photoelectron spectroscopy (XPS). Electrochemical properties for the catalytic activity of CEs were also measured and analyzed by Tafel, Electrochemical Impedance Spectroscopy (EIS) and Cyclic Voltammetry (CV). As a result, the CE prepared at the volume ratio of Pt 0.9 Se 0.1 exhibits the lowest charge transfer resistance of 0.85Ω. Therefore, the device fabricated with Pt 0.9 Se 0.1 alloy electrode shows the highest efficiency of 5.91% among all cells. This is also higher than the efficiency rates of 5.54% and 0.13% for cells fabricated with Pt NP and Se NP CEs, respectively. The obtained results indicate the potential use of PtSe alloy CEs in robust and efficient DSCs. [ABSTRACT FROM AUTHOR]

• Sponge-like NiAu nanoalloys are prepared using a simple method without any surfactant. • Electronic coupling between Ni and Au atoms can improve the HER activity. • The plasma-treated sponge-like NiAu nanoalloy exhibits enhanced HER performance. We report a method for synthesizing a plasma-treated sponge-like NiAu nanoalloy to enhance the hydrogen evolution reaction (HER) performance. First, an as-prepared sponge-like NiAu nanoalloy is obtained by using NaBH 4 to reduce a NiCl 2 and HAuCl 4 mixture without using any surfactant. Second, this as-prepared sponge-like NiAu nanoalloy is treated by argon plasma under atmospheric pressure with a treatment time of 15 min to obtain the final plasma-treated sponge-like NiAu nanoalloy. The HER electrocatalytic performance of the plasma-treated sponge-like NiAu nanoalloy is then investigated in 0.5 M H 2 SO 4 electrolyte. From the results, the plasma-treated sponge-like NiAu nanoalloy exhibits enhanced HER performance compared to the as-prepared sponge-like NiAu nanoalloy due to the exposure of more active/edge sites. The overpotential at a current density of 10 mA.cm−2 of the plasma-treated sponge-like NiAu nanoalloy (88 mV) is lower than that of the as-prepared sponge-like NiAu nanoalloy (134 mV), and this is due to the plasma treatment process. In addition, plasma-treated sponge-like NiAu nanoalloy shows an excellent durable ability of HER activity for 80,000 s. [ABSTRACT FROM AUTHOR]

• A facile liquid plasma is introduced to synthesize Ru/RGO nanocomposites. • Ru nanocrystals are homogeneously distributed on the RGO surface. • The Ru/RGO nanocomposites processed high capacitance of 136.7 F·g−1. • Dye-sensitized solar cells fabricated with Ru/RGO shows 6.78% efficiency. The synthesis of advanced functional nanomaterials for electrochemical applications, such as water splitting, dye-sensitized solar cells (DSCs), and supercapacitor has been the topic of interest in recent years. This work presents the synthesis of ruthenium (Ru)/reduced graphene oxide (RGO) nanocomposite by using a facile and scalable liquid plasma-assisted method and its application as an electrode material in electrochemical applications for supercapacitor and triiodide reduction at counter electrodes (CEs) of DSCs. As the results, Ru nanoparticles have a size in the range of 4–10 nm that were homogenously distributed on the surface of the RGO layer. Electrochemical measurements demonstrated that the synthesized material is suitable for supercapacitor applications, whereas the capacitance is approximately 136.7 F·g−1 at a scan rate of 20 mV·s−1. The developed materials are applied in CEs of DSCs. We found that the efficiency of 6.78% for DSCs with CE fabricated by Ru/RGO which is higher than that of 6.20% for a cell assembled with Pt electrode. [ABSTRACT FROM AUTHOR]

Nanosized plasmonic metallic nanoparticles such as Pd have gained significant attention due to their diverse applications in catalysis, sensing, and light-to-heat conversion. However, the development of scalable and environmentally friendly synthesis routes for such nanoparticles is crucial for the sustainable development of industrial applications. In this work, we address this challenge by synthesizing Pd-nanoparticles on the cellulose filter paper (Pd-Cellulose) via two scalable green synthesis routes: low-temperature thermal and plasma synthesis. We found that adjusting synthesis conditions allowed us to achieve an optimum morphology that maximizes light absorptance. The nature of the reduction species during synthesis significantly impacts the morphology and heat-transfer properties of the resulting material. Compared to thermally synthesized Pd-Cellulose, the absorbers synthesized with plasma have smaller particles size and higher coverage, which leads to higher broadband light absorptance and more intense heat transfer to the surroundings. The optimized Pd-based light absorbers were utilized in a solar-to-steam desalination system, resulting in an evaporation rate of 1.30 kg/m2h for the open system and a filtration rate of 0.7 kg/m2h for the closed system. Our findings provide insights into the green and scalable synthesis and optimization of Pd-based light absorbers and their potential application in sustainable renewable energy systems. [Display omitted] • Pd-nanoparticles are synthesized via two synthesis routes: thermal and plasma synthesis. • The optimum morphology is achieved for maximized light absorptance. • The nature of the reduction species impacts the morphology and heat-transfer properties of nanoparticles. • A new lab-scale solar-to-steam desalination system with Pd-Cellulose is developed. [ABSTRACT FROM AUTHOR]

The development of Ni-based nanoalloys has been extensively explored due to their low cost, high activity, and durability in the hydrogen evolution reaction (HER). Structural design of Ni-based nanoalloys is a promising approach to attain excellent electrocatalytic activity as well as stability of these catalysts. This study reports a facile method to prepare Ni x Rh y nanosponges while using NaBH 4 as a reducing agent without any surfactant. The ratio of Ni and Rh has been changed to obtain various Ni x Rh y electrocatalysts (Ni, Ni 3 Rh 1 , Ni 1 Rh 1 , Ni 1 Rh 3 , and Rh), respectively. Among the prepared catalysts, Ni 1 Rh 3 electrocatalyst exhibits a high electrocatalytic activity with an overpotential of 48 mV at a current density of −10 mA cm−2 and a superior stability even after 2000 cycles of CV in 0.5 M H 2 SO 4 electrolyte. In addition, the Ni 1 Rh 3 electrocatalyst shows good electrocatalytic activity in 1.0 M KOH electrolyte compared to commercial Pt/C (20 wt% of Pt) (c-Pt/C). Moreover, the overall water splitting system of the Ni 1 Rh 3 cathode and the commercial RuO 2 anode is evaluated, not only exhibiting excellent performance with a potential of 1.52 V at a current density of 10 mA cm−2, but also proving very stable operation for over 100,000 s in 1.0 M KOH electrolyte. Image 1 • NiRh alloy nanosponges are prepared using a facile method without any surfactant. • Rh-rich NiRh alloy nanosponges retain high crystallinity. • Electronic coupling between Ni and Rh atoms can enhance the HER activity. • NiRh nanosponges exhibit excellent HER performance. [ABSTRACT FROM AUTHOR]

A new type of three-dimensional PtMo nanosponge wrapped with graphene dots (abbreviated as 3D Pt x Mo 1-x @graphene) has been developed for catalyzing the hydrogen evolution reaction (HER). The graphene-dot wrapping takes place via the exfoliation of carbon dots during the co-reduction of Pt/Mo precursors and carbon dots at a low temperature in an aqueous solution. The synergistic effects of inner metallic alloy networks and outer graphene dots in the 3D Pt x Mo 1-x @graphene are responsible for the outstanding HER performance and superb durability in both acidic and alkaline electrolytes. The 3D Pt x Mo 1-x @graphene shows a low Tafel slope of 32 mV/dec and 51 mV/dec together with a low overpotential of 32 mV and 97 mV at a current density of −10 mA cm−2 in acidic and alkaline media, respectively. The catalyst also shows superb stability, as confirmed by a large amount of repeated potential cycling exceeding 5000 cycles in acidic solution and long-term durability of over 50,000 seconds in an alkaline solution. This work provides a new feasible mean of synthesizing graphene-dot-wrapped Pt-based nanostructures with highly efficient catalytic activity and superb stability for HER without the need for surfactants or stabilizers. Image 1 [ABSTRACT FROM AUTHOR]

Abstract Dry plasma reduction under atmospheric pressure is a unique approach for stably, continuously, easily, and uniformly fabricating Ag layer on the metal seeds-polyethylene terephthalate (PET) substrate. In this study, effects of particle size, surface uniformity, surface coverage, and film thickness of metal seeds such as Ag, Cu, Fe and Ni on the formation of uniform Ag layer were studied on the basis of their surface free energies and critical radius, which further leads to variations in the sheet resistance levels of the silver layers. The root mean square roughness and sheet resistance of the Ag layer PET substrate were decreased with the deposition of metal seeds. Among the added seed metals, Ni seed has shown best uniformity. Furthermore, the fabricated films were applied for electromagnetic interference (EMI) shielding. Among the added seed metals, Ni has shown the highest electromagnetic interference shielding effectiveness. The present study will be useful for the development of various low-cost metal films in the field of EMI shielding. Highlights • Uniform silver layer successfully fabricated with the aid of dry plasma reduction. • Fabricated films were applied as electromagnetic interference shielding materials. • Surface of silver layer formed more smoothly and uniformly by applying metal seeds. • The findings may be useful for the development of various low-cost metal films. [ABSTRACT FROM AUTHOR]

Abstract Development of highly efficient electrocatalysts to produce hydrogen has been a significant topic over the past few decades. Currently, the platinum metal group shows the best catalytic performance for the hydrogen evolution reaction (HER), but the high cost and low abundance of these materials limit their wider application. Therefore, we synthesized transition-metal-based NiCoS along with carbon dots (C-dots) as a structure-directing agent by a hydrothermal method. We also synthesized sulfur-doped NiCo, where the sulfur enhances the conductivity of the catalysts. Herein, the synthesis temperatures were changed in the range from 120 to 240 °C. Among all, NiCoS synthesized at 150 °C shows the best HER performance capabilities. In more detail, NiCoS prepared at this temperature exhibits an onset potential of 96 mV and an overpotential of 232 mV. Especially, as-prepared NiCoS nanoflower subjects to long-term stability over 20 h at a current density of 10 mA/cm2, making it a promising low-cost candidate for hydrogen production. Graphical abstract Image 1 Highlights • A carbon-dot (C-dot) assisted 3D nanoflower-like NiCoS electro-catalyst is synthesized. • The homogeneous growth of nano-sheets with void structure provides a large surface area. • Sulphur-doped NiCo synthesized at 150 °C exhibits the highest electro-catalytic activity. • The C-dot acts as a protective layer for NiCo and creates easy routes for electron transfers. [ABSTRACT FROM AUTHOR]

Abstract In the study, we used two conducting polymers, polyaniline (PANI) and polypyrrole (PPy), to sensitize Ta 3 N 5 , thereby enhancing its photocatalytic activity, and then applied this novel photocatalyst to overall water splitting to produce hydrogen and oxygen even under visible light irradiation. The two polymers increased the charge transfer efficiency, prevented the recombination of the generated electrons and holes of the Ta 3 N 5 photocatalyst, and thereby enhanced its electron-hole separation efficiency and improved its photocatalytic activity for efficient visible light water splitting. The two polymers completely covering the Ta 3 N 5 particles facilitated charge transfer for quick migration of the generated electrons and holes to the polymer surface and thus prevented contact between the holes and nitride of Ta 3 N 5. Therefore, these conducting polymers also protected the Ta 3 N 5 particles from self-photocorrosion during long-term water splitting. Because of the existence of the protonated nitrogen (-N+) state in PPy, the electric conductivity of PPy was lower than that of PANI, which lowered the sensitizing ability of PPy compared to that of PANI. Thus, the water splitting efficiency of Ta 3 N 5 /PANI was higher than that of Ta 3 N 5 /PPy. The production rates of H 2 and O 2 generated from water splitting of Ta 3 N 5 /PANI were 60.5 and 30.2 (μmol. g−1cat. h−1), respectively. Graphical abstract Image 1 Highlights • Polymer sensitizers enhanced the separation of e−/h+ pairs and prolonged the Ta 3 N 5 lifetime. • Polymer cover protected Ta 3 N 5 from self-photocorrosion (oxidation of generated holes). • Ta 3 N 5 /polymers greatly exhibited overall photocatalytic water splitting. • Lower electric conductivity lowered the sensitizing ability of the polymer. • PANI was better than PPy for enhancing the photocatalytic activity of Ta 3 N 5. [ABSTRACT FROM AUTHOR]

The aim of this study is to find optimal Ar plasma etching conditions without significantly altering the surface of PtFe bimetallic nanoparticles (BNPs). Various treatment parameters such as acceleration voltage, ion beam current, and etching time are considered in this study. Studies have shown that severe alteration of surface chemical composition is closely related to the energy of Ar ions. High energy (3 keV) Ar cleaning, leads to partial reduction of alloy particles along with decontamination. However, the use of ion energies of 1 keV or lower leads to preferential cleaning with minor alteration of surface chemistry and subsequently allows us to acquire reliable XPS data of PtFe BNPs. Profiling of the NPs revealed that both metal oxides and elemental metals are simultaneously synthesized during dry plasma reduction. PtO is formed at the level of 30 atomic percent in the synthesis procedure, which is due to the influence of oxygen radicals in atmospheric plasma. [ABSTRACT FROM AUTHOR]

Abstract The improvement of the catalytic performance for methanol and formic acid oxidation reactions remains a key issue for the development of a new generation of direct methanol and formic acid fuel cells. This study reports a simple approach, using selective chemical etching for the synthesis of unique nitrogen-doped carbon dot/Pt 84 Pd 16 (N-Cdot/Pt 84 Pd 16) nano-network structure at room temperature with excellent electrocatalytic properties. The obtained nano-network hybrid material exhibits significant enhancement of the electrocatalytic activity for the electro-oxidation reaction of both methanol and formic acid with current densities of 999.0 and 1919.5 mA/mg metal , respectively, compared with the commercial ones of 751.32 and 806.02 mA/mg metal , respectively. Furthermore, the N-Cdot/Pt 84 Pd 16 nano-network hybrid materials exhibit excellent stability and hydrophilic dispersibility at room temperature. Graphical abstract Image 1 Highlights • N-Cdot/PtPd nanonetwork hybrid material is synthesized at room temperature. • A simple coreduction and a selective chemical etching are applied to the synthesis. • It generates a nano-network structure with excellent electrocatalytic properties. • N-Cdot functions as a uniform interconnection between the nanohybrid materials. • The hybrid exhibits significant enhancement of the activity for both MOR and FAOR. [ABSTRACT FROM AUTHOR]

This study presents the synthesis of Fe x Sn 1-x alloys (0 ≤ x ≤ 1)/reduced graphene oxide (RGO) using a dry plasma reduction method. The formation of bimetallic FeSn nanoparticles on the surface of RGO was confirmed through TEM and XRD measurements. In the results, FeSn ranging from 1 to 5 nm in size is shown to be successfully immobilized on the RGO surface. The developed materials are then applied as Pt-free counter electrodes (CEs) in liquid-junction photovoltaic devices. To get efficient CEs, we have carefully controlled the chemical composition of the Fe x Sn 1-x /RGO through changing the volume ratio of the Fe and Sn precursors during synthesis. The catalytic activity of the electrodes follows the sequence of Fe 0.1 Sn 0.9 /RGO > Fe 0 Sn 1 /RGO > Fe 0.3 Sn 0.7 /RGO > Fe 0.5 Sn 0.5 /RGO > Fe 0.7 Sn 0.3 /RGO > Fe 0.9 Sn 0.1 /RGO > Fe 1 Sn 0 /RGO, with the Z w values of the developed electrodes lower than those of Sn/RGO and Fe/RGO electrodes. Accordingly, the highest efficiency was 5.0% for the device using Fe 0.1 Sn 0.9 /RGO CE, which is also higher than those of devices using Sn/RGO (4.6%) and Fe/RGO (3.8%). The proposed strategy is simple and efficient and is, therefore, promising for the fabrication of cost-effective CE materials for next-generation solar cells and lithium-ion batteries. [ABSTRACT FROM AUTHOR]

This study presents a strategy of fabricating a perovskite layer through chemical vapor deposition (CVD) method and applying it as an efficient absorber in PSCs based on SWCNT counter electrode. As the results, the CVD method produced smooth and void-free perovskite films, which reduced the moisture absorption at the grain boundaries then delayed the degradation of the organic/inorganic composition. Furthermore, the smooth surface of the dye layer enhances charge collection at the interface with counter electrodes. Thus, the efficiency of cell fabricated by CVD method was 7.9%, which is improved by 29.5% as compared with cells using the conventional spin-coating method. Furthermore, the cell fabricated by CVD method gave an excellent stability. Accordingly, the efficiency was lost only 17% after 500 h performances. This approach could pave the way to develop low-cost PSCs with long-term stability. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) culture dish patterned with a microwell structure demonstrates a great application potential in biotechnology. This study reports on the easy fabrication of an ordered customizable honeycomb microwell array on the surface of polymer substrates including the commercial Petri dish to create a biological platform for cell culture. The fabrication method is based on a very simple solvent dip-coating technique and the methanol accumulation-induced phase separation in which a binary mixture of chloroform and methanol is used to induce a ternary solution and to guarantee the formation of the ordered pore array on the substrate. The surface topology of the honeycomb substrate is manipulated through varying the experimental conditions; notably, the obtained honeycomb structure is part of the substrate, which reveals an increase in the structure’s stability for the practical applications. Honeycomb-structured Petri dish fabricated using this method is applied as a scaffold for cell growth to demonstrate its potential in biomedical applications. [ABSTRACT FROM AUTHOR]

In contrast with the conventional in situ and ex situ methods for the preparation of polymer-based nanocomposites in which the polymer matrix (for both methods) and metal nanoparticles (for the ex situ method only) are prepared separately prior to being combined to form the composite, polyhedral gold nanocrystal/polymer composite film was successfully synthesized through combining the in situ formation of gold nanocrystals (AuNCs) and simultaneous polymerization of the polyelectrolytes from ionic liquids and surfactants under atmospheric pressure plasma. The composite film contained a large number of well-shaped polyhedral AuNCs. The AuNCs are stereoscopically distributed in the polyelectrolyte matrix without agglomeration. The size of the AuNCs prepared in a 3 mm deep reactor decreased along the cross section of the composite film from top to bottom, while they were uniform in size when they were prepared in a 5 mm deep reactor. In the presence of the Au precursors, the polymer film thickness increases to 7.03 μm, which is two-fold thicker than that of the polymer film prepared without adding Au precursors. Through the density functional theory (DFT) calculations, the critical role of Triton X100 was clearly demonstrated in the formation of the well-shaped AuNCs. The composite film exhibited the reduction of ∼66% in Young's modulus and the reduction of ∼44% in hardness compared to the neat polymer film. Finally, an appropriate mechanism is proposed for the formation of the polyhedral AuNC/polyelectrolyte composite film. [ABSTRACT FROM AUTHOR]

This work presents the synthesis and immobilizing of bimetallic PtMo nanoparticles (NPs) on a Fluorine-doped tin oxide (FTO) substrate using a dry plasma reduction under atmospheric pressure at a low temperature and without using toxic reagents. These alloys are placed as counter electrodes (CEs) for efficient dye-sensitized solar cells (DSCs). For this purpose, an experimental approach is designed for the co-reduction of Pt and Mo precursors with different volume ratios. The TEM, HRSEM, XRD and XPS measurements are also obtained in order to analyze the morphology and chemical composition of the PtMo alloys, respectively. Furthermore, the electrochemical catalytic activities are examined through CV, EIS and Tafel measurements. The effect of the CEs on the efficiency of the devices is further confirmed using photovoltaic measurements. It is confirmed that the bimetallic PtMo NPs, with a small particle size, are successfully immobilized and well distributed on the FTO surface without agglomeration. The electrochemical catalytic activity of the electrodes follows the sequence of Pt 0.52 Mo 0.48 > Pt 0.83 Mo 0.17 > Pt 1 Mo 0 > Pt 0.43 Mo 0.57 > Pt 0.19 Mo 0.81 > Pt 0.08 Mo 0.92 > Pt 0 Mo 1 . The improvement in the catalytic activity of the developed materials results from the electronic effect that originates from the upward shift of the platinum d -band to the Fermi energy level upon alloying. Thus, the highest efficiency of 8.51% is archived for the cell using the Pt 0.52 Mo 0.48 CE. Note that the efficiency of the device using a Pt CE is only 7.86%. The results also indicate the improved stability of the developed CEs in iodide electrolyte. [ABSTRACT FROM AUTHOR]

Co x Ni 1-x alloys (0 ≤ x ≤ 1) are successfully synthesized and immobilized on a reduced graphene oxide (RGO) surface using the dry plasma reduction method. HRSEM and XPS measurements are used to analyze the morphology and chemical composition of the developed materials. Then, the developed materials are applied as Pt-free counter electrodes (CEs) in liquid junction photovoltaic devices. In order to obtain efficient CEs, the chemical composition of the Co x Ni 1-x /RGO is controlled through optimizing the volume ratio of the Co and Ni precursors during the synthesizing process. It is found that the highest efficiency was 6.75% for the device using Co 0.3 Ni 0.7 /RGO CE, which is also higher than those of the devices using Pt CE (6.63%), Co/RGO (6.33%), and Ni/RGO (5.52%). The obtained results can be explained through the optimization of the charge-transfer resistance and diffusion impedance values of the developed materials. The strategy is simple and efficient; thus, it is promising for fabricating cost-effective CE materials for dye-sensitized solar cells. [ABSTRACT FROM AUTHOR]

[Display omitted] • The micro-groove surface is created by the Fused Deposition Modeling technique. • The super-amphiphilic surface is obtained by optimizing the Ar plasma treatment. • The micro-groove surface outstanding transports both polar and non-polar solvents. • The micro-groove surface demonstrates a facile route to the fog harvesting surface. The development of the super-lyophilic surface has gained tremendous attention due to its wide applications in the industrial and engineering fields. However, there are still challenges in preparing super-amphiphilic surfaces, especially microstructure surfaces. This study reports the progress of fabricating the super-amphiphilic microgroove surface (SAMS) for multi-purposes via physical and chemical modification. First, the microgroove structure is achieved via the fused deposition modeling 3D printing method with layer-by-layer (XZ direction) printing; then, the surface chemical composition is adjusted via a low-pressure argon plasma treatment. Besides, the surface roughness factor and the hydroxyl group content are controlled via the printed layer height/nozzle diameter ratio and plasma treatment time to optimize the capillary force between grooves to obtain the most appropriate SAMS. The achieved SAMS shows the versatile ability to wick common solvents of various polarities, including carbon tetrachloride, ethylene glycol, ethanol, 1-decanol, hexane, and water. The wicking dynamic of liquids on SAMS fits well with Washburn's model at the initial stage, but it gradually moves out of the model. The simple and cost-efficient manufacturing process of SAMS can be scaled up for industrial applications like microfluidic and solvent recovery. [ABSTRACT FROM AUTHOR]