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The critical bottleneck for water splitting, which is important for sustainable production of hydrogen, has remained in sluggish oxygen evolving reaction (OER) requiring insufficiently low overpote...

Electrocatalytic splitting of water to oxygen and hydrogen is one of the most promising approaches for sustainable production of hydrogen as a carbon-neutral fuel. To establish efficient electrocatalytic water splitting, the overall overpotential for this reaction must be minimized via developing efficient catalysts to promote oxygen and hydrogen evolution at the anode and the cathode, respectively. However, the overpotentials for oxygen evolution are insufficiently low (162–300 mV for a current density of 10 mA cm−2), and the value less than 100 mV still remains untracked. Here, we report the unprecedentedly low of 32 mV for oxygen evolution attained by the formation of a unique motif of nickel sulfide nanowires stuffed into carbon nitride scabbards (NiSx/C3N4), demonstrating electrocatalytic water splitting at the lowest overall overpotential of 72 mV using the NiSx/C3N4 anode. This motif provides a key to guided thought for the development of efficient catalysts for oxygen evolution.

In this study, we have prepared thermally and chemically stable lamellar polymer films via humid annealing. The amphiphilic polymer poly(

The size-tunable synthesis of metal nanoparticles (MNPs) is important for revealing their size-dependent unique properties and practical applications. Here, we developed a size-tunable synthesis me...

Thin polymer films with perpendicularly aligned nanocylinder arrays were fabricated from block copolymers of poly(N-dodecylacrylamide) and poly(ethylene glycol) (pDDA-b-PEG). Reversible addition–fr...

Oxygen-evolution-reaction (OER) and oxygen-reduction-reaction (ORR) catalysts on a gas-diffusion carbon paper (CP) electrode have been explored as a current hot topic. Low-cost and earth-abundant F...

The development of efficient technologies to adsorb volatile organic compounds (VOCs) is desirable given their adverse effects on human health and the environment. Herein, we report a crystalline m...

An exclusive deposition method of Ag nanoparticles (NPs) on TiO2 particles has been developed. Ag NPs supported on TiO2 particles, Agx/TiO2, with various Ag weight ratios versus total weights of Ag and TiO2 between x = 2 and 16 wt% are prepared via low-temperature thermal decomposition of Ag(I)–alkyldiamine complexes generated by a reaction between AgNO3 and N,N-dimethyl-1,3-propanediamine (dmpda) in an aqueous medium suspending TiO2 particles. The thermal decomposition of the Ag(I)–alkyldiamine complexes is accelerated by TiO2 particles in the dark, indicating that the reaction catalytically occurs on the TiO2 surfaces. Under optimised reaction conditions, the thermal decomposition of the complex precursors is completed within 3 hours at 70 °C, and Ag NPs are almost exclusively deposited on TiO2 particles with high conversion efficiencies (≥95%) of the precursor complexes. The thermal decomposition rates of the precursor complexes are strongly influenced by the chemical structure of a family of water-soluble dmpda analogues, and dmpda with both primary and tertiary amino groups is adopted as a suitable candidate for the exclusive deposition method. The number-averaged particle sizes of the Ag NPs are 6.4, 8.4, 11.8 and 15.2 nm in the cases of Agx/TiO2, x = 2, 4, 8 and 16, respectively. To the best of our knowledge, the as-prepared Agx/TiO2 samples show one of the highest catalytic abilities for the hydrogenation reduction of 4-nitrophenol into 4-aminophenol as a model reaction catalysed by Ag NPs.

A new type of artificial giant liposome incorporating ion transport channels and using nanoparticles of metal organic frameworks was demonstrated. The micropores of Prussian blue nanoparticles served as ion transport channels between the outer and inner phases of liposomes.

Surface-sensitive information on a bulk sample can be obtained by using a low incident electron energy (low accelerating voltage/landing voltage) in a scanning electron microscope (SEM). However, topography and composition contrast obtained at low incident electron energies may not be intuitive and should be analyzed carefully. By combining an Auger electron spectrometer (AES) with a low incident electron energy SEM (LE-SEM), we investigated the SEM contrast carefully by separating the secondary electron (SE) and back-scattered electron (BSE) components with high accuracy. For this, we modified an AES to measure the electron energy in the range of 0–0.6 keV with a sample bias voltage of 0 to −0.3 keV. We could clearly observe reversed brightness of gold and carbon (graphite) in BSE images when the energy of the incident electrons was reduced to 0.2–0.3 keV. In addition, reflected electron energy spectroscopy (REELS) is known to be a tool for chemical state analysis of the sample. We demonstrated that it is possible to study the electron states of graphite, diamond, and graphene by acquiring low incident energy REELS spectra from their surfaces with the newly modified AES. This will be a new method for analyzing the electron states of local areas of a surface.

The semi-sitting position is well known to neurosurgeons. However, there are few reports of microvascular decompression surgery for glossopharyngeal neuralgia performed using the semi-sitting position. The semi-sitting position is not widely adopted in Japan, but it is considered to be a very useful neurosurgical position. Microvascular decompression surgery for glossopharyngeal neuralgia is a relatively rare procedure, and the semi-sitting position is very effective, considering the possibility of intraoperative cardiac arrest and postoperative complications of lower cranial nerve palsy. This report describes two cases of glossopharyngeal neuralgia operated in the semi-sitting position. Microvascular decompression was performed on both patients, and postoperative pain controls were good and no complications were observed. We show that the use of the semi-sitting position to perform microvascular decompression for glossopharyngeal neuralgia provides an excellent surgical view of the brainstem.

Nanorod architecture of a N2-intercalated WO3 photoanode has been developed by emphasizing the dual role of N2H4, which functioned simultaneously as a structure-directing agent and as a nitrogen so...

In the proofs of Theorems 3.5, 3.6 in [3], which give equality of the Fitting ideal of the class group of a CM-field and the Stickelberger ideal, we used Lemma 6.3 in [2], which bounds the index of the Fitting ideal in terms of the class number.

Cobalt hexacyanoferrate of various compositions was prepared in flow mode and the role of the vacancy on the structure, thermogravimetric (TG) properties, and the adsorption efficiency was studied. The material, Nay Co[Fe(CN)6 ]1-x ⋅z H2 O, with a minimum vacancy of x=0.014 to the highest x=0.47, was obtained. The TG-differential scanning calorimetry (DSC) profile showed a distinct influence of the vacancy on the water release temperature. Materials with x>0.35 showed a smooth release of water at a relatively lower temperature. However, for the materials with x

The phenomena involved in direct-current-driven electroluminescence (DC EL) was investigated, which occurred in the sintered pellets of ZnO doped with rare-earth (RE) and lithium. The microstructural observation revealed that the morphology of loosely-packed small-grains was advantageous for the DC EL, where the doped RE3+ was homogeneously dispersed over the ZnO matrix as small RE2O3 grains. The EL color was dependent on the type of the doped RE3+ and green, blue, or red EL was observed with Er3+, Tm3+, or Eu3+. The EL emission was recognized on the anode side. That brought a new multilayered structure concentrating RE3+ on the anode side to enhance the EL intensity. The occurrence of the EL on the anode side in the presence of an acceptor-type dopant lithium suggested the involvement of holes in the DC EL emission.

Prussian blue (PB) is a well-known porous metal–organic framework (MOF) material, whose redox chemistry on indium-tin oxide (ITO) electrodes has been studied extensively. However, the molecular interfacing of PB nanocrystals has not yet been explored in such detail. In this study, electrochemical interfacing of PB nanocrystals with a thin film containing a redox-active Ru complex (Ru-NP) was investigated. Spontaneous growth of preferentially oriented PB nanocrystals was observed on an ITO electrode modified with a Ru-NP primer film, which was subsequently characterized by UV-Vis-NIR spectroscopy, scanning electron microscopy (SEM), and X-ray diffraction (XRD) analysis. Blocking and rectification of electron transport (ET) were observed between PB and the Ru complex, and this behavior was governed by the energy gap between the Ru complex and PB nanocrystals as well as the thickness of the Ru-containing primer layer film. ET rectification at the ITO‖(Ru-NP)3/PB heterojunction was supported by a potential-step chronoamperometry (PSCA) analysis of the i–t curves. Owing to the large difference between the forward and backward ET rates at the ITO‖(Ru-NP)3/PB heterojunction, a large hysteresis loop was observed during electrochemical quartz crystal microbalance (EQCM) measurements, indicating dynamic ion transfer gating in the PB nanopores through the rectified electron transport between the Ru-NP layer and the ITO electrode at the ITO‖(Ru-NP)3/PB heterojunction.

Prussian blue (PB), an archetypal classic porous coordination polymer, has been rediscovered as a potential electrode material for ion secondary batteries due to its accommodations for alkali-metal ions. Many researchers have investigated the charge/discharge capacities of PB and its analogue (PBA) cells with binders. Binders, however, often obscure the underlying redox-coupled ion transport mechanism and the intrinsic transport pathways in PB and PBAs. Using binder-free PB film electrodes prepared by our low-temperature annealing method, we monitored the redox process accompanied by ion transport through simultaneous electrochemical and electrochromic measurements. We clarify that large pores of the defect lattice PB facilitate the efficient transport of bare and solvated Li+/K+, whereas small pores of the perfect lattice PB only allow bare Li+ to be transported up to inner lattice layers. This highlights the importance of pore/ion size selectivity and the (de)solvation effect. Quantum chemical calculations of a perfect lattice model revealed the size-dependent transport pathways of bare Li+ and K+, which microscopically corroborate the experimentally observed selectivity. In addition, spin density difference maps demonstrate that the Li+ transport can be facilitated not only by the electrochemical reduction of all FeIII centres but also by Li+-induced local redox reactions of the lattice framework. Our combined experimental and theoretical studies provide a fundamental understanding of the concealed structure–property relationship in PB films, thereby contributing to a more systematic design of high-performance PB/PBA electrodes.

Metal oxides with sizes of a few nanometers show variable crystal and electronic structures depending on their dimensions, and the synthesis of metal oxide particles with a desired size is a key technology in materials science. Although discrete metal oxide particles with an average diameter ( d) smaller than 2 nm are expected to show size-specific properties, such ultrasmall metal oxide particles are significantly limited in number. In nature, on the other hand, nanosized ferrihydrite (Fh), which is ferric oxyhydroxide, occurs as a result of biomineralization in ferritin, an iron storage protein cage. Here we describe the synthesis of Fh particles using a covalent molecular organic cage (MOC) derived from 8 + 12 cyclocondensation of triaminocyclohexane with a diformylphenol derivative. At the initial reaction stage, eight iron ions accumulated at the metal binding sites in the cage cavity, and Fh particles ( d = 1.9 ± 0.3 nm) encapsulated within the cage (Fh@MOC) formed with a quite narrow size distribution. The formation process of the Fh particle in the organic cage resembles the biomineralization process in the natural iron storage protein, and the present method could be applicable to the synthesis of other metal oxide particles. Fh@MOC is soluble in common organic solvents and shows substantial redox activity in MeCN.

For a finite abelian $p$-extension $K/k$ of totally real fields and the cyclotomic $\mathbb{Z}_{p}$-extension $K_{\infty}/K$, we prove a strong version of an equivariant Iwasawa main conjecture by determining completely the Fitting ideal over $\mathbb{Z}_{p}[[\mathop{\rm Gal}\nolimits(K_{\infty}/k)]]$ of the classical Iwasawa module $X_{K_{\infty},S}$, which is the Galois group of the maximal pro-$p$ abelian $S$-ramified extension of $K_{\infty}$, where $S$ contains all ramified primes in $K_{\infty}/k$. To do this, we prove a conjecture which was proposed in a previous paper by the first and second author, concerning the minors of a relation matrix for the second syzygy module of the trivial module $\mathbb{Z}$ over a suitable group ring.

Colloidal magnetite (Fe3O4) nanoparticles were synthesized via thermal decomposition of oleylamine-coordinated iron oxalate powder, which gradually becomes liquid at high temperature without the ne...

An exclusive deposition method of Ag nanoparticles (NPs) on TiO

Prussian blue (PB) is limited in its application by its breakdown at elevated temperatures. To improve the heat resistance of PB, we prepared a composite film comprising PB nanoparticles (NPs), smectite clay, and an organic compound. The composite film had a microstructure in which PB NPs were intercalated between smectite/organic compound layers. The predominant oxidation temperature of the PB NPs in the composite film was around 500 °C in air, higher than the oxidation temperature of bulk PB in air (250 °C). This improvement in the oxidation temperature may be due to the composite film acting as a barrier to oxygen gas. These results indicate the effectiveness of clay materials for the improvement of heat resistance for low-temperature decomposition compounds, not only PB but also other porous coordination polymers.

Adsorption of alkyl chain alcohols, ranging from methanol to n-hexanol, on manganese hexacyanocobaltate (MnHCCo) and copper hexacyanocobaltate (CuHCCo) nanoparticles was evaluated. The equilibrium adsorption capacity at low pressure was found to be larger than previously published results using other kinds of adsorbents, metal organic frameworks, zeolites, and activated carbons. For example, MnHCCo adsorbed 5 mmol/g of methanol at only 8.9 Pa, less than 1/10 of the lowest pressures used in previous studies. The adsorption can be understood using a two-step process: initial adsorption into the crystal (intra-nanoparticle adsorption) followed by that among the nanoparticles (inter-nanoparticle adsorption). The suggested mechanism was supported by the analysis of the adsorption isotherm with the dual-site Langmuir equation, and the entropy loss in the adsorption process. The highest adsorption amount at low pressure was caused by a combination of coordination bonding between alcohol molecules at the high-den...

An axial-substituted silicon phthalocyanine derivative, SiPc(OR)2 (R = C4H9), that is soluble in organic solvent is conveniently synthesized. This silicon phthalocyanine derivative reacts with a hydroxyl group on a substrate and then with another phthalocyanine derivative under mild conditions. The accumulation number of the phthalocyanine molecules on the substrates is easily controlled by the immersion time. On the basis of AFM (atomic force microscopy) images, the surface of the phthalocyanine-modified glass substrate has uneven structures on the nanometer scale. ITO electrodes modified with the composition of the phthalocyanine derivative and PCBM show stable cathodic photocurrent generation upon light irradiation.

Metal hexacyanoferrates (MHCFs), also called Prussian blue analogs, are known as electrochemical electrodes and are ion-adsorbent. To investigate the effect of the ionic radius of the adsorbate (cations adsorbed upon reduction) and the pore size of the adsorbent (porous electrode that stores cations upon reduction), we investigated the electrochemical reactions with various alkali cations and by changing the metal sites of the MHCFs. First, we succeeded in controlling the pore sizes of the MHCFs, where the lattice constant a could be estimated as a = 0.98Dsum + 7.21, where Dsum represented the sum of the ionic diameters of the metal M and Fe. Concerning the electrochemical reaction, the redox potential increased when the hydration energy of the adsorbate decreased, implying that the hydration energy of the adsorbate affected the stability of the reduced state. With cadmium hexacyanoferrate, which has a large pore size, the variation of the redox potential was suppressed in comparison to that with copper hexacyanoferrate, which has a small pore size. With Fourier transform-infrared (FT-IR) analysis before and after the redox reactions, Na+ insertion accompanied by H2O was presumed in the reduced state.

Metal hexacyanoferrates (MHCF) or Prussian blue analogs are excellent Cs+-adsorbents used for radioactive Cs-decontamination. However, the adsorption mechanism is controversial. To clarify the issue, we quantitatively investigated the Cs-adsorption behaviors of potassium copper hexacyanoferrate (KCuHCF) and AyCu[Fe(CN)6]1−x·zH2O. To obtain samples having homogeneous chemical composition and particle size, flow systems were used for both synthesis and purification. After sufficient rinsing with water, the range of x stable in aqueous solution in time appropriate for Cs-adsorption was 0.25 < x < 0.50. The relations y = 4 − 2x and z = 10x were also found independent of x, indicating complete dehydration of K+ in the crystal. We concluded that the excellent Cs-selectivity of MHCF was not due to difference in free energy of the adsorbed state between K+ and Cs+ but because of the hydrated state in aqueous solution. We also found that the guiding principle for determining the maximum capacity depended on the chemical composition. In particular, for the range 0.25 < x < 0.35, we propose a new model to understand the suppression of the maximum capacity. In our model, we hypothesize that Cs+ could migrate in the crystal only through [Fe(CN)6]4− vacancies. The model reproduced the observed maximum capacity without fitting parameters. The model would also be applicable to other MHCFs, e.g. a little adsorption by soluble Prussian blue. The ion exchange between Cs+ and H+ occurred only when the implemented K+ was small.

Transparent IrOx catalyst films for water oxidation were fabricated on fluorine-doped tin oxide electrodes from Ir precursor complex solutions containing Pluronic P123, Brij 58 or Pluronic F127 as surfactant structure directing agents (SDAs). The thin layers composed of highly dispersed and very small nanoparticles of ca. ≤2 nm were formed for IrOx films derived by Pluronic P123 and Brij 58, both of which act as a ‘spacer’ between the Ir-building-blocks to inhibit further agglomeration of the nanoparticles. Pluronic F127 with relatively longer hydrophilic poly(ethylene oxide) blocks stabilizes Ir-complexes in the precursor solution due to stronger interaction between its longer EO-units and Ir-complexes, affording the organized mesoporous structures of ca. 8 nm pores templated by micelles formed in the IrOx film derived by Pluronic F127. The cyclic voltammetry revealed the catalytic currents for water oxidation for the SDAs-derived IrOx films were 1.3–1.8 times higher than the IrOx film without SDA. The higher water oxidation activity observed is attributed to the higher intrinsic catalytic activity of Ir-sites on very small nanoparticles in the Pluronic P123 and Brij 58-derived IrOx films, whereas it is attributed to the increased number of active Ir-sites due to the organized mesoporous structures of the Pluronic F127-derived IrOx film.

To prepare electrically colour-switching brown and bleached devices, we investigated the electrochromism of electrodes with cobalt hexacyanoferrate (CoHCF) fabricated with a coating of ink composed of water-dispersible CoHCF nanoparticles (CoHCF-NPs). The CoHCF-NPs with surface modification with hexacyanoferrate anions were well dispersed in aqueous solution. A film shows a clear brown–bleached colour change in the presence of an applied potential switching between +1.4 V and −0.4 V. To exhibit the brown colour during electrochromism, the co-existence of a Co(III)–Fe(II) blue low spin and a Co(II)–Fe(III) red high spin state is expected to be crucially important. Hybridization of the spin states was confirmed by the shift of the infrared spectrum corresponding to the CN-vibration mode. CoHCF-NP incorporated electrochromic devices exhibiting the brown–bleached colour change were also demonstrated in combination with a counter-electrode of zinc hexacyanoferrate nanoparticles having no colour in either redox state.

Laser annealing can reduce the annealing time required to form Cu(In,Ga)(S,Se)2 (CIGSe) thin films for use in thin film photovoltaics to a single second timescale, if not faster. In this work, we use microstructural characterization coupled with modeling of the optical and thermal properties to understand the laser annealing of three types of electrodeposited precursor stacks for the CIGSe parent compound CuInSe2. The precursor films are: stacked elemental layers Cu/In/Se, stacked binary selenides In2Se3/Cu2−xSe, and a single layer of coelectrodeposited Cu–In–Se. Conceptually, these stacks are ordered in terms of decreasing stored chemical and interfacial potential free energy, consideration of which predicts that the formation of large grained CuInSe2 from the stacked elemental layers would be the most exothermic and thus most rapid process. However we find that microstructural details of the electrodeposited films such as void fraction present in the stacked binary selenides dramatically alter the heat and mass flow. Additionally, modeling of the optical absorption within the elemental stacked precursor suggests extremely localized heating at the In/Se interface resulting in significant Se loss. Despite its lower chemical potential energy, the coelectrodeposited CuInSe2 precursor's more uniform optical absorption of near-bandgap light coupled with its compact, low void fraction microstructure of nano-sized grains results in the most optimal recrystallization and compositional homogenization via interdiffusion. Furthermore this annealed layer formed a working device with a short circuit current density of 23 mA cm−2. This combined modeling and experimental investigation underscores the need to consider practical micro- and nanostructure-dependent properties as well as the optical absorption and not simply thermodynamics when designing accelerated two step deposition and annealing processes for compound semiconductors.

The related nano-chemistry has presented industrially available Prussian Blue (PB) and Prussian Blue Analogues nanoparticle (NP) inks with respect to scalability, low-cost, easy-procedure, and green productions saving energies, resources, and solvents. Mann et al. have pioneered in developing a synthetic technology for size- and morphology-controlled PB NPs using the reversed micellar method. The synthesis of PB nanowires was reported by a combination of layer-by-layer method with the anodic aluminum oxides. Dominguez-Vera et al. proposed a new chemical method for the preparation of PB NPs based on the apoferritin cavity. Prior to the rapid progress of nanotechnology and nanoscience, in 1990, Toshima et al. reported a preparation method of PB dispersion solutions, and electrochemical properties of PB thin films by a cast method. The electrochemical properties of the as-prepared PB-hexadecyltrimethylammonium chloride film were compared to those of the electrodeposited PB film.

The preparation of a hierarchically assembled Ag nanostructures based on a nanocrystalline assembly was demonstrated using an Ag(I) complex of a dipeptide (AspDap). By heating under N2 gas, a spherical assembly of a nanocrystalline dipeptide-Ag(I) complex (diameter 4-5 μm), which has a morphology similar to the assembled structure of the dipeptide, was transformed to an assembly of Ag nanostructures, where the micrometre-order crystalline morphology was maintained. In addition, detailed scanning electron microscopy studies revealed that Ag nanoparticles (diameter ca. 10 nm) were formed on the surface of the Ag nanostructure. When the Ag(I) ions were reduced to Ag(0), this phenomenon exhibited surface dependence due to the anisotropic two-dimensional Ag(I) arrangement in the crystals. Thermogravimetric measurements and X-ray photoelectron spectroscopy revealed that the reduction proceeds in a stepwise manner around 200-250 °C, together with the removal of primary and secondary carboxylic groups in the dipeptide. Comparison with the heating process of the crystalline Ag(I) complex of β-alanine indicated that stepwise reduction is key for maintaining the original micrometre-order morphology.

Polychromium-oxo-deposited TiO2 (CrIIIx Oy /TiO2 ) electrodes were fabricated by a simple electrochemical technique by using different TiO2 basal electrodes (anatase, rutile, and mixed polymorphic phases P25) as earth-abundant photoanodes for visible-light-driven water oxidation. The high-resolution transmission electron microscopy (HR-TEM) observation illustrated that an CrIIIx Oy layer with approximately 2-3 nm thickness was formed on the surface of the crystalline TiO2 particles. Upon visible-light irradiation of the electrodes, the photoanodic current based on water oxidation was generated at the CrIIIx Oy /TiO2 electrodes. However, the wavelength (below 620 nm) for photocurrent generation at CrIIIx Oy /TiO2 -rutile was longer than that (below 560 nm) at CrIIIx Oy /TiO2 -P25 by 60 nm, which is in agreement with the difference (0.2 eV) in the conduction band (CB) edge energy between rutile and anatase TiO2 . This gives a quantitative account for the photocurrent generation based on interfacial charge transfer (IFCT) from Cr 3d of the deposited CrIIIx Oy layer to the TiO2 CB. The photocurrent generated for CrIIIx Oy /TiO2 -rutile was higher than that for CrIIIx Oy /TiO2 -anatase, which is ascribed to 1) more effective CrIIIx Oy deposition on the rutile particles, 2) a larger electrolyte/CrIIIx Oy interface for water oxidation as a result of smaller rutile particles (ca. 30-40 nm) compared with larger P25 particles (ca. 40-80 nm), and 3) more effective use of visible light owing to the low energy IFCT transition of rutile.

We consider abelian CM extensions L/k of a totally real field k, and we essentially determine the Fitting ideal of the dualized Iwasawa module studied by the second author [Ku3] in the case that only places above p ramify. In doing so we recover and generalise results of loc. cit. Remarkably, our explicit description of the Fitting ideal, apart from the contribution of the usual Stickelberger element Θ at infinity, only depends on the group structure of the Galois group Gal(L/k) and not on the specific extension L. From our computation it is then easy to deduce that Ṫ Θ is not in the Fitting ideal, as soon as the p-part of Gal(L/k) is not cyclic. We need a lot of technical preparations: resolutions of the trivial module Z over a group ring, discussion of the minors of certain big matrices that arise in this context, and auxiliary results about the behaviour of Fitting ideals in short exact sequences.

A new transparent iridium oxide (IrOx) film on fluorine-doped tin oxide (FTO) electrodes were achieved from a homogeneous precursor complex solution by employing a facile spin-coating technique. The composition of the nanostructure and crystallinity of the IrOx film is tunable by a simple annealing treatment of a compact complex layer, which is responsible for their significantly different electrocatalytic performances for water oxidation. Transmission electron microscopy (TEM) observations showed uniformly dispersed small IrOx nanoparticles of dimensions ca. 2–5 nm for the film annealed at 300 °C, and the nanoparticles gradually agglomerated to form relatively large particles at higher temperatures (400 and 500 °C). The IrOx films prepared at different annealing temperatures are characterized by Raman spectroscopic data to reveal intermediate IrOx(OH)y nanoparticles with two oxygen binding motifs: terminal hydroxo and bridging oxo at 300 and 350 °C annealing, via amorphous IrOx at 400 °C, transforming ul...

Silver nanocolloid, a dense suspension of ligand-encapsulated silver nanoparticles, is an important material for printing-based device production technologies. However, printed conductive patterns of sufficiently high quality and resolution for industrial products have not yet been achieved, as the use of conventional printing techniques is severely limiting. Here we report a printing technique to manufacture ultrafine conductive patterns utilizing the exclusive chemisorption phenomenon of weakly encapsulated silver nanoparticles on a photoactivated surface. The process includes masked irradiation of vacuum ultraviolet light on an amorphous perfluorinated polymer layer to photoactivate the surface with pendant carboxylate groups, and subsequent coating of alkylamine-encapsulated silver nanocolloids, which causes amine–carboxylate conversion to trigger the spontaneous formation of a self-fused solid silver layer. The technique can produce silver patterns of submicron fineness adhered strongly to substrates, thus enabling manufacture of flexible transparent conductive sheets. This printing technique could replace conventional vacuum- and photolithography-based device processing., Silver nanocolloids are promising materials for printed electronic technologies. Here, the authors manufacture ultrafine conductive patterns utilizing the exclusive chemisorption of weakly encapsulated silver nanocolloids on a photoactivated surface.