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With [RuII(bpyMeP)2tpphzPtCl2]2+ (4) a molecular photocatalyst has been synthesized for visible-light-driven H2-evolution. It contains the ligand bpyMeP (4,4′-bis(diethyl-(methylene)-phosphonate)-2,2′-bipyridine) with phosphate ester groups as precursors for the highly potent phosphonate anchoring groups, which can be utilized for immobilization of the catalyst on metal–oxide semiconductor surfaces. The synthesis was optimized with regard to high yields, bpyMeP was fully characterized and a solid-state structure could be obtained. Photophysical studies showed that the photophysical properties and the localization of the excited states are not altered compared to similar Ru-complexes without anchoring group precursors. (4) was even more active in homogenous catalysis experiments than [RuII(tbbpy)2tpphzPtCl2]2+ (6) with tbbpy (4,4′-bis(tbutyl)-2,2′-bipyridine) as peripheral ligands. After hydrolysis (4) was successfully immobilized on NiO, suggesting that an application in photoelectrosynthesis cells is feasible. [ABSTRACT FROM AUTHOR]

Organic–inorganic halide perovskite(OIHP) compounds arevery interesting materials for device application in, for example,solar cells, electro-optics, and electronic circuits. In this report,we investigated OIHPs reported as CH3NH3PbI3–xClx(MAPbI3–xClx)and CH3NH3PbI3(MAPbI3) prepared from solution on mesoporous TiO2/glass substrates.A long-term conversion from disordered to more crystalline OIHPs wasobserved for both types of samples from XRD patterns over 5 weeks.The conversion rate to more crystalline OIHPs could be increased byincreasing the temperature of the sample. SEM analyses of the twotypes of OIHPs show remarkably different surface microstructures.The X-ray diffractograms suggest that both samples are dominated bythe similar crystal structure, although the preferential orientationfor the crystal structure is different. Moreover, the results suggestthat the material reported as MAPbI3–xClxis a combination of MAPbI3and MAPbCl3. The crystal structure and exact natureof the material is important for the understanding and optimizationof devices, and the possibility for enhanced crystallinity of theOIHPs shown in this report will therefore be important for furtherimprovement and understanding of the devices. [ABSTRACT FROM AUTHOR]

Mixed lead‐tinv halide (LTH) perovskite solar cells (LTH‐PSCs) can reduce the toxicity concerns of full lead‐based PSCs and potentially optimize the bandgap to maximize efficiency. However, commonly used hole‐transporting material (HTM) 2,2′,7,7′‐tetrakis(N,N‐di‐p‐methoxyphenyl‐amine)9,9′‐spirobifluorene (Spiro‐OMeTAD) with additional dopants Li‐bis(trifluoromethanesulfonyl) imide (Li‐TFSI) and 4‐tert‐butylpyridine (t‐BP) deteriorate oxidation Sn2+ to Sn4+ leading to trap formation. Here, the study introduces a novelty Sn‐friendly HTM for Sn‐rich LTH‐PSCs, combining Spiro‐OMeTAD with 4‐Isopropyl‐4′‐methyldiphenyliodonium tetrakis(pentafluorophenyl)borate (dpi‐TPFB) as a dopant and blended with poly(3‐hexylthiophene‐2,3‐diyl) (P3HT). This blended HTM avoids the harmful effects of Li‐TFSI and t‐BP dopants and leverages the beneficial hydrophobic properties of P3HT, which predominantly resides on the surface with a face‐on orientation. This arrangement not only enhances charge transport and extraction but also improves device stability by protecting the perovskite from environmental factors. Optimizing the P3HT concentration of blended HTM achieved a PCE of 17.27%, the highest reported for n‐i‐p structured Sn‐rich mixed LTH‐PSCs. This HTM also significantly improved device stability, maintaining over 90% of the initial PCE after 3000 h of storage and 80% under maximum power point tracking (MPPT) for 550 h in the air. [ABSTRACT FROM AUTHOR]

Tin sulfide (SnS) is one of the most promising solar cell materials, as it is abundant, environment friendly, available at low cost, and offers long‐term stability. However, the highest efficiency of the SnS solar cell reported so far remains at 4.36% even using the expensive atomic layer deposition process. This study reports on the fabrication of SnS solar cells by a solution process that employs rapid thermal treatment for few seconds under Ar gas flow after spin‐coating a precursor solution of SnCl2 and thiourea dissolved in dimethylformamide onto a nanostructured thin TiO2 electrode. The best‐performing cell exhibits power conversion efficiency (PCE) of 3.8% under 1 sun radiation conditions (AM1.5G). Moreover, secondary treatment using SnCl2 results in a significant improvement of 4.8% in PCE, which is one of the highest efficiencies among SnS‐based solar cells, especially with TiO2 electrodes. The thin film properties of SnS after SnCl2 secondary treatment are analyzed using grazing‐incidence wide‐angle X‐ray scattering, and high‐resolution transmittance electron microscopy. [ABSTRACT FROM AUTHOR]

In view of the possible replacement of toxic lead perovskites in solar cells by a less toxic electrode material, Bi-based perovskites A3Bi2I9 (A: MeNH3, Cs) are synthesized by reaction of metallic Cs or MeNH3I with BiI3 in a 7:3 DMF/DMSO mixture. [ABSTRACT FROM AUTHOR]

We report a hybrid dye system, in which two dyes are linked linearly by a metal–O–metal linkage, for dye sensitized solar cells (cell-NcSn-N719). Tin(IV) 2,11,20,29-tetra-tert-butyl-2,3-naphthalocyanine (NcSn) was adsorbed on a SnO2 surface by a Sn(p)–O–Sn(n) linkage, where Sn(p) and Sn(n) stand for a Sn atom on a Sn nanoparticle surface and that at the center of NcSn, respectively. cis-Diisothiocyanato-bis(2,2'-bipyridyl-4,4'-dicarboxylato)ruthenium(II) bis(tetrabutylammonium), known as N719, was bonded to NcSn by a –Sn(n)–O–CO– linkage. The incident photon to photocurrent efficiency (IPCE) curve of cell-NcSn-N719 suggested that electrons are injected from both N719 and NcSn to SnO2 nanoparticles. [ABSTRACT FROM AUTHOR]

Controlling autonomous propulsion of microswimmers is essential for targeted drug delivery and applications of micro/nanomachines in environmental remediation and beyond. Herein, we report two-dimensional (2D) carbon nitride-based Janus particles as highly efficient, light-driven microswimmers in aqueous media. Due to the superior photocatalytic properties of poly(heptazine imide) (PHI), the microswimmers are activated by both visible and ultraviolet (UV) light in conjunction with different capping materials (Au, Pt, and SiO 2 ) and fuels (H 2 O 2 and alcohols). Assisted by photoelectrochemical analysis of the PHI surface photoreactions, we elucidate the dominantly diffusiophoretic propulsion mechanism and establish the oxygen reduction reaction (ORR) as the major surface reaction in ambient conditions on metal-capped PHI and even with TiO 2 -based systems, rather than the hydrogen evolution reaction (HER), which is generally invoked as the source of propulsion under ambient conditions with alcohols as fuels. Making use of the intrinsic solar energy storage ability of PHI, we establish the concept of photocapacitive Janus microswimmers that can be charged by solar energy, thus enabling persistent light-induced propulsion even in the absence of illumination-a process we call "solar battery swimming"-lasting half an hour and possibly beyond. We anticipate that this propulsion scheme significantly extends the capabilities in targeted cargo/drug delivery, environmental remediation, and other potential applications of micro/nanomachines, where the use of versatile earth-abundant materials is a key prerequisite., Competing Interests: The authors declare no competing interest., (Copyright © 2020 the Author(s). Published by PNAS.)

While current light-driven microswimmers require high-intensity light, UV light, or toxic fuels to propel them, powering them with low-intensity UV-free visible light without fuels is essential to enable their potential high-impact applications. Therefore, in this study, a new material for light-driven microswimmers in the form of CoO is introduced. Janus CoO-TiO 2 microswimmers powered with low-intensity, UV-free visible light inside water without using any toxic fuels like H 2 O 2 is proposed. The microswimmers show propulsion under full spectrum of visible light with 17 times lower intensity than the mean solar intensity. They propel by breaking down water into oxygen and oxide radicals, which enables their potential applications for photocatalysis and drug delivery. The microswimmers are multiwavelength responsive, from the ultraviolet to the infrared region. The direction of swimming changes with the change in the illumination from the visible to UV light. In addition to being responsive, they are wavelength steerable and exhibit inherent magnetic properties enabling magnetic steering control of the CoO-TiO 2 microswimmers. Thus, these microswimmers, which are propelled under low-intensity visible light, have direction-changing capability using light of different wavelengths, and have steering control capability by external magnetic fields, could be used in future potential applications, such as active and local cargo delivery, active photocatalysis, and hydrogen evolution.

Background: Traditional Korean medicine (TKM) is widely used to treat children with cerebral palsy (CP) in Korea; however, studies investigating factors that influence the use of TKM are scarce. Thus, we investigated the clinical factors that might influence the use of TKM., Methods: A population-based, cross-sectional, multicenter survey was performed from August 2014 to May 2016. The history of TKM use, type and severity of CP, current treatment characteristics, presence of accompanying disabilities or other health problems not directly related to CP, and monthly cost for the treatment of CP were surveyed., Results: In total, 182 children were recruited, and 78 children (42.9%) had used TKM. Among these 78 children, 50 (64.1% of the TKM-use group) had used both acupuncture and herbal medication, 15 (19.2%) had used acupuncture only, and 13 (16.7%) had used herbal medication only. Children with non-typical CP, accompanying disabilities and general health problems tended to use TKM. The monthly cost of treatment for CP was significantly higher in the TKM-use group than that in the no-TKM-use group, suggesting that economically disadvantaged children may have difficulty in accessing TKM. Dietary supplements, conventional pharmacological treatments, and rehabilitation therapies did not affect TKM use., Conclusion: Children with non-typical symptoms or those with poor overall health status are likely to use TKM. Additionally, TKM use leads to increased treatment costs. Studies investigating the motivation for starting or ceasing TKM therapy, socioeconomic factors and the attitude of parents towards complementary and alternative medicine should be performed.

The presence of excess lead iodide in halide perovskites has been key for surpassing 20% photon-to-power conversion efficiency. To achieve even higher power conversion efficiencies, it is important to understand the role of remnant lead iodide in these perovskites. To that end, we explored the mechanism facilitating this effect by identifying the impact of excess lead iodide within the perovskite film on charge diffusion length, using electron-beam-induced current measurements, and on film formation properties, from grazing-incidence wide-angle X-ray scattering and high-resolution transmission electron microscopy. Based on our results, we propose that excess lead iodide in the perovskite precursors can reduce the halide vacancy concentration and lead to formation of azimuthal angle-oriented cubic α-perovskite crystals in-between 0° and 90°. We further identify a higher perovskite carrier concentration inside the nanostructured titanium dioxide layer than in the capping layer. These effects are consistent with enhanced lead iodide-rich perovskite solar cell performance and illustrate the role of lead iodide.

Objectives: To determine the differential expressions of nucleotide oligomerisation domain (NOD)-like receptors (NLRs) and to investigate their association with inflammatory responses in rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS)., Methods: Gene expression and protein levels of various NLRs, including NOD1, NOD2, NLRP1, NLRP3, NLRP12, NLRX1, and NLRC3, were determined in FLS and synovial tissues from patients with RA and patients with osteoarthritis (OA) using quantitative real-time PCR and immunohistochemistry. After transfection of NOD2 RNAi plasmids or a pcDNA3.1-NLRX1 vector, gene expression levels of pro-inflammatory cytokines in RA FLS and the protein levels of these cytokines in culture supernatants were determined using quantitative real-time PCR and enzyme-linked immunosorbent assays. The effects of NLR gene regulation on NF-κB and caspase-1 were evaluated using Western blot analysis., Results: Gene expression levels of NOD1, NLRP1, NLRP3, NLRP12, and NLRC3 were not different between RA and OA samples. NOD2 gene expression and protein levels were significantly increased in RA samples, whereas the levels of NLRX1 were significantly decreased. Downregulation of NOD2 gene expression by transfection with NOD2 RNAi plasmid significantly reduced pro-inflammatory cytokine levels in RA FLS, while transfection with adenoviral vectors encoding NLRX1 had no effect on pro-inflammatory cytokine levels. Downregulation of NOD2 gene expression significantly decreased NF-κB, TRAF6, and IKK levels, but not caspase-1 levels, in RA FLS., Conclusions: NOD2 is upregulated in RA FLS; moreover, downregulation of NOD2 gene expression reduces pro-inflammatory cytokine and NF-κB levels in RA FLS. These findings provide evidence that NOD2 exerts pro-inflammatory effects in RA.

The formation of a dense and uniform thin layer on the substrates is crucial for the fabrication of high-performance perovskite solar cells (PSCs) containing formamidinium with multiple cations and mixed halide anions. The concentration of defect states, which reduce a cell's performance by decreasing the open-circuit voltage and short-circuit current density, needs to be as low as possible. We show that the introduction of additional iodide ions into the organic cation solution, which are used to form the perovskite layers through an intramolecular exchanging process, decreases the concentration of deep-level defects. The defect-engineered thin perovskite layers enable the fabrication of PSCs with a certified power conversion efficiency of 22.1% in small cells and 19.7% in 1-square-centimeter cells., (Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

This paper describes the application of the atomic force microscopy (AFM) as a nano-indentation method and introduces a new method of identifying the chronological order of the application of the toner and stamping ink on the surface of documents by removing either of them. Various toners were used as samples for the AFM nano-indentation method. The chronological order of the application of the toner and stamping ink with either the toner placed over the stamping ink or the stamping ink placed over the toner, could be identified, regardless of the kinds of toners made by various companies. This paper provides the new approach for physically removing the toner and checking the material below it to identify questioned documents, which allows the method to be used to appraise documents forensically. Blind testing has shown that the method to analyze the chronological order of toner-printed documents and the seal stamping on them could accurately identify the order in all samples, while minimizing damage to the samples., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Low-toxic bismuth-based perovskites are prepared for the possible replacement of lead perovskite in solar cells. The perovskites have a hexagonal crystalline phase and light absorption in the visible region. A power conversion efficiency of over 1% is obtained for a solar cell with Cs3 Bi2 I9 perovskite, and it is concluded that bismuth perovskites have very promising properties for further development in solar cells., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)