Efficient Sb2S3 and Low Se Content Sb2SeyS3-y Indoor Photovoltaics.

Herein, the precise fabrication of Sb2S3 and low Se content Sb2SeyS3-y indoor photovoltaics is reported, and a measurement protocol for photovoltaic performance is suggested and applied. Insertion of the SnO2 buried layer decreases the thickness and parasitic absorption of the CdS layer. The introduction of minor Se into Sb2S3 and the use of spiro-OMeTAD:TMT-TTF improve the charge transport of indoor photovoltaics. Using a white light-emitting diode (LED) under illuminance of 1000, 500, and 200 lx with color temperatures of 3347 and 6103 K, indoor photovoltaics with fluorine doped tin oxide (FTO)/SnO2 (17 nm)/CdS (20 nm)/Sb2S3/spiro-OMeTAD:TMT-TTF/Au exhibit power conversion efficiency (PCE) values of 17.59, 16.66, 16.44, 16.56, 15.50, and 14.07%, respectively. Indoor photovoltaics with FTO/SnO2 (17 nm)/CdS (20 nm)/Sb2SeyS3-y(Sb/S/Se = 1:1.42:0.06)/spiro-OMeTAD:TMT-TTF/Au achieve PCE values of 18.53, 17.62, 17.07, 17.30, 16.24, and 15.38%, respectively. The PCE values of 17.59, 16.66, and 16.44% are the highest values reported for Sb2S3 indoor photovoltaics, and the other PCEs are all reported for the first time. Considering the trillion-dollar-sized market from the Internet of Things (IoT), this work can further bring an unprecedented thrust to the development of self-powered IoT devices by harvesting energy from indoor photovoltaics, thereby realizing the recycling of photon energy and reducing the use of batteries and the emission of CO2.

A2AR antagonist treatment for multiple sclerosis: Current progress and future prospects.

Emerging evidence suggests that both selective and non-selective Adenosine A2A receptor (A2AR) antagonists could effectively protect mice from experimental autoimmune encephalomyelitis (EAE), which is the most commonly used animal model for multiple sclerosis (MS) research. Meanwhile, the recent FDA approval of Nourianz® (istradefylline) in 2019 as an add-on treatment to levodopa in Parkinson's disease (PD) with "OFF" episodes, along with its proven clinical safety, has prompted us to explore the potential of A2AR antagonists in treating multiple sclerosis (MS) through clinical trials. However, despite promising findings in experimental autoimmune encephalomyelitis (EAE), the complex and contradictory role of A2AR signaling in EAE pathology has raised concerns about the feasibility of using A2AR antagonists as a therapeutic approach for MS. This review addresses the potential effect of A2AR antagonists on EAE/MS in both the peripheral immune system (PIS) and the central nervous system (CNS). In brief, A2AR antagonists had a moderate effect on the proliferation and inflammatory response, while exhibiting a potent anti-inflammatory effect in the CNS through their impact on microglia, astrocytes, and the endothelial cells/epithelium of the blood-brain barrier. Consequently, A2AR signaling remains an essential immunomodulator in EAE/MS, suggesting that A2AR antagonists hold promise as a drug class for treating MS.

The investigation of interaction and chaperon-like activity of α-synuclein as a protein in pathophysiology of Parkinson's disease upon direct interaction with tectorigenin.

Analyzing the therapeutic potential of a therapeutic biomolecule requires an understanding of how it may interact with proteins and modify their corresponding functions. α-Synuclein is a protein which is widely involved in the pathogenesis of Parkinson's disease (PD) and shows chaperon-like activity. We have selected tectorigenin, a most common methoxyisoflavone extracted from plants, among therapeutic bioactive molecules that are documented to have different therapeutic effects. Herein, we aimed to explore how tectorigenin interacts with α-synuclein in vitro by mimicking the physiological environment. Spectroscopic as well as theoretical studies including molecular docking simulation, were used to examine the effects of tectorigenin on the conformation and dynamics of α-synuclein. It was shown that tectorigenin is able to quench the protein emission spectra relied on a mixed static-dynamic quenching mechanism. Furthermore, it was displayed that tectorigenin binding to α-synuclein leads to microenvironmental changes in the tertiary structure of protein, however the protein's secondary structure was almost unchanged. It was also deduced that tectorigenin results in thermal stability of α-synuclein structure, evidenced by less perturbation of α-synuclein secondary structure following elevation of temperature in the presence of tectorigenin relative to that of free form. Molecular docking simulation demonstrated that non-covalent reactions, mainly hydrogen bonds, had a key role in the interaction and stabilization of α-synuclein in the presence of tectorigenin. Moreover, chaperon-like activity of α-synuclein was improved in the presence of tectorigenin against two model proteins, ßL-crystallin and catalase. The findings showed that tectorigenin can lead to stabilization of α-synuclein, which may be used as a therapeutic agent in prevention of neurodegenerative diseases.

Danshensu inhibits Aß aggregation and neurotoxicity as one of the main prominent features of Alzheimer's disease.

It has been found that the main cause of neurodegenerative proteinopathies, especially Alzheimer's disease (AD) is the formation of Aß amyloid plaques, which can be regulated by application of potential small molecules. In the present study, we aimed to investigate the inhibitory effect of danshensu on Aß(1-42) aggregation and relevant apoptotic pathway in neurons. A broad range of spectroscopic, theoretical, and cellular assays were done to investigate the anti-amyloidogenic characteristics of danshensu. It was found that danshensu triggers its inhibitory effect against Aß(1-42) aggregation through modulation of hydrophobic patches as well as structural and morphological changes through a stacking interaction. Furthermore, it was observed that incubation of Aß(1-42) samples with danshensu during aggregation process recovered the cell viability and mitigated the expression of caspase-3 mRNA and protein as well caspase-3 activity deregulated by Aß(1-42) amyloid fibrils alone. In general, obtained data showed that danshensu potentially inhibits Aß(1-42) aggregation and associated proteinopathies through regulation of apoptotic pathway in a concentration-dependent manner. Therefore, danshensu may be used as a promising biomolecule against the Aß aggregation and associated proteinopathies, which can be further analyzed in the future studies for the treatment of AD.

Two-dimensional triphenylene cored hole-transporting materials for efficient perovskite solar cells.

Two organic hole-transporting materials comprising a two-dimensional triphenylene core and methoxyl-arylamine terminal units are developed and applied in perovskite solar cells. Enhanced photovoltaic and stability performance are obtained using TPH-T compared with those of spiro-OMeTAD.

Anthracene-arylamine hole transporting materials for perovskite solar cells.

Two arylamine-based hole transporting materials with an anthracene π-linker have been synthesized and tested for perovskite solar cells. Improved power conversion efficiency and stability were achieved by employing A102 compared with that of spiro-OMeTAD.

Solvothermal Synthesis of Hierarchical TiO2 Microstructures with High Crystallinity and Superior Light Scattering for High-Performance Dye-Sensitized Solar Cells.

In this article, hierarchical TiO2 microstructures (HM-TiO2) were synthesized by a simple solvothermal method adopting tetra-n-butyl titanate as the titanium source in a mixed solvent composed of N,N-dimethylformamide and acetic acid. Due to the high crystallinity and superior light-scattering ability, the resultant HM-TiO2 are advantageous as photoanodes for dye-sensitized solar cells. When assembled to the entire photovoltaic device with C101 dye as a sensitizer, the pure HM-TiO2-based solar cells showed an ultrahigh photovoltage up to 0.853 V. Finally, by employing the as-obtained HM-TiO2 as the scattering layer and optimizing the architecture of dye-sensitized solar cells, both higher photovoltage and incident photon-to-electron conversion efficiency value were harvested with respect to TiO2 nanoparticles-based dye-sensitized solar cells, resulting in a high power conversion efficiency of 9.79%. This work provides a promising strategy to develop photoanode materials with outstanding photoelectric conversion performance.

Molecular Engineering of Simple Benzene-Arylamine Hole-Transporting Materials for Perovskite Solar Cells.

Three benzene-arylamine hole-transporting materials (HTMs) with different numbers of terminal groups were prepared. It is noted that the molecule with three arms (H-Tri) shows a lower highest occupied molecular orbital level and a better film morphology on perovskite layer than the molecules with two or four arms (H-Di, H-Tetra). When these molecules were applied to the perovskite solar cells, the H-Tri-based one showed better performance compared with the H-Di- or H-Tetra-based ones. Photoluminescence and impedance spectroscopy demonstrate that H-Tri can improve the hole-electron separation efficiency and decrease the charge recombination, thus leading to a better performance. Moreover, the H-Tri-based device shows a comparable performance and a much less materials cost than the conventional spiro-OMeTAD. Therefore, we have presented a new low-cost and high-performance HTM through simple molecular engineering.

Enhancing the Photovoltaic Performance of Perovskite Solar Cells with a Down-Conversion Eu-Complex.

Organometal halide perovskite solar cells (PSCs) have shown high photovoltaic performance but poor utilization of ultraviolet (UV) irradiation. Lanthanide complexes have a wide absorption range in the UV region and they can down-convert the absorbed UV light into visible light, which provides a possibility for PSCs to utilize UV light for higher photocurrent, efficiency, and stability. In this study, we use a transparent luminescent down-converting layer (LDL) of Eu-4,7-diphenyl-1,10-phenanthroline (Eu-complex) to improve the light utilization efficiency of PSCs. Compared with the uncoated PSC, the PSC coated with Eu-complex LDL on the reverse of the fluorine-doped tin oxide glass displayed an enhancement of 11.8% in short-circuit current density (Jsc) and 15.3% in efficiency due to the Eu-complex LDL re-emitting UV light (300-380 nm) in the visible range. It is indicated that the Eu-complex LDL plays the role of enhancing the power conversion efficiency as well as reducing UV degradation for PSCs.

Tetraphenylmethane-Arylamine Hole-Transporting Materials for Perovskite Solar Cells.

A new class of hole-transporting materials (HTM) containing tetraphenylmethane (TPM) core have been developed. After thermal, charge carrier mobility, and contact angle tests, it was found that TPA-TPM (TPA: arylamine derivates side group) showed higher glass-transition temperature and larger water-contact angle than spiro-OMeTAD with comparable hole mobility. Photoluminescence and impedance spectroscopy studies indicate that TPA-TPM's hole-extraction ability is comparable to that of spiro-OMeTAD. SEM and AFM results suggest that TPA-TPM has a smooth surface. When TPA-TPM is used in mesoscopic perovskite solar cells, power conversion efficiency comparable to that of spiro-OMeTAD is achieved. Notably, the perovskite solar cells employing TPA-TPM show better long-term stability than that of spiro-OMeTAD. Moreover, TPA-TPM can be prepared from relatively inexpensive raw materials with a facile synthetic route. The results demonstrate that TPM-arylamines are a new class of HTMs for efficient and stable perovskite solar cells.

Superior Light-Harvesting Heteroleptic Ruthenium(II) Complexes with Electron-Donating Antennas for High Performance Dye-Sensitized Solar Cells.

Three heteroleptic polypyridyl ruthenium complexes, RC-41, RC-42, and RC-43, with efficient electron-donating antennas in the ancillary ligands were designed, synthesized, and characterized as sensitizers for dye-sensitized solar cell. All the RC dye sensitizers showed remarkable light-harvesting capacity and broadened absorption range. Significantly, RC-43 obtained the lower energy metal-ligand charge transfer (MLCT) band peaked at 557 nm with a high molar extinction coefficient of 27 400 M(-1) cm(-1). In conjunction with TiO2 photoanode of submicrospheres and iodide-based electrolytes, the DSSCs sensitizing with the RC sensitizers, achieved impressively high short-circuit current density (19.04 mA cm(-2) for RC-41, 19.83 mA cm(-2) for RC-42, and 20.21 mA cm(-2) for RC-43) and power conversion efficiency (10.07% for RC-41, 10.52% for RC-42, and 10.78% for RC-43). The superior performances of RC dye sensitizers were attributed to the enhanced light-harvesting capacity and incident-photon-to-current efficiency (IPCE) caused by the introduction of electron-donating antennas in the ancillary ligands. The interfacial charge recombination/regeneration kinetics and electron lifetime were further evaluated by the electrochemical impedance spectroscopy (EIS) and transient absorption spectroscopy (TAS). These data decisively revealed the dependences on the photovoltaic performance of ruthenium sensitizers incorporating electron-donating antennas.

Effect of electron-donor ancillary ligands on the heteroleptic ruthenium complexes: synthesis, characterization, and application in high-performance dye-sensitized solar cells.

Three heteroleptic ruthenium complexes, RC-15, RC-16 and RC-22, with sulfur- or oxygen-containing electron-donor, phenylpyridine-based ancillary ligands, are synthesized. The influence of the different electron donors-the acyclic electron donors methylthio and methoxyl, and the cyclic electron donor methylenedioxy-on the photophysical and electrochemical behavior in dye sensitizers and photovoltaic performance in DSSCs are investigated. Compared to the conventional dye N3, all the dyes demonstrate superior performance in the form of molar absorptivity, photocurrent density (J(SC)) and conversion efficiency (η). The DSSCs based on RC-15 and RC-16, with only a two-atom change in the acyclic electron donor, exhibit analogous photovoltaic performance (9.28% for RC-15 and 9.32% for RC-16). The highest photocurrent density (19.06 mA cm(-2)) and conversion efficiency (9.74%) are recorded for RC-22, which contains the cyclic electron donor. Transient absorption (TAS) and time-resolved photoluminescence (TRPL) measurements are carried out to investigate the sensitizers' regeneration and the behavior of excited electron decay kinetics. Furthermore, electrochemical impedance spectroscopy (EIS) is operated to explain the charge recombination and the electron lifetime. These consequences reveal substantial dependences on the different configurations of the electron-donor ancillary ligands.

Mesoporous TiO2 Yolk-Shell Microspheres for Dye-sensitized Solar Cells with a High Efficiency Exceeding 11%.

Yolk-shell TiO2 microspheres were synthesized via a one-pot template-free solvothermal method building on the aldol condensation reaction of acetylacetone. This unique structure shows superior light scattering ability resulting in power conversion efficiency as high as 11%. This work provided a new synthesis system for TiO2 microspheres from solid to hollow and a novel material platform for high performance solar cells.

One-Pot Synthesis of Mesoporous TiO2 Micropheres and Its Application for High-Efficiency Dye-Sensitized Solar Cells.

TiO2 microspheres are of great interest for a great deal of applications, especially in the solar cell field. Because of their unique microstructure and light-scattering effect, TiO2 microsphere-based solar cells often exhibit superior photovoltaic performance. Hence, exploring new suitable TiO2 microspheres for high-efficiency solar cells is essential. In this work, we demonstrate a facile one-pot solvothermal approach for synthesis of TiO2 microspheres using acetone as solvent. The as-prepared TiO2 microspheres are composed of densely interconnected nanocrystals and possess a high specific surface area up to 138.47 m(2) g(-1). As the photoanode, the TiO2 microsphere-based DSSC gives higher dye loading and light adsorption ability as well as longer electron lifetime, resulting in higher short-circuit current value and superior power conversion efficiency (PCE) compared with Dyesol 18 nm TiO2 nanoparticle paste. Finally, the TiO2 microsphere-based DSSC were optimized by adding a TiO2 nanocrystal underlayer and TiCl4 post-treatment, giving a high PCE of 10.32%.