Conspectus During the last few decades, the design of catalytic systems for CO2 reduction has been extensively researched and generally involves (1) traditional approaches using molecular ...organic/organometallic materials and heterogeneous inorganic semiconductors and (2) combinatory approaches wherein these materials are combined as needed. Recently, we have devised a number of new TiO2-mediated multicomponent hybrid systems that synergistically integrate the intrinsic merits of various materials, namely, molecular photosensitizers/catalysts and n-type TiO2 semiconductors, and lower the energetic and kinetic barriers between components. We have termed such multicomponent hybrid systems assembled from the hybridization of various organic/inorganic/organometallic units in a single platform inorganometallic photocatalysts. The multicomponent inorganometallic (MIOM) hybrid system onto which the photosensitizer and catalyst are coadsorbed efficiently eliminates the need for bulk-phase diffusion of the components and avoids the accumulation of radical intermediates that invokes a degradation pathway, in contrast to the homogeneous system, in which the free reactive species are concentrated in a confined reaction space. In particular, in energetic terms, we discovered that in nonaqueous media, the conduction band (CB) levels of reduced TiO2 (TiO2(e–)) are positioned at a higher level (in the range −1.5 to −1.9 V vs SCE). This energetic benefit of reduced TiO2 allows smooth electron transfer (ET) from injected electrons (TiO2(e–)) to the coadsorbed CO2 reduction catalyst, which requires relatively high reducing power (at least more than −1.1 V vs SCE). On the other hand, the existence of various shallow surface trapping sites and surface bands, which are 0.3–1.0 eV below the CB of TiO2, efficiently facilitates electron injection from any photosensitizer (including dyes having low excited energy levels) to TiO2 without energetic limitation. This is contrasted with most photocatalytic systems, wherein successive absorption of single high-energy photons is required to produce excited states with enough energy to fulfill photocatalytic reaction, which may allow unwanted side reactions during photocatalysis. In this Account, we present our recent research efforts toward advancing these MIOM hybrid systems for photochemical CO2 reduction and discuss their working mechanisms in detail. Basic ET processes within the MIOM system, including intervalence ET in organic/organometallic redox systems, metal-to-ligand charge transfer of organometallic complexes, and interfacial/outer-sphere charge transfer between components, were investigated by conducting serial photophysical and electrochemical analyses. Because such ET events occur primarily at the interface between the components, the efficiency of interfacial ET between the molecular components (organic/organometallic photosensitizers and molecular reduction catalysts) and the bulk inorganic solid (mainly n-type TiO2 semiconductors) has a significant influence on the overall photochemical reaction kinetics and mechanism. In some TiO2-mediated MIOM hybrids, the chemical attachment of organic or organometallic photosensitizing units onto TiO2 semiconductors efficiently eliminates the step of diffusion/collision-controlled ET between components and prevents the accumulation of reactive species (oxidatively quenched cations or reductively quenched anions) in the reaction solution, ensuring steady photosensitization over an extended reaction period. The site isolation of a single-site organometallic catalyst employing TiO2 immobilization promotes the monomeric catalytic pathway during the CO2 reduction process, resulting in enhanced product selectivity and catalytic performance, including lifetime extension. In addition, as an alternative inorganic solid scaffold, the introduction of a host porphyrin matrix (interlinked in a metal–organic framework (MOF) material) led to efficient and durable photocatalytic CO2 conversion by the new MOF–Re(I) hybrid as a result of efficient light harvesting/exciton migration in the porphyrinic MOF and rapid quenching of the photogenerated electrons by the doped Re(I) catalytic sites. Overall, the case studies presented herein provide valuable insights for the rational design of advanced multicomponent hybrid systems for artificial photosynthesis involving CO2 reduction.
Currently, wind energy harvesting is in the limelight. However, with the existing electromagnetic wind generators, it is difficult to harvest multifariously‐wasted breezes. To harvest energy from ...winds at a wide range of speeds, wind‐driven triboelectric nanogenerators (TENGs) are studied. However, a critical limitation of general wind‐driven TENGs is that their power output is low. Therefore, an innovative strategy is necessary to generate high output power even from breeze. Herein, an approach to test a charge‐polarization‐based flutter‐driven TENG (CPF‐TENG) with ambient air ionizing channel (AAIC) is reported. Owing to AAIC, the device generates peak voltage and current outputs of 2000 V and 4 A, respectively. Moreover, because the proposed CPF‐TENG can generate power from breeze, it can be stacked in series to completely harvest wind energy. The stacked CPF‐TENG is demonstrated to operate 3000 light‐emitting diodes (LEDs) and 12 hygrometers, separately, and produce hydrogen at a rate of 342.3 µL h−1 with the electrolysis cell.
It is demonstrated charge‐polarization‐based flutter‐driven triboelectric nanogenerator (CPF‐TENG) that can generate high electrical output by utilizing ambient air ionizing channel (AAIC) is fabricated. Even with low velocity wind input, CPF‐TENG with AAIC can generate high electrical output so the stacked device can completely harvest unidirectional wind energy. Consequently, the device can turn on several electronics and produce 342.3 µL h−1 of hydrogen.
Because of their efficient energy-transport properties, porphyrin-based metal–organic frameworks (MOFs) are attractive compounds for solar photochemistry applications. However, their absorption bands ...provide limited coverage in the visible spectral range for light-harvesting applications. We report here the functionalization of porphyrin-based MOFs with CdSe/ZnS core/shell quantum dots (QDs) for the enhancement of light harvesting via energy transfer from the QDs to the MOFs. The broad absorption band of the QDs in the visible region offers greater coverage of the solar spectrum by QD–MOF hybrid structures. We show through time-resolved emission studies that photoexcitation of the QDs is followed by energy transfer to the MOFs with efficiencies of more than 80%. This sensitization approach can result in a >50% increase in the number of photons harvested by a single monolayer MOF structure with a monolayer of QDs on the surface of the MOF.
We report the synthesis and characterization of two thin films (DA-MOF and L2-MOF) of porphyrin-based MOFs on functionalized surfaces using a layer-by-layer (LbL) approach. Profilometry measurements ...confirm that the film thickness increases systematically with number of growth cycles. Polarization excitation and fluorescence measurements indicate that the porphyrin units are preferentially oriented, while X-ray reflectivity scans point to periodic ordering. Ellipsometry measurements show that the films are highly porous. Since there are currently few methods capable of yielding microporous MOFs containing accessible free-base porphyrins, it is noteworthy that the LbL growth permits direct MOF incorporation of unmetalated porphyrins. Long-range energy transfer is demonstrated for both MOF films. The findings offer useful insights for subsequent fabrication of MOF-based solar energy conversion devices.
Successive cold winters of severely low temperatures in recent years have had critical social and economic impacts on the mid-latitude continents in the Northern Hemisphere. Although these cold ...winters are thought to be partly driven by dramatic losses of Arctic sea-ice, the mechanism that links sea-ice loss to cold winters remains a subject of debate. Here, by conducting observational analyses and model experiments, we show how Arctic sea-ice loss and cold winters in extra-polar regions are dynamically connected through the polar stratosphere. We find that decreased sea-ice cover during early winter months (November-December), especially over the Barents-Kara seas, enhances the upward propagation of planetary-scale waves with wavenumbers of 1 and 2, subsequently weakening the stratospheric polar vortex in mid-winter (January-February). The weakened polar vortex preferentially induces a negative phase of Arctic Oscillation at the surface, resulting in low temperatures in mid-latitudes.
•IRB/AML fixed-dose regimens show superior antihypertensive efficacy over IRB monotherapy.•A potential benefit of IRB/AML regimens was noted in the elderly and T2DM patients.•IRB/AML combinations are ...well-tolerated and have comparable safety to IRB monotherapy.
This study aimed to evaluate the efficacy and tolerability of irbesartan (IRB) and amlodipine (AML) combination therapy in patients with essential hypertension whose blood pressure (BP) was not controlled by IRB monotherapy.
Two multicenter, randomized, double-blind, placebo-controlled, phase III studies were conducted in Korea (the I-DUO 301 study and the I-DUO 302 study). After a 4-week run-in period with either 150 mg IRB (I-DUO 301 study) or 300 mg IRB (I-DUO 302 study), patients with uncontrolled BP (ie, mean sitting systolic BP MSSBP ≥140 mmHg to <180 mmHg and mean sitting diastolic BP <110 mmHg) were randomized to the placebo, AML 5 mg, or AML 10 mg group. A total of 428 participants were enrolled in the 2 I-DUO studies. In the I-DUO 301 study, 271 participants were randomized in a 1:1:1 ratio to receive either IRB/AML 150/5 mg, IRB/AML 150/10 mg, or IRB 150 mg/placebo. In the I-DUO 302 study, 157 participants were randomized in a 1:1 ratio to receive IRB/AML 300/5 mg or IRB 300 mg/placebo. The primary endpoint was the change in MSSBP from baseline to week 8. Tolerability was assessed according to the development of treatment-emergent adverse events (TEAEs) and clinically significant changes in physical examination, laboratory tests, pulse, and 12-lead electrocardiography.
In I-DUO 301, the mean (SD) changes of MSSBP at week 8 from baseline were −14.78 (12.35) mmHg, −21.47 (12.78) mmHg, and −8.61 (12.19) mmHg in the IRB/AML 150/5 mg, IRB/AML 150/10 mg, and IRB 150 mg/placebo groups, respectively. In I-DUO 302, the mean (SD) changes of MSSBP at week 8 from baseline were −13.30 (12.47) mmHg and −7.19 (15.37) mmHg in the IRB/AML 300/5 mg and IRB 300 mg/placebo groups, respectively. In both studies, all combination groups showed a significantly higher reduction in MSSBP than the IRB monotherapy groups (P < 0.001 for both). TEAEs occurred in 10.00%, 10.99%, and 12.22% of participants in the IRB/AML 150/5 mg, IRB/AML 150/10 mg, and IRB 150 mg/placebo groups, respectively, in I-DUO 301 and in 6.33% and 10.67% of participants in the IRB/AML 300/5 mg and IRB 300 mg/placebo groups, respectively, in I-DUO 302, with no significant between-group differences. Overall, there was one serious adverse event throughout I-DUO study.
The combination of IRB and AML has superior antihypertensive effects compared with IRB alone over an 8-week treatment period, with placebo-like tolerability.
ClinicalTrials.gov identifier: NCT05476354 (I-DUO 301), NCT05475665 (I-DUO 302).
Red light-sensitized squaraine (SQ) dyes were developed and incorporated into dye-sensitized catalysts (DSCs) with the formula of SQ/TiO2/Cat, and their efficacies were evaluated in terms of ...performance on either water or carbon dioxide reduction. Pt nanoparticles or fac-Re(4,4′-bis-(diethoxyphosphorylmethyl)-2,2′-bipyridine)(CO)3Cl were used as each catalytic center within the DSC frame of SQ/TiO2/Pt (Type I) or SQ/TiO2/Re(I) (Type II). In order to convey the potential utility of SQ in low energy sensitization, the following catalytic reductions were carried out under selective lower energy irradiation (>500 nm). Type I and II showed different catalytic performances, primarily due to the choice of solvent for each catalytic condition: hydrogenation was carried out in H2O, but CO2 reduction in dimethylformamide (DMF), and SQ was more stable in aqueous acid conditions for hydrogen generation than CO2 reduction in DMF. A suspension of Type I in 3 mL water containing 0.1 M ascorbic acid (pH = 2.66) resulted in efficient photocatalytic hydrogen evolution, producing 37 μmol of H2 for 4 h. However, in photocatalysis of Type II (SQ/TiO2/Re(I)) in 3 mL DMF containing 0.1 M 1,3-dimethyl-2-phenyl-1,3-dihydrobenzimidazole, the TiO2-bound SQ dyes were not capable of working as a low energy sensitizer because SQ was susceptible to dye decomposition in nucleophilic DMF conditions, resulting in DSC deactivation for the CO2 reduction. Even with the limitation of solvent, the DSC conditions for the utility of SQ have been established: the anchoring group effect of SQ with either phosphonic acid or carboxylic acid onto the TiO2 surface; energy alignment of SQ with the flat band potentials (E fb) of TiO2 semiconductors and the reduction power of electron donors; and the wavelength range of the light source used, particularly when >500 nm.
For triboelectric nanogenerators (TENGs), achieving both high root‐mean‐square (RMS) current output and portability remains a challenge. Here, a charge‐accumulating‐flutter‐based triboelectric ...nanogenerator (CAF‐TENG) with ultrahigh RMS current and average power density/portability is proposed. Because of the electron accumulation/discharge mechanism and electrical/mechanical flutter device design, the CAF‐TENG can generate an RMS voltage, RMS current, and average power density of 44 V, 36 mA, and 26 mW cm−3, respectively. The CAF‐TENG is optimized via quantitative electrical/mechanical analysis. CAF‐TENG can power an array of 2000 commercial LEDs continuously and charge high‐capacitance capacitors/commercial lithium batteries. Furthermore, as a practical application, a mask‐valve‐integrated CAF‐TENG is fabricated, which can power eight commercial lamps (5 W) continuously and operate a commercial Bluetooth tracker by charging a capacitor in a daily respiration scenario.
The charge‐accumulating‐flutter‐based triboelectric nanogenerator (CAF‐TENG) exhibits an outstanding output performance and portability owing to the proposed charge accumulation‐discharge mechanism and mechanical design/compact size. Furthermore, a mask‐valve‐integrated CAF‐TENG can power eight commercial lamps (rated power of one lamp: 5 W) and operate a Bluetooth tracker in a daily respiration scenario.
We report the one-pot synthesis of colloidal Mn-doped cesium lead halide (CsPbX3) perovskite nanocrystals and efficient intraparticle energy transfer between the exciton and dopant ions resulting in ...intense sensitized Mn luminescence. Mn-doped CsPbCl3 and CsPb(Cl/Br)3 nanocrystals maintained the same lattice structure and crystallinity as their undoped counterparts with nearly identical lattice parameters at ∼0.2% doping concentrations and no signature of phase separation. The strong sensitized luminescence from d–d transition of Mn2+ ions upon band-edge excitation of the CsPbX3 host is indicative of sufficiently strong exchange coupling between the charge carriers of the host and dopant d electrons mediating the energy transfer, essential for obtaining unique properties of magnetically doped quantum dots. Highly homogeneous spectral characteristics of Mn luminescence from an ensemble of Mn-doped CsPbX3 nanocrystals and well-defined electron paramagnetic resonance spectra of Mn2+ in host CsPbX3 nanocrystal lattices suggest relatively uniform doping sites, likely from substitutional doping at Pb2+. These observations indicate that CsPbX3 nanocrystals, possessing many superior optical and electronic characteristics, can be utilized as a new platform for magnetically doped quantum dots expanding the range of optical, electronic, and magnetic functionality.
Objective
To examine the associations between the allergic triad (asthma, allergic rhinitis, atopic dermatitis) and risk of dementia.
Methods
Participants comprised 6,785,948 adults aged ≥40 years ...who participated in a national health examination in 2009 without any history of dementia before baseline. From 2009 to 2017, we prospectively investigated the associations between physician‐diagnosed allergic diseases and risk of incident dementia (all‐cause, Alzheimer's disease AD, vascular dementia VaD) ascertained using national health insurance claims data.
Results
During 8.1 years of follow‐up, 260,705 dementia cases (195,739 AD, 32,789 VaD) were identified. Allergic diseases were positively associated with dementia risk. Compared with individuals without allergic diseases, multivariable hazard ratios (HRs) of all‐cause dementia were 1.20 (95% confidence interval CI 1.19–1.22) in those with asthma, 1.10 (95% CI 1.09–1.12) with allergic rhinitis, 1.16 (95% CI 1.11–1.21) with atopic dermatitis, and 1.13 (95% CI 1.12–1.14) with any of these allergies. Similarly, individuals with any of the allergic triad had a higher risk of AD (HR 1.16, 95% CI 1.14–1.17) and VaD (HR 1.04; 95% CI 1.01–1.06) than those without any allergic disease. As the number of comorbid allergic diseases increased, the risk of dementia increased linearly (Ptrend ≤ 0.002). Compared with individuals without allergies, those with all three allergic diseases had substantially increased risk of all‐cause dementia (HR 1.54, 95% CI 1.35–1.75), AD (HR 1.46; 95% CI 1.25–1.70), and VaD (HR 1.99, 95% CI 1.44–2.75).
Interpretation
Asthma, allergic rhinitis, and atopic dermatitis were significantly associated with increased risk of all‐cause dementia and subtypes, with dose–effect relationships with the severity of allergic diseases. ANN NEUROL 2023;93:384–397
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