Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 479
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Small ; 20(12): e2308193, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37953460

RESUMEN

Designing catalysts to proceed with catalytic reactions along the desired reaction pathways, e.g., CO2 methanation, has received much attention but remains a huge challenge. This work reports one Ru1Ni single-atom alloy (SAA) catalyst (Ru1Ni/SiO2) prepared via a galvanic replacement reaction between RuCl3 and Ni nanoparticles (NPs) derived from the reduction of Ni phyllosilicate (Ni-ph). Ru1Ni/SiO2 achieved much improved selectivity toward hydrogenation of CO2 to CH4 and catalytic activity (Turnover frequency (TOF) value: 40.00 × 10-3 s-1), much higher than those of Ni/SiO2 (TOF value: 4.40 × 10-3 s-1) and most reported Ni-based catalysts (TOF value: 1.03 × 10-3-11.00 × 10-3 s-1). Experimental studies verify that Ru single atoms are anchored onto the Ni NPs surface via the Ru1-Ni coordination accompanied by electron transfer from Ru1 to Ni. Both in situ experiments and theoretical calculations confirm that the interface sites of Ru1Ni-SAA are the intrinsic active sites, which promote the direct dissociation of CO2 and lower the energy barrier for the hydrogenation of CO* intermediate, thereby directing and enhancing the CO2 hydrogenation to CH4.

2.
Small ; 20(12): e2307454, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37948430

RESUMEN

Lead halide hybrid perovskites have made great progress in direct X-ray detection and broadband photodetection, but the existence of toxic Pb and the demand for external operating voltage have severely limited their further applications and operational stability improvements. Therefore, exploring "green" lead-free hybrid perovskite that can both achieve X-ray detection and broadband photodetection without external voltage is of great importance, but remains severely challenging. Herein, using centrosymmetric (BZA)3BiI6 (1, BZA = benzylamine) as a template, a pair of chiral-polar lead-free perovskites, (BZA)2(R/S-PPA)BiI6 (2-R/S, R/S-PPA = (R/S)-1-Phenylpropylamine) are successfully obtained by introducing chiral aryl cations of (R/S)-1-Phenylpropylamine. Compared to 1, chiral-polar 2-R presents a significant irradiation-responsive bulk photovoltaic effect (BPVE) with an open circuit photovoltage of 0.4 V, which enables it with self-powered X-ray, UV-vis-NIR broadband photodetection. Specifically, 2-R device exhibits an ultralow detection limit of 18.5 nGy s-1 and excellent operational stability. Furthermore, 2-R as the first lead-free perovskite achieves significant broad-spectrum (377-940 nm) photodetection via light-induced pyroelectric effect. This work sheds light on the rational crystal reconstruction engineering and design of "green" hybrid perovskite toward high-demanded self-powered radiation detection and broadband photodetection.

3.
Small ; 20(23): e2310166, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38145326

RESUMEN

Polarization photodetection taking advantage of the anisotropy of 2D materials shines brilliantly in optoelectronic fields owing to differentiating optical information. However, the previously reported polarization detections are mostly dependent on external power sources, which is not conducive to device integration and energy conservation. Herein, a 2D polar perovskite (CBA)2CsPb2Br7 (CCPB, CBA = 4-chlorobenzyllamine) has been successfully synthesized, which shows anticipated bulk photovoltaic effect (BPVE) with an open-circuited photovoltage up to ≈0.2 V. Devices based on CCPB monomorph fulfill a fascinating self-powered polarized photodetection with a large polarization ratio of 2.7 at room temperature. Moreover, CCPB features a high phase-transition temperature (≈475 K) which prompts such self-powered polarized photodetection in a large temperature window of device operation, since BPVE generated by spontaneous polarization can only exist in the polar structure prior to the phase transition. Further computational investigation reveals the introduction of CBA+ with a large dipole moment contributes to quite large polarization (17.5 µC cm-2) and further super high phase transition temperature of CCPB. This study will promote the application of 2D perovskite materials for self-powered polarized photodetection in high-temperature conditions.

4.
Opt Lett ; 49(12): 3532-3535, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38875663

RESUMEN

In lensless imaging using a Fresnel zone aperture (FZA), it is generally believed that the resolution is limited by the outermost ring breadth of the FZA. The limitation has the potential to be broken according to the multi-order property of binary FZAs. In this Letter, we propose to use a high-order component of the FZA as the point spread function (PSF) to develop a high-order transfer function backpropagation (HBP) algorithm to enhance the resolution. The proportion of high-order diffraction energy is low, leading to severe defocus noise in the reconstructed image. To address this issue, we propose a Compound FZA (CFZA), which merges two partial FZAs operating at different orders as the mask to strike a balance between the noise and resolution. Experimental results verify that the CFZA-based camera has a resolution that is double that of a traditional FZA-based camera with an identical outer ring breadth and can be reconstructed with high quality by a single HBP without calibration. Our method offers a cost-effective solution for achieving high-resolution imaging, expanding the potential applications of FZA-based lensless imaging in a variety of areas.

5.
Int Microbiol ; 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38833100

RESUMEN

Salvia miltiorrhiza is a kind of medicinal plant with various pharmacological activities. Few studies on the composition and diversity of rhizosphere microbial communities at different growth stages have been conducted on Salvia miltiorrhiz; in particular, salviorrhiza grows in soil that has been continuously planted for 3 years. The purpose of this study was to understand the changes of soil physicochemical properties of Salvia miltiorrhiza at different growth stages, and to study the composition and diversity of rhizosphere microbial community at different growth stages. Illumina NovaSeq sequencing technology was used to analyze the bacterial 16S rRNA gene and the fungal ITS region in the rhizosphere soil of Salvia miltiorrhiza at different growth stages. The results showed that the dominant bacterial phyla in the Salvia miltiorrhiza rhizosphere were Proteobacteria, Bacteroidetes, Acidobacteria, Firmicutes, Actinobacteria, and Chloroflexi. The dominant fungal phyla were Ascomycota, Mortierellomycota, Basidiomycota, and Rozellomycota. During the growth of Salvia miltiorrhiza, the physical and chemical properties of soil changed. As the Salvia miltiorrhiza grew, the content of available phosphorus, available potassium, pH, nitrate nitrogen, and ammonium nitrogen significantly decreased. Ammonium nitrogen and nitrate nitrogen had a greater impact on the bacterial community structure in the rhizosphere than on the fungal community structure. The work was to reveal differences in the rhizosphere bacterial and fungal community structure during different growth stages of Salvia miltiorrhiza, further understand the changes of rhizosphere microbial ecological characteristics and soil physicochemical properties during the cultivation of Salvia miltiorrhiza.

6.
Inorg Chem ; 63(21): 9753-9762, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38743025

RESUMEN

Global warming and heavy metal pollution pose tremendous challenges to human development, and photocatalysis is considered to be an effective strategy to solve these problems. Herein, copper(II) tetra (4-carboxyphenyl) porphyrin (CuTCPP) molecules were successfully in situ loaded onto Bi4O5Br2 by a hydrothermal approach. A series of experimental results show that the light absorption capacity and photogenerated carrier separation efficiency were synchronously enhanced after the construction of CuTCPP/Bi4O5Br2 composites. Hence, the as-prepared composites possess significantly improved photocatalytic ability for both CO2 and Cr(VI) reduction. Specifically, CuTCPP/Bi4O5Br2-2 achieves a CO generation rate of 17.14 µmol g-1 under 5 h irradiation, which is twice as high as that of Bi4O5Br2 (8.57 µmol g-1). Besides, the optimized CuTCPP/Bi4O5Br2-2 also exhibits a removal rate of 61.87% for Cr(VI) within 100 min under irradiation. Furthermore, the mechanism of CO2 and Cr(VI) photoreduction was explored by in situ Fourier transform infrared spectroscopy and capture experiments, respectively. This work can be a reference toward the construction of photocatalysts with high activity for solar energy conversion.

7.
Nanotechnology ; 35(22)2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38387092

RESUMEN

Modification and functionalization of porous aromatic framework (PAF) materials have emerged as crucial research directions in various fields. In this study, we employed a hydrothermal method to synthesize a carbon quantum dots (CQDs) solution. By loading different amounts of CQDs onto the surface of PAF-45 material through ultrasonic and hydrothermal treatments, we successfully formed CQDs/PAF-45 composite materials. The introduction of CQDs effectively transformed the hydrophobic nature of PAF-45 into a hydrophilic material, thereby overcoming the challenge of achieving efficient contact between PAF catalysts and reactants in aqueous solutions. In the photocatalytic degradation experiments of Rhodamine B (RhB), tetracycline, CQDs/PAF-45 composite materials surpassed that of the pristine PAF-45 material. Notably, the 1 wt% CQDs/PAF-45 composite material exhibited the highest photocatalytic activity, with degradation efficiencies for Rhodamine B, tetracycline, and phenol approximately 1.4 times, 1.5 times and 1.5 times higher than those of the PAF-45 material, respectively.

8.
BMC Pregnancy Childbirth ; 24(1): 308, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38658867

RESUMEN

BACKGROUND: In cancer biology, circRAD18 promotes glucose metabolism, potentially indicating its involvement in glucose metabolism-related disorders, such as gestational diabetes mellitus (GDM). The present study investigated the predictive role of circRAD18 in GDM and its potential adverse effects. METHODS: A total of 482 women who intended to get pregnant in short-term were enrolled. For those who successfully conceived, plasma samples were collected and followed up until delivery to monitor the occurrence of GDM and its associated adverse events. The accumulation of circRAD18 in plasma was analyzed using RT-qPCR. GDM-free curves and ROC curves were plotted to assess the predictive value of plasma circRAD18 for GDM. RESULTS: After admitting 482 female patients, 388 of them achieved pregnancy within half a year. During the follow-up period, 52 cases were diagnosed with GDM. Compared to non-GDM group (n = 336), the GDM group (n = 52) had a lower accumulation level of circRAD18 on the day of pregnancy confirmation. In addition, low levels of circRAD18 accumulation on that day distinguished potential GDM patients from non-GDM cases. The 388 cases were divided into high and low circRAD18 level groups (n = 194). GDM-free curve analysis showed that patients in the low circRAD18 level group had a higher incidence of GDM compared to the high level group (43/194 vs. 9/194). A close association was found between low levels of plasma circRAD18 and hypertension, but not premature delivery, intrauterine death, malformation, intrauterine infection, miscarriage, macrosomia or intrauterine distress. CONCLUSION: The reduction in the accumulation of plasma circRAD18 is predictive of GDM and hypertension in pregnant women.


Asunto(s)
Diabetes Gestacional , Valor Predictivo de las Pruebas , ARN Circular , Humanos , Femenino , Diabetes Gestacional/sangre , Diabetes Gestacional/diagnóstico , Embarazo , Adulto , ARN Circular/sangre , Biomarcadores/sangre , Curva ROC
9.
Nano Lett ; 23(22): 10367-10373, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37939002

RESUMEN

The synthesis of highly dispersed Au nanoclusters that are stable under elevated temperatures in heterogeneous catalysis is challenging. Here, we directly observe a strong metal-support interaction (SMSI)-induced dispersion of Au nanoparticles (NPs) on α-MoC using an environmentally atomically resolved secondary imaging technique. Under a realistic environment, Au NPs flatten and spread out on the α-MoC to form two-dimensional atomic layered clusters. The formed highly dispersed Au/α-MoC catalyst shows excellent stability at 600 °C for 160 h in the reverse water-gas shift reaction. The X-ray photoelectron spectrum and extended X-ray absorption fine structure results show that Au NPs gradually become low-coordination-number cluster species and lose electrons to become Auδ+; these form chemical bonds with the α-MoC support and are responsible for the dispersion behavior. This work provides an insightful understanding of dispersion behavior and promotes the rational design and synthesis of reverse sintering catalysts.

10.
J Environ Manage ; 359: 121054, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38728982

RESUMEN

Semi-arid regions present unique challenges for maintaining aquatic biological integrity due to their complex evolutionary mechanisms. Uncovering the spatial patterns of aquatic biological integrity in these areas is a challenging research task, especially under the compound environmental stress. Our goal is to address this issue with a scientifically rigorous approach. This study aims to explore the spatial analysis and diagnosis method of aquatic biological based on the combination of machine learning and statistical analysis, so as to reveal the spatial differentiation patterns and causes of changes of aquatic biological integrity in semi-arid regions. To this end, we have introduced an innovative approach that combines XGBoost-SHAP and Fuzzy C-means clustering (FCM), we successfully identified and diagnosed the spatial variations of aquatic biological integrity in the Wei River Basin (WRB). The study reveals significant spatial variations in species number, diversity, and aquatic biological integrity of phytoplankton, serving as a testament to the multifaceted responses of biological communities under the intricate tapestry of environmental gradients. Delving into the depths of the XGBoost-SHAP algorithm, we discerned that Annual average Temperature (AT) stands as the pivotal driver steering the spatial divergence of the Phytoplankton Integrity Index (P-IBI), casting a positive influence on P-IBI when AT is below 11.8 °C. The intricate interactions between hydrological variables (VF and RW) and AT, as well as between water quality parameters (WT, NO3-N, TP, COD) and AT, collectively sculpt the spatial distribution of P-IBI. The fusion of XGBoost-SHAP with FCM unveils pronounced north-south gradient disparities in aquatic biological integrity across the watershed, segmenting the region into four distinct zones. This establishes scientific boundary conditions for the conservation strategies and management practices of aquatic ecosystems in the region, and its flexibility is applicable to the analysis of spatial heterogeneity in other complex environmental contexts.


Asunto(s)
Aprendizaje Automático , Fitoplancton , Ríos , Monitoreo del Ambiente/métodos , Algoritmos
11.
Molecules ; 29(6)2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38543048

RESUMEN

SYAUP-491 is a novel alkyl sulfonamide. In this study, in vivo and in vitro tests were performed along with a proteomic analysis to determine the effects and underlying mechanisms of the antibacterial activity of SYAUP-491 against the causative agent of bacterial leaf blight in rice. The antibacterial test results suggested that SYAUP-491 exhibited significant activities against Xanthomonas oryzae pv. oryzae (Xoo) in vitro and in vivo. The minimal EC50 values reached 6.96 µg/mL and the curative activity reached 74.1%. Detailed studies demonstrated that SYAUP-491 altered membrane permeability and caused morphological changes. Based on proteomics results, SYAUP-491 might inhibit bacterial protein synthesis. SYAUP-491 may disrupt and alter cell membrane permeability and could further act on ribosomes in the bacterial body. Given the above results, SYAUP-491 could serve as a new lead compound in the research of antibacterial control of plant pathogenic bacterial disease.


Asunto(s)
Oryza , Xanthomonas , Proteómica , Antibacterianos/farmacología , Sulfonamidas , Oryza/microbiología , Enfermedades de las Plantas/prevención & control , Enfermedades de las Plantas/microbiología , Pruebas de Sensibilidad Microbiana
12.
J Community Health Nurs ; : 1-8, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39150016

RESUMEN

PURPOSE: To assess the impact of incorporating internet-based resources and popular science workshops on self-care management among hemodialysis patients with arteriovenous fistula. DESIGN: A randomized controlled trial involving 110 hemodialysis patients with arteriovenous fistula, randomly assigned to either the experimental or control group. METHODS: The experimental group received self-management training utilizing internet resources and interactive workshops, while the control group received conventional health education methods. After the intervention, the self-management proficiency of both groups was assessed, including comprehension of arteriovenous fistula-related information, satisfaction levels, self-care abilities, engagement in functional exercises, quality of life, and other relevant factors. FINDINGS: Patients in the experimental group exhibited significantly greater proficiency in arteriovenous fistula self-management knowledge, higher levels of patient satisfaction, enhanced self-management abilities, improved functional exercise performance, and better overall quality of life compared to those in the control group (p < 0.05). CONCLUSIONS: The combination of internet resources and popular science workshops presents a novel and promising approach for educating and promoting self-care management among hemodialysis patients with arteriovenous fistula. This method holds potential for widespread dissemination and implementation in science education. CLINICAL EVIDENCE: The study demonstrates the tangible benefits of integrating internet-based resources and popular science workshops into self-management training for arteriovenous fistula among hemodialysis patients, as evidenced by improved knowledge, satisfaction, abilities, exercise performance, and quality of life in the experimental group compared to the control group.

13.
BMC Oral Health ; 24(1): 1194, 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39379876

RESUMEN

BACKGROUND: Issues associated with proton pump inhibitor (PPI) usage have been documented. PPIs affect the gastrointestinal microbiome, as well as the saliva microbiota of healthy individuals. However, the alterations in the saliva microbiota of laryngopharyngeal reflux (LPR) patients remain unclear. This study aims to examine the composition of saliva microbiota in LPR patients before and after PPI usage through a self-controlled study. METHODS: Thirty-two adult LPR patients participated in the study. Saliva samples were collected before and after an 8-week regimen of twice-daily administration of 20-mg esomeprazole. The impact of PPI administration on bacterial communities was assessed using 16 S rRNA gene sequencing. The functional and metabolic changes in saliva microbial communities after PPI usage were analyzed using PICRUSt2 based on our 16 S rRNA gene sequencing results. RESULTS: The alpha diversity within the salivary microbiota, as measured by the PD-whole-tree index, exhibited a significant difference between samples collected before and after PPI application (P = 0.038). Additionally, PCoA analysis of unweighted UniFrac distances (beta diversity) revealed distinct separation of saliva sample microbiota structures before and after PPI application in LPR patients, with statistical significance (Adonis test, R2 = 0.063, P< 0.010). Taxon-based analysis indicated that PPI administration increased the abundance of Epsilonproteobacteria, Campylobacterales, Campylobacteraceae, Campylobacter, and Campylobacter_gracilis, while reducing the abundance of Lactobacillaceae and Lactobacillus in salivary samples ( P< 0.050). Using LEfSe to compare bacterial abundances, Bacillaceae and Anoxybacillus were found to be enriched before PPI usage in LPR patients. Furthermore, the proportion of genes responsible for indole alkaloid biosynthesis in the salivary microbiota of LPR patients significantly increased after PPI therapy (P< 0.050). CONCLUSIONS: These findings indicate that PPIs induce alterations in the salivary microbiota of LPR patients. CHINESE CLINICAL TRIAL REGISTRY: No. ChiCTR2300067507. Registered on January 10,2023 retrospectively.


Asunto(s)
Reflujo Laringofaríngeo , Microbiota , Inhibidores de la Bomba de Protones , Saliva , Humanos , Saliva/microbiología , Inhibidores de la Bomba de Protones/uso terapéutico , Masculino , Femenino , Reflujo Laringofaríngeo/microbiología , Reflujo Laringofaríngeo/tratamiento farmacológico , Microbiota/efectos de los fármacos , Persona de Mediana Edad , Adulto , Esomeprazol/uso terapéutico , ARN Ribosómico 16S/análisis , Anciano
14.
Angew Chem Int Ed Engl ; : e202412062, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39315608

RESUMEN

Developing a new route to produce aromatic amines as key chemicals from renewable phenols is a benign alternative to current fossil-based routes like nitroaromatic hydrogenation, but is challenging because of the high dissociation energy of the Ar-OH bond and difficulty in controlling side reactions. Herein, an aerosolizing-pyrolysis strategy was developed to prepare high-density single-site cationic Pd species immobilized on CeO2 (Pd1/CeO2) with excellent sintering resistance. The obtained Pd1/CeO2 catalysts achieved remarkable selectivity of important aromatic amines (yield up to 76.2%) in the phenols amination with amines without external hydrogen sources, while Pd nano-catalysts mainly afforded phenyl-ring-saturation products. The excellent catalytic properties of the Pd1/CeO2 are closely related to high-loading Pd single-site catalysts with abundant surface defect sites and suitable acid-base properties. This report provides a sustainable route for producing aromatic amines from renewable feedstocks.

15.
Angew Chem Int Ed Engl ; 63(21): e202402176, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38470010

RESUMEN

Electrosynthesis coupled hydrogen production (ESHP) mostly involves catalyst reconstruction in aqueous phase, but accurately identifying and controlling the process is still a challenge. Herein, we modulated the electronic structure and exposed unsaturated sites of metal-organic frameworks (MOFs) via ligand defect to promote the reconstruction of catalyst for azo electrosynthesis (ESA) coupled with hydrogen production overall reaction. The monolayer Ni-MOFs achieved 89.8 % Faraday efficiency and 90.8 % selectivity for the electrooxidation of 1-methyl-1H-pyrazol-3-amine (Pyr-NH2) to azo, and an 18.5-fold increase in H2 production compared to overall water splitting. Operando X-ray absorption fine spectroscopy (XAFS) and various in situ spectroscopy confirm that the ligand defect promotes the potential dependent dynamic reconstruction of Ni(OH)2 and NiOOH, and the reabsorption of ligand significantly lowers the energy barrier of rate-determining step (*Pyr-NH to *Pyr-N). This work provides theoretical guidance for modulation of electrocatalyst reconstruction to achieve highly selective ESHP.

16.
Angew Chem Int Ed Engl ; 63(27): e202320014, 2024 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-38598078

RESUMEN

Amino acids are the building blocks of proteins and are widely used as important ingredients for other nitrogen-containing molecules. Here, we report the sustainable production of amino acids from biomass-derived hydroxy acids with high activity under visible-light irradiation and mild conditions, using atomic ruthenium-promoted cadmium sulfide (Ru1/CdS). On a metal basis, the optimized Ru1/CdS exhibits a maximal alanine formation rate of 26.0 molAla ⋅ gRu -1 ⋅ h-1, which is 1.7 times and more than two orders of magnitude higher than that of its nanoparticle counterpart and the conventional thermocatalytic process, respectively. Integrated spectroscopic analysis and density functional theory calculations attribute the high performance of Ru1/CdS to the facilitated charge separation and O-H bond dissociation of the α-hydroxy group, here of lactic acid. The operando nuclear magnetic resonance further infers a unique "double activation" mechanism of both the CH-OH and CH3-CH-OH structures in lactic acid, which significantly accelerates its photocatalytic amination toward alanine.


Asunto(s)
Aminoácidos , Biomasa , Compuestos de Cadmio , Rutenio , Sulfuros , Sulfuros/química , Rutenio/química , Compuestos de Cadmio/química , Catálisis , Aminoácidos/química , Procesos Fotoquímicos , Teoría Funcional de la Densidad , Luz
17.
Angew Chem Int Ed Engl ; 63(43): e202410979, 2024 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-38967363

RESUMEN

Catalytic removal of alkynes is essential in industry for producing polymer-grade alkenes from steam cracking processes. Non-noble Ni-based catalysts hold promise as effective alternatives to industrial Pd-based catalysts but suffer from low activity. Here we report embedding of single-atom Pd onto the NiGa intermetallic surface with replacing Ga atoms via a well-defined synthesis strategy to design Pd1-NiGa catalyst for alkyne semi-hydrogenation. The fabricated Pd1Ni2Ga1 ensemble sites deliver remarkably higher specific mass activity under superb alkene selectivity of >96 % than the state-of-the-art catalysts under industry-relevant conditions. Integrated experimental and computational studies reveal that the single-atom Pd synergizes with the neighbouring Ni sites to facilitate the σ-adsorption of alkyne and dissociation of hydrogen while suppress the alkene adsorption. Such synergistic effects confer the single-atom Pd on the NiGa intermetallic with a Midas touch for alkyne semi-hydrogenation, providing an effective strategy for stimulating low active Ni-based catalysts for other selective hydrogenations in industry.

18.
J Am Chem Soc ; 145(3): 1524-1529, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36629502

RESUMEN

Benefiting from superior semiconducting properties and the angle-dependence of the bulk photovoltaic effect (BPVE) on polarized light, the two-dimensional (2D) hybrid perovskite ferroelectrics are developed for sensitive self-powered polarized photodetection. Most of the currently reported ferroelectric-driven polarized photodetection is restricted to the shortwave optical response, and expanding the response range is urgently needed. Here we report the first instance of a FAPbI3-derived (2D) perovskite ferroelectric, (BA)2(FA)Pb2I7 (1, BA is n-butylammonium, FA is formamidinium). It exhibited a notably high thermostability and broad-spectrum adsorption extending to around 650 nm. Significantly, 1 demonstrated ferroelectricity-driven self-powered polarized photodetection under 637 nm with an anisotropic photocurrent ratio of ∼1.96, ultrahigh detectivity of 3.34 × 1012 Jones, and long-term repetition. This research will shed light on the development of new ferroelectrics for potential application in broad-spectrum polarization-based optoelectronics.

19.
J Am Chem Soc ; 145(23): 12853-12860, 2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37263965

RESUMEN

Chemiresistive sensing has been regarded as the key monitoring technique, while classic oxide gas detection devices always need an external power supply. In contrast, the bulk photovoltage of photoferroelectric materials could provide a controllable power source, holding a bright future in self-powered gas sensing. Herein, we present a new photoferroelectric ([n-pentylaminium]2[ethylammonium]2Pb3I10, 1), which possesses large spontaneous polarization (∼4.8 µC/cm2) and prominent visible-photoactive behaviors. Emphatically, driven by the bulk photovoltaic effect, 1 enables excellent self-powered sensing responses for NO2 at room temperature, including extremely fast response/recovery speeds (0.15/0.16 min) and high sensitivity (0.03 ppm-1). Such figures of merit are superior to those of typical inorganic systems (e.g., ZnO) using an external power supply. Theoretical calculations and in situ diffuse reflectance infrared Fourier transform spectroscopy measurements confirm the great selectivity of 1 for NO2. As far as we know, this is the first realization of ferroelectricity-driven self-powered gas detection. Our work sheds light on the self-powered sensing systems and provides a promising way to broaden the functionalities of photoferroelectrics.

20.
J Am Chem Soc ; 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37792912

RESUMEN

Dry reforming of methane (DRM) has been investigated for more than a century; the paramount stumbling block in its industrial application is the inevitable sintering of catalysts and excessive carbon emissions at high temperatures. However, the low-temperature DRM process still suffered from poor reactivity and severe catalyst deactivation from coking. Herein, we proposed a concept that highly durable DRM could be achieved at low temperatures via fabricating the active site integration with light irradiation. The active sites with Ni-O coordination (NiSA/CeO2) and Ni-Ni coordination (NiNP/CeO2) on CeO2, respectively, were successfully constructed to obtain two targeted reaction paths that produced the key intermediate (CH3O*) for anticoking during DRM. In particular, the operando diffuse reflectance infrared Fourier transform spectroscopy coupling with steady-state isotopic transient kinetic analysis (operando DRIFTS-SSITKA) was utilized and successfully tracked the anticoking paths during the DRM process. It was found that the path from CH3* to CH3O* over NiSA/CeO2 was the key path for anticoking. Furthermore, the targeted reaction path from CH3* to CH3O* was reinforced by light irradiation during the DRM process. Hence, the NiSA/CeO2 catalyst exhibits excellent stability with negligible carbon deposition for 230 h under thermo-photo catalytic DRM at a low temperature of 472 °C, while NiNP/CeO2 shows apparent coke deposition behavior after 0.5 h in solely thermal-driven DRM. The findings are vital as they provide critical insights into the simultaneous achievement of low-temperature and anticoking DRM process through distinguishing and directionally regulating the key intermediate species.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA