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1.
Angew Chem Int Ed Engl ; : e202409876, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38923765

ABSTRACT

Lattice-oxygen activation has emerged as a popular strategy for optimizing the performance and selectivity of oxide-based thermocatalysis and electrolysis. However, the significance of lattice oxygen in oxide photocatalysts has been ignored, particularly in gas‒solid reactions. Here, using methane oxidation over a Ru1@ZnO single-atom photocatalyst as the prototypical reaction and via 18O isotope labelling techniques, we found that lattice oxygen can directly participate in gas‒solid reactions. Lattice oxygen played a dominant role in the photocatalytic reaction, as determined by estimating the kinetic constants in the initial stage. Furthermore, we discovered that dynamic diffusion between O2 and lattice oxygen proceeded even in the absence of targeted reactants. Finally, single-atom Ru can facilitate the activation of adsorbed O2 and the subsequent regeneration of consumed lattice oxygen, thus ensuring high catalyst activity and stability. The results provide guidance for next-generation oxide photocatalysts with improved activities and selectivities.

2.
Curr Med Chem ; 2024 May 02.
Article in English | MEDLINE | ID: mdl-38698750

ABSTRACT

BACKGROUND: The immune system is linked to the prognosis and response to treatment of patients with cancer. However, the clinical implication of peripheral blood immune cells in cholangiocarcinoma (CCA) remains vague. Thus, we aimed to assess whether peripheral circulating immune cells could be used as an indicator for prognosis and chemotherapeutic efficacy in CCA. METHODS: The distributions of immune subsets were analyzed in peripheral blood samples from 141 patients with CCA and 131 healthy volunteers by using flow cytometry. The variation in the subset distribution in the two groups and the relationship between clinicopathological features and the subpopulations were investigated. Meanwhile, we assessed the implications of lymphocyte subsets as predictors of chemotherapy outcomes and overall survival (OS). RESULTS: The proportion of total lymphocytes decreased, while the percentages of activated T cells as well as CD4+CD25+ regulatory T cells (Tregs) increased in CCA. Notably, lymphocyte proportion decreased in patients with regional lymph node (N) (p=0.016) and distant metastasis (M) (p= 0.001). Furthermore, our study showed that peripheral blood lymphocyte subsets were significantly correlated with chemotherapy efficacy, with increased proportions of CD3+ cells (p=0.021) and CD4+ cells (p=0.016) in the effective group. Finally, the Kaplan-Meier analysis indicated that patients with high natural killer (NK) cell proportion might have prolonged OS (p = 0.028). CONCLUSION: The relationship between circulating immune cells with prognosis and chemotherapy response in patients with CCA highlights their potential application as an indicator of CCA prognosis and stratification of chemotherapy response.

3.
Article in English | MEDLINE | ID: mdl-38758499

ABSTRACT

Plant-derived exosome-like nanoparticles (PELNs) are natural nanocarriers and effective delivery systems for plant microRNAs (miRNAs). These PELN-carrying plant miRNAs can regulate mammalian genes across species, thereby increasing the diversity of miRNAs in mammals and exerting multi-target effects that play a crucial role in diseases, particularly cancer. PELNs demonstrate exceptional stability, biocompatibility, and targeting capabilities that protect and facilitate the up-take and cross-kingdom communication of plant miRNAs in mammals. Primarily ingested and absorbed within the gastrointestinal tract of mammals, PELNs preferentially act on the intestine to regulate intestinal homeostasis through functional miRNA activity. The oncogenesis and progression of cancer are closely associated with disruptions in intestinal barriers, ecological imbalances, as well as secondary changes, such as abnormal inflammatory reactions caused by them. Therefore, it is imperative to investigate whether PELNs exert their anticancer effects by regulating mammalian intestinal homeostasis and inflammation. This review aims to elucidate the intrinsic crosstalk relationships and mechanisms of PELNs-mediated miRNAs in maintaining intestinal homeostasis, regulating inflammation and cancer treatment. Furthermore, serving as exceptional drug delivery systems for miRNAs molecules, PELNs offer broad prospects for future applications, including new drug research and development along with drug carrier selection within targeted drug delivery approaches for cancer therapy.

4.
J Colloid Interface Sci ; 668: 502-511, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38691960

ABSTRACT

The demand for clean energy sources has driven focus towards advanced electrochemical systems. However, the sluggish kinetics of the oxygen evolution reaction (OER) constrain the energy conversion efficiency of relevant devices. Herein, a one-step method is reported to grow oxygen vacancies (Vo) rich NiFeAg layered double hydroxides nanoclusters on carbon cloth (Vo-NiFeAg-LDH/CC) for serving as the self-supporting electrode to catalyze OER. The OER performance of Vo-NiFeAg-LDH/CC has been remarkably enhanced through Ag and Vo co-modification compared with pristine NiFe-LDH, achieving a low Tafel slope of 49.7 mV dec-1 in 1 m KOH solution. Additionally, the current density of Vo-NiFeAg-LDH/CC is 3.23 times higher than that of the state-of-art IrO2 at 2 V under an alkaline flow electrolyzer setup. Theoretical calculations and experimental results collectively demonstrate that Ag dopant and Vo strengthen the O* adsorption with active sites, further promoting the deprotonation step from OH* to O* and accelerating the catalytic reaction. In a word, this work clarifies the structural correlation and synergistic mechanism of Ag dopant and Vo, providing valuable insights for the rational design of catalyst for renewable energy applications.

5.
Adv Clin Exp Med ; 2024 04 29.
Article in English | MEDLINE | ID: mdl-38683045

ABSTRACT

BACKGROUND: Gecko has been widely documented in Chinese scientific literature as an anti-tumor agent for various illnesses for thousands of years, and more recently, it has been examined for its anti-tumor effects on several cancers. The effect of Gecko microRNAs (miRNAs) on hepatocellular carcinoma (HCC) has not yet been reported. OBJECTIVES: This study was designed to identify miRNAs in Gecko through small RNA sequencing and utilize bioinformatics techniques to construct a potential regulatory network and explore the possible mechanisms of exogenous miRNAs involved in HCC. MATERIAL AND METHODS: RNA was extracted from Gecko tablets, and we screened the Gecko miRNA expression dataset after high-throughput sequencing. Bioinformatics analysis was used to identify novel Gecko and HCC survival-related miRNA-mRNA cross-species regulation networks. RESULTS: miR-100-5p, miR-99a-5p and miR-101-3p were identified as critical for the role of Geckos in HCC. Nine downstream mRNAs (EZH2, KPNA2, LMNB1, LRRC1, MRGBP, SMARCD1, STMN1, SUB1, and UBE2A) were identified as target genes for critical miRNAs. A miRNA-mRNA regulatory network was constructed, and Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed these key mRNAs might be associated with both the suppression and progression of HCC. The novel network significantly correlated with the abundance of multiple immune cells, as determined with immune infiltration analysis. CONCLUSIONS: These findings suggest that Gecko may inhibit progression and exert a therapeutic effect on HCC by targeting critical miRNA-mRNA networks for cross-species regulation. It also provides a reference for future research and development of traditional Chinese medicine (TCM).

6.
Nat Commun ; 15(1): 2023, 2024 Mar 06.
Article in English | MEDLINE | ID: mdl-38448472

ABSTRACT

Propelled by the structure of water oxidation co-catalysts in natural photosynthesis, molecular co-catalysts have long been believed to possess the developable potential in artificial photosynthesis. However, the interfacial complexity between light absorber and molecular co-catalyst limits its structural stability and charge transfer efficiency. To overcome the challenge, a supramolecular scaffold with the [FeCl4] catalytic units is reported, which undergo a water-nucleophilic attack of the water oxidation reaction, while the supramolecular matrix can be in-situ grown on the surface of photoelectrode through a simple chemical polymerization to be a strongly coupled interface. A well-defined BiVO4 photoanode hybridized with [FeCl4] units in polythiophene reaches 4.72 mA cm-2 at 1.23 VRHE, which also exhibits great stability for photoelectrochemical seawater splitting due to the restraint on chlorine evolution reaction by [FeCl4] units and polythiophene. This work provides a novel solution to the challenge of the interface charge transfer of molecular co-catalyst hybridized photoelectrode.

8.
Pathol Res Pract ; 253: 154985, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38039742

ABSTRACT

The expression of long non-coding RNAs (LncRNAs) in peripheral blood mononuclear cell (PBMC) and its clinical relevance in colorectal cancer (CRC) remains largely uncharacterized. To address these gaps, we investigated the expression profiles of lncRNAs in PBMC from CRC and healthy controls (HC) by RNA sequencing. The expression level of differentially expressed lncRNAs (DElncRNAs) were evaluated by quantitative PCR in PBMC samples from CRC patients and HC. A total of 447 DElncRNAs were identified, with 178 elevated lncRNAs and 269 decreased lncRNAs in PBMC from CRC patients as compared with that from HC. RT-PCR results supported a significant elevation of NEAT1:11, lnc-PDZD8-1:5 and LINC00910:16 in 98 CRC patients and 82 HC. The clinical implication of NEAT1:11, lnc-PDZD8-1:5 and LINC00910:16 as CRC diagnostic biomarker were determined by receiver operating characteristic (ROC) curve, showing sensitivity 74.5% and specificity 84.5% for joint detection the three lncRNAs. Notably, NEAT1:11 was closely related with the size and extent of primary tumor, with higher relative expression of NEAT1:11 in higher T stage (P = 0.0047). Moreover, NEAT1:11 was related with grade (P = 0.012). Collectively, PBMC from patients with CRC show significantly variable expression profiles of lncRNAs, and detection of these differential expression lncRNAs may provide useful information for basic and clinical research.


Subject(s)
Colorectal Neoplasms , RNA, Long Noncoding , Humans , RNA, Long Noncoding/metabolism , Leukocytes, Mononuclear/metabolism , Colorectal Neoplasms/diagnosis , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Gene Expression Regulation, Neoplastic/genetics , Biomarkers/metabolism , Biomarkers, Tumor/metabolism , Adaptor Proteins, Signal Transducing/metabolism
9.
Nat Mater ; 23(3): 383-390, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38062169

ABSTRACT

Transparent conducting oxides are a critical component in modern (opto)electronic devices and solar energy conversion systems, and forming textured functional films on them is highly desirable for property manipulation and performance optimization. However, technologically important materials show varied crystal structures, making it difficult to establish coherent interfaces and consequently the oriented growth of these materials on transparent conducting oxides. Here, taking lattice-mismatched hexagonal α-Fe2O3 and tetragonal fluorine-doped tin oxide as the example, atomic-level investigations reveal that a coherent ordered structure forms at their interface, and via an oxygen-mediated dimensional and chemical-matching manner, that is, matched Voronoi cells of oxygen sublattices, [110]-oriented α-Fe2O3 films develop on fluorine-doped tin oxide. Further measurements of charge transport characteristics and photoelectronic effects highlight the importance and advantages of coherent interfaces and well-defined orientation in textured α-Fe2O3 films. Textured growth of lattice-mismatched oxides, including spinel Co3O4, fluorite CeO2, perovskite BiFeO3 and even halide perovskite Cs2AgBiBr6, on fluorine-doped tin oxide is also achieved, offering new opportunities to develop high-performance transparent-conducting-oxide-supported devices.

10.
Ophthalmology ; 131(5): 589-594, 2024 May.
Article in English | MEDLINE | ID: mdl-38081329

ABSTRACT

PURPOSE: Aplasia of lacrimal and salivary glands (ALSG) is a syndromic disorder characterized by aplasia of lacrimal and salivary systems. Reported ophthalmic manifestations of ALSG include aplasia of lacrimal glands, punctal agenesis, lacrimal sac mucocele, and membranous congenital nasolacrimal duct obstruction (CNLDO). Bony CNLDO, a rare clinical entity, has not been associated with any syndromic disorder. This study investigated the relationship between genetic mutations and bony CNLDO in 3 Chinese families with ALSG. DESIGN: Single-center observational case study. PARTICIPANTS: Three Chinese families with bony CNLDO, including 7 affected and 9 healthy family members. METHODS: Slit-lamp ophthalmic examination, comprehensive physical examination, orbital computed tomography (CT) imaging, cervicofacial magnetic resonance imaging, audiometry, and whole exome sequencing on periphery blood were performed. Variants were cross-referenced with 1000 control genomes and various population databases. Pathologic variants were identified using bioinformatic tools. MAIN OUTCOME MEASURES: Clinical examination, diagnostic imaging, whole exome sequencing, and bioinformatic analysis findings. RESULTS: Affected patients showed decreased tear production on the Schimer I test and reduced tear breakup time. Bony CNLDO was observed on CT, showing unilateral or bilateral bony termination at the middle or terminal segment of the nasolacrimal canal. Magnetic resonance imaging showed aplasia or absence of lacrimal, parotid, and submandibular glands. Physical examination revealed normal ears, digits, and facial morphology. Audiometry and dental assessment were conducted on the pediatric patients and yielded normal results. The clinical characteristics of patients aligned with a diagnosis of ALSG. Genomic analysis revealed 3 novel heterozygous missense mutations of the Fgf10 gene: c.316T→C, c.327C→G, and c.332T→G. The inheritance pattern was autosomal dominant with variable penetrance. These variants were not observed in 1000 control genomes and population databases. These variant positions also were shown to be highly conserved across various animal species. Mutated genes and proteins were predicted as deleterious with most computational models, with a few suggesting they may be benign. CONCLUSIONS: Bony CNLDO was identified as a novel phenotype of ALSG implicated by missense mutations of highly conserved residues in the Fgf10 gene. These cases broadened our knowledge of Fgf10-related phenotypes and prompted clinicians to consider syndromic associations in patients with bony CNLDO. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

11.
J Orthop Surg Res ; 18(1): 519, 2023 Jul 22.
Article in English | MEDLINE | ID: mdl-37480093

ABSTRACT

BACKGROUND: We compared the clinical efficacy of mini-open reduction and autologous bone grafting (GM) and closed reduction (GC) using intramedullary nailing for the treatment of tibial shaft fractures. METHODS: This retrospective study included 70 tibial shaft fractures treated with GM or GC between January 2018 and December 2021. The demographic characteristics and clinical outcomes were compared between the two treatment methods. RESULTS: This study included 70 patients who were followed-up for 12.4 months. In total, 31 and 39 patients were treated with GM and GC, respectively. The operative duration was significantly shorter for GM (95.2 ± 19.3 min) than for GC (105.5 ± 22.2 min, p = 0.0454). The number of radiation times was significantly lower for GM (14.7 ± 6.3) than for GC (22.2 ± 9.2, p < 0.005). There were no statistically significant differences between the groups in terms of the wound complication or infection rates. The malunion and nonunion rates were high after GC than after GM, but there are no significant differences between the groups. CONCLUSIONS: Closed reduction and intramedullary nailing remains the first choice for tibial shaft fractures. GM is a safe and effective treatment worth considering. Future prospective randomized controlled trials are warranted.


Subject(s)
Plastic Surgery Procedures , Tibial Fractures , Humans , Retrospective Studies , Bone Transplantation , Tibial Fractures/surgery , Open Fracture Reduction
12.
Nat Commun ; 14(1): 4266, 2023 Jul 17.
Article in English | MEDLINE | ID: mdl-37460538

ABSTRACT

Durability is one prerequisite for material application. Photoelectrochemical decomposition of seawater is a promising approach to produce clean hydrogen by using solar energy, but it always faces the problem of serious Cl- corrosion. We find that the main deactivation mechanism of the photoanode is oxide surface reconstruction accompanied by the coordination of Cl- during seawater splitting, and the stability of the photoanode can be effectively improved by enhancing the metal-oxygen interaction. Taking the metastable ß-Fe2O3 photoanode as an example, Sn added to the lattice can enhance the M-O bonding energy and hinder the transfer of protons to lattice oxygen, thereby inhibiting excessive surface hydration and Cl- coordination. Therefore, the bare Sn/ß-Fe2O3 photoanode delivers a record durability for photoelectrochemical seawater splitting over 3000 h.

13.
J Am Chem Soc ; 145(13): 7181-7189, 2023 Apr 05.
Article in English | MEDLINE | ID: mdl-36959719

ABSTRACT

Light-driven primary amine oxidation to imines integrated with H2 production presents a promising means to simultaneous production of high-value-added fine chemicals and clean fuels. Yet, the effectiveness of this strategy is generally limited by the poor charge separation of photocatalysts and uncontrolled hydrogenation of imines to secondary amines. Herein, a spatial decoupling strategy is proposed to isolate redox chemistry at distinct sites of photocatalysts, and CoP core-ZnIn2S4 shell (CoP@ZnIn2S4) coaxial nanorods are assembled as the proof-of-concept photocatalyst. Directional and ultrafast carrier separation occurs between the CoP core and the ZnIn2S4 shell, as confirmed by in situ X-ray photoelectron spectroscopy, surface photovoltage spectroscopy, and transient absorption spectroscopy analyses. Toward the photoconversion of model substrate benzylamine to N-benzylbenzaldimine, CoP@ZnIn2S4 exhibits a 48-time higher production rate and >99% selectivity when compared to ZnIn2S4 (ca. 20% selectivity), and the detailed reaction mechanism has been verified by in situ diffuse reflectance infrared Fourier transform spectroscopy.

14.
Nat Commun ; 14(1): 1013, 2023 Feb 23.
Article in English | MEDLINE | ID: mdl-36823177

ABSTRACT

The sustainable production of chemicals and fuels from abundant solar energy and renewable carbon sources provides a promising route to reduce climate-changing CO2 emissions and our dependence on fossil resources. Here, we demonstrate solar-powered formate production from readily available biomass wastes and CO2 feedstocks via photoelectrochemistry. Non-precious NiOOH/α-Fe2O3 and Bi/GaN/Si wafer were used as photoanode and photocathode, respectively. Concurrent photoanodic biomass oxidation and photocathodic CO2 reduction towards formate with high Faradaic efficiencies over 85% were achieved at both photoelectrodes. The integrated biomass-CO2 photoelectrolysis system reduces the cell voltage by 32% due to the thermodynamically favorable biomass oxidation over conventional water oxidation. Moreover, we show solar-driven formate production with a record-high yield of 23.3 µmol cm-2 h-1 as well as high robustness using the hybrid photoelectrode system. The present work opens opportunities for sustainable chemical and fuel production using abundant and renewable resources on earth-sunlight, biomass and CO2.

15.
Phys Chem Chem Phys ; 25(5): 3695-3701, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36651804

ABSTRACT

The effects of halogen (F, Cl, Br, I, and At) doping in the direct-band-gap ß-Fe2O3 semiconductor on its band structures and electron-hole recombination have been investigated by density functional theory. Doping Br, I, and At in ß-Fe2O3 leads to transformation from a direct-band-gap semiconductor to an indirect-band-gap semiconductor because their atomic radii are too large; however, F- and Cl-doped ß-Fe2O3 remain as direct-band-gap semiconductors. Due to the deep impurity states of the F dopant, this study focuses on the effects of the Cl dopant on the band structures of ß-Fe2O3. Two impurity levels are introduced when Cl is doped into ß-Fe2O3, which narrows the band gap by approximately 0.3 eV. After doping Cl, the light-absorption edge of ß-Fe2O3 redshifts from 650 to 776 nm, indicating that its theoretical solar to hydrogen efficiency for solar water splitting increases from 20.6% to 31.4%. In addition, the effective mass of the holes in halogen-doped ß-Fe2O3 becomes significantly larger than that in undoped ß-Fe2O3, which may suppress electron-hole recombination.

17.
Sci Bull (Beijing) ; 67(14): 1458-1466, 2022 Jul 30.
Article in English | MEDLINE | ID: mdl-36546189

ABSTRACT

Large-scale single crystals have potential applications in many fields, such as in ferroelectric and photoelectric energy conversion devices. Perovskite oxynitrides have also attracted attention in photoelectrochemical water splitting systems because of their high theoretical solar-to-hydrogen efficiencies. Nevertheless, the synthesis of perovskite oxynitride single crystals requires the coupling of cation exchange and ammonization processes, which is exceptionally challenging. The present study demonstrates an inorganic vapor method that provides, for the first time ever, high-quality epitaxial perovskite SrTaO2N single crystals on the centimeter scale. Assessments using Raman spectroscopy, crystal structure analysis and density functional theory determined that the conversion mechanism followed a topotactic transition mode. Compared with conventional SrTaO2N particle-assembled films, the SrTaO2N single crystals made in this work were free of interparticle interfaces and grain boundaries, which exhibited extremely high performance during photoelectrochemical water oxidation. In particular, these SrTaO2N single crystals showed the highest photocurrent density at 0.6 V vs. RHE (1.20 mA cm-2) and the highest photocurrent filling factor (47.6%) reported to date, together with a low onset potential (0.35 V vs. RHE). This onset potential was 200 mV less than that of the reported in situ SrTaO2N film, and the photocurrent fill factor was improved by 2 to 3 times.

18.
Int Immunopharmacol ; 111: 109157, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35988520

ABSTRACT

Pancreatic cancer is characterized by immune tolerance and immunotherapeutic resistance. Circulating cells may reflect the general immune status of the patient. However, the circulating immune status of pancreatic cancer are largely uncharacterized. Here, the subset distribution was analyzed in peripheral blood samples from 101 patients with pancreatic cancer and 142 healthy volunteers by using flow cytometry. The differences of the subpopulation distribution in the two groups and the relation between clinical parameters with the subset were determined. Moreover, the clinical application of each subset as prognosis biomarker was also assessed by Kaplan-Meier analysis. The reduced proportion of total lymphocyte and upregulated CD4/CD8 ratio were observed in pancreatic cancer than those in healthy controls. Of note, increased proportions of lymphocyte and NKT cells were noticed more frequently in patients over 60 years (P = 0.043) and patients with metastasis (P = 0.027), respectively. However, our correlation analyses revealed no correlation between the proportions of T cells, B cell and NK cells with clinicopathologic features. Furthermore, the analysis displayed that proportions of CD4+T cell, B cell and CD4/CD8 ratio significantly reduced in the cohort of post-operation, while the frequency of CD8+T cell and NKT cells elevated remarkably. Finally, the Kaplan-Meier analysis indicated that patients with high lymphocyte proportion might have prolonged overall survival (P = 0.007). The altered distribution of peripheral blood immune cell subpopulation in pancreatic cancer and its relationship with clinical outcome highlight the potential use of circulating immune subsets as prognostic biomarkers in pancreatic cancer.


Subject(s)
Pancreatic Neoplasms , Humans , Killer Cells, Natural , Lymphocyte Count , Pancreatic Neoplasms/pathology , Prognosis , Pancreatic Neoplasms
19.
Dalton Trans ; 51(33): 12494-12501, 2022 Aug 23.
Article in English | MEDLINE | ID: mdl-35916624

ABSTRACT

The development of stable, Earth-abundant, and high-activity molecular water oxidation catalysts under acidic and neutral conditions remains a great challenge. Here, the use of N-heterocyclic carbene (NHC)-based iron(III) complex 1 {[phenyl(tris(3-methylimidazol-1-ylidene))borate]2Fe(III)}+ as a catalyst for water oxidation under acidic and neutral conditions was investigated. Two iron(II) carbene complexes, 2 {[2,6-bis(3-methylimidazolium-1-yl)pyridine]2Fe}2+ and 3 {[2,6-bis(3-methylimidazolium-1-yl)pyridine-4-carboxylic acid]2Fe}2+, were also used for comparison. A series of experiments demonstrate that complex 1 has excellent performance in terms of both catalytic activity and stability. In addition, the faradaic efficiency and turnover frequency (TOF) reach 95.0% and 2.8 s-1, respectively. An overpotential of ca. 490 mV is obtained at pH 1.5. Density functional theory (DFT) calculations indicate that dehydrogenation is the potential-determining step (PDS) in water oxidation. Complex 1 has a lower free energy barrier in this process than 2 and 3. High-valent Fe species are further proven in 1 by spectroelectrochemical measurements, which are crucial in promoting water oxidation. This study is expected to contribute to the development of homogeneous water oxidation catalysis under acidic and neutral conditions.

20.
Proc Natl Acad Sci U S A ; 119(36): e2205562119, 2022 09 06.
Article in English | MEDLINE | ID: mdl-36037332

ABSTRACT

Hydrogen peroxide (H2O2) molecules play important roles in many green chemical reactions. However, the high activation energy limits their application efficiency, and there is still huge controversy about the activation path of H2O2 molecules over the presence of *OOH intermediates. Here, we confirmed the formation of the key species *OOH in the heterogeneous system, via in situ shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS), isotope labeling, and theoretical calculation. In addition, we found that compared with *H2O2, *OOH was more conducive to the charge transfer behavior with the catalyst and the activation of an O-O bond. Furthermore, we proposed to improve the local coordination structure and electronic density of the YFeO3 catalyst by regulating the surface relaxation with Ti modification so as to reduce the activation barrier of H2O2 and to improve the production efficiency of •OH. As a result, the kinetics rates of the Fenton-like (photo-Fenton) reaction had been significantly increased several times. The •OH free radical activity mechanism and molecular transformation pathways of 4-chloro phenol (4-CP) were also revealed. This may provide a clearer vision for the further study of H2O2 activation and suggest a means of designing catalysts for efficient H2O2 activation.


Subject(s)
Hydrogen Peroxide , Photochemical Processes , Catalysis , Hydrogen Peroxide/chemistry , Iron/chemistry , Light , Phenol
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