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1.
Sci Rep ; 14(1): 23550, 2024 Oct 09.
Article in English | MEDLINE | ID: mdl-39384833

ABSTRACT

Accurate runoff forecasting is of great significance for water resource allocation flood control and disaster reduction. However, due to the inherent strong randomness of runoff sequences, this task faces significant challenges. To address this challenge, this study proposes a new SMGformer runoff forecast model. The model integrates Seasonal and Trend decomposition using Loess (STL), Informer's Encoder layer, Bidirectional Gated Recurrent Unit (BiGRU), and Multi-head self-attention (MHSA). Firstly, in response to the nonlinear and non-stationary characteristics of the runoff sequence, the STL decomposition is used to extract the runoff sequence's trend, period, and residual terms, and a multi-feature set based on 'sequence-sequence' is constructed as the input of the model, providing a foundation for subsequent models to capture the evolution of runoff. The key features of the input set are then captured using the Informer's Encoder layer. Next, the BiGRU layer is used to learn the temporal information of these features. To further optimize the output of the BiGRU layer, the MHSA mechanism is introduced to emphasize the impact of important information. Finally, accurate runoff forecasting is achieved by transforming the output of the MHSA layer through the Fully connected layer. To verify the effectiveness of the proposed model, monthly runoff data from two hydrological stations in China are selected, and eight models are constructed to compare the performance of the proposed model. The results show that compared with the Informer model, the 1th step MAE of the SMGformer model decreases by 42.2% and 36.6%, respectively; RMSE decreases by 37.9% and 43.6% respectively; NSE increases from 0.936 to 0.975 and from 0.487 to 0.837, respectively. In addition, the KGE of the SMGformer model at the 3th step are 0.960 and 0.805, both of which can maintain above 0.8. Therefore, the model can accurately capture key information in the monthly runoff sequence and extend the effective forecast period of the model.

2.
J Cancer Res Clin Oncol ; 150(10): 445, 2024 Oct 05.
Article in English | MEDLINE | ID: mdl-39367929

ABSTRACT

PURPOSE: The aim of this study was to determine whether preoperative body mass index (BMI) was associated with postoperative morbidity after laparoscopic liver resection (LLR) for hepatocellular carcinoma (HCC). METHODS: A total of three groups of patients were categorized based on preoperative BMI: low-BMI (≤ 18.4 kg/m2), normal-BMI (18.5-24.9 kg/m2) and high-BMI (≥ 25.0 kg/m2). Baseline clinicopathological characteristics, operative variables, and postoperative 30-day mortality and morbidity were recorded and compared among the three groups. The independent risk factors for postoperative morbidity, including surgical site infection (SSI), were identified using univariate and multivariate analyses. RESULTS: Among 226 included patients, 20 (8.8%), 122 (54%), and 84 (37.2%) patients had low, normal, and high BMI, respectively. There were no significant differences in postoperative 30-day mortality rates in patients with low BMI and high BMI compared with those with normal BMI (5% and 1.2% vs. 0%, P = 0.141 and P = 0.408, respectively). However, postoperative morbidity rates were significantly higher in patients with low BMI and high BMI compared to those with normal BMI (40% and 32.1% vs. 17.2%, P = 0.032 and P = 0.020, respectively). According to multivariate analysis, both low and high BMI were independent risk factors of increased postoperative morbidity (OR: 5.03, 95% CI: 1.02-25.6, P = 0.047, and OR: 4.53, 95% CI: 1.75-12.8, P = 0.003, respectively). Low and high BMI were also identified as independent risk factors of increased postoperative SSI rates (OR: 6.25, 95% CI: 1.60-23.8, P = 0.007, and OR: 2.89, 95% CI: 1.04-8.77, P = 0.047, respectively). CONCLUSION: A higher incidence of postoperative morbidity including SSI after LLR for HCC was found in low-BMI and high-BMI patients compared to normal-BMI patients. CLINICAL TRIALS REGISTRATION: Not applicable because this is a retrospective observational study.


Subject(s)
Body Mass Index , Carcinoma, Hepatocellular , Hepatectomy , Laparoscopy , Liver Neoplasms , Postoperative Complications , Humans , Carcinoma, Hepatocellular/surgery , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/mortality , Liver Neoplasms/surgery , Liver Neoplasms/pathology , Male , Female , Hepatectomy/adverse effects , Retrospective Studies , Laparoscopy/adverse effects , Middle Aged , Risk Factors , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Aged , Morbidity , Adult
3.
Inorg Chem ; 2024 Oct 11.
Article in English | MEDLINE | ID: mdl-39392342

ABSTRACT

Polyoxometalates (POMs) are esteemed for their remarkable stability and exceptionally high proton conductivity, rendering them ripe for extensive exploration owing to their research significance. Herein, we synthesized two bimolybdenum-capped {AlMoVI8MoV6O44} cluster-based coordination polymers through a solvothermal method. Single-crystal X-ray diffraction analysis elucidates that H[(H2bimb)3(AlMoVI8MoV6O44)] [bimb = 1,4-bis(imidazole-1-ylmethyl)benzene, compound 1] is the POMs-organic supramolecular structure. The introduction of zinc ions into the reaction environment facilitated the connection of initially dispersed ligands, which yielded the well-ordered structure H3[Zn2(bimb)4(AlMoVI8MoV6O44)]·4H2O (compound 2) with a layer distance of 11.8 Å. The proton conductivities (σ) of two compounds were measured under conditions of 85 °C and 98% relative humidity (RH), resulting in values of 3.89 × 10-2 and 4.76 × 10-2 S·cm-1, respectively. This study presents a novel approach to fabricating POMs as proton conductors through structural design and manufacturing adjustments.

4.
Am J Surg ; 238: 115988, 2024 Sep 24.
Article in English | MEDLINE | ID: mdl-39342882

ABSTRACT

PURPOSE: To examine the relationship between microvascular invasion (MVI) grading severity and long-term outcomes in early-stage hepatocellular carcinoma (HCC) patients undergoing laparoscopic liver resection (LLR). METHODS: Patients who had LLR for early-stage HCC were enrolled. According to the grading severity of MVI, patients were classified into M0, M1 and M2. Recurrence-free survival (RFS) and overall survival (OS) among the groups were compared. Univariate and multivariate Cox regression analyses were performed to identify independent risk factors of OS and RFS. RESULTS: Among 233 patients, MVI grading as M0, M1, and M2 accounts for 122 (52.4 â€‹%), 84 (36 â€‹%), and 27 (11.6 â€‹%) patients, respectively. The median OS and RFS in patients with M0, M1, and M2 were 84.9, 40.1, and 25.2 months; and 76.9, 27.0, and 18.8 months, respectively. Multivariable analyses identified both M1 and M2 to be independent risk factors for OS and RFS. CONCLUSION: Grading severity of MVI was independently associated with RFS and OS after LLR for early-stage HCC. Patients with MVI, especially those with M2, should receive stringent recurrence surveillance and active adjuvant therapy.

5.
Small ; : e2404552, 2024 Aug 06.
Article in English | MEDLINE | ID: mdl-39106240

ABSTRACT

Oxygen evolution reaction is the essential anodic reaction for water splitting. Designing tunable electronic structures to overcome its slow kinetics is an effective strategy. Herein, the molecular ammonium iron sulfate dodecahydrate is employed as the precursor to synthesize the C, N, S triatomic co-doped Fe(Al)OOH on Ni foam (C,N,S-Fe(Al)OOH-NF) with asymmetric electronic structure. Both in situ oxygen vacancies and their special electronic configuration enable the electron transfer between the d-p orbitals and get the increase of OER activity. Density functional theory calculation further indicates the effect of electronic structure on catalytic activity and stability at the oxygen vacancies. In alkaline solution, the catalyst C,N,S-Fe(Al)OOH-NF shows good catalytic activity and stability for water splitting. For OER, the overpotential of 10 mA cm-2 is 264 mV, the tafel slope is 46.4 mV dec-1, the HER overpotential of 10 mA cm-2 is 188 mV, the tafel slope is 59.3 mV dec-1. The stability of the catalyst can maintain ≈100 h. This work has extraordinary implications for understanding the mechanistic relationship between electronic structure and catalytic activity for designing friendly metal (oxy)hydroxide catalysts.

6.
Angew Chem Int Ed Engl ; 63(42): e202408096, 2024 Oct 14.
Article in English | MEDLINE | ID: mdl-39083343

ABSTRACT

Systematically orchestrating fundamental building blocks into intricate high-dimensional molecular assemblies at molecular level is imperative for multifunctionality integration. However, this remains a formidable task in crystal engineering due to the dynamic nature of inorganic building blocks. Herein, we develop a multi-template-guided strategy to control building blocks. The coordination modes of ligands and the spatial hindrance of anionic templates are pivotal in dictating the overall structures. Flexible multi-dentate linkers selectively promote the formation of oligomeric assembly ([TeO3(Mo2O2S2)3O2(OH)(C5O2H7)3]4- {TeMo6}) into tetrahedral cages ([(TeO3)4(Mo2O2S2)12(OH)12(C9H9O4P)6]8- {Te4Mo24} and [(AsO4)4(Mo2O2S2)12(OH)12(C9H9O6)4]12- {As4Mo24}), while steric hindrance from anionic templates further assists in assembling cages into an open quadruply twisted Möbius nanobelt ([(C6H5O3P)8(Mo2O2S2)24(OH)24(C8H10O4)12]16- {P8Mo48}). Among these structures, the hydrophilic-hydrophobic hybrid cage {Te4Mo24} emerges as an exemplary molecular model for proton conduction and serves as a prototype for humidity gradient-based power generators (HGPGs). The Te4Mo24-PVDF-based HGPG (PVDF=Poly(vinylidene fluoride)) exhibits notable stability and power generation, yielding an open-circuit voltage of 0.51 V and a current density of 77.8 nA cm-2 at room temperature and 90 % relative humidity (RH). Further insights into the interactions between water molecules and microscale molecules within the generator are achieved through molecular dynamics simulations. This endeavor unveils a universal strategy for synthesizing multifunctional integration molecules.

7.
Angew Chem Int Ed Engl ; 63(22): e202402943, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38529715

ABSTRACT

Porous aromatic frameworks (PAFs) show promising potential in anionic conduction due to their high stability and customizable functionality. However, the insolubility of most PAFs presents a significant challenge in their processing into membranes and subsequent applications. In this study, continuous PAF membranes with adjustable thickness were successfully created using liquid-solid interfacial polymerization. The rigid backbone and the stable C-C coupling endow PAF membrane with superior chemical and dimensional stabilities over most conventional polymer membranes. Different quaternary ammonium functionalities were anchored to the backbone through flexible alkyl chains with tunable length. The optimal PAF membrane exhibited an OH- conductivity of 356.6 mS ⋅ cm-1 at 80 °C and 98 % relative humidity. Additionally, the PAF membrane exhibited outstanding alkaline stability, retaining 95 % of its OH- conductivity after 1000 hours in 1 M NaOH. To the best of our knowledge, this is the first application of PAF materials in anion exchange membranes, achieving the highest OH- conductivity and exceptional chemical/dimensional stability. This work provides the possibility for the potential of PAF materials in anionic conductive membranes.

8.
Adv Mater ; 36(25): e2400099, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38481340

ABSTRACT

Multifunctional flexible electronics present tremendous opportunities in the rapidly evolving digital age. One potential avenue to realize this goal is the integration of polyoxometalates (POMs) and ionic liquid-based gels (ILGs), but the challenge of macrophase separation due to poor compatibility, especially caused by repulsion between like-charged units, poses a significant hurdle. Herein, the possibilities of producing diverse and homogenous POMs-containing ionohydrogels by nanoconfining POMs and ionic liquids (ILs) within an elastomer-like polyzwitterionic hydrogel using a simple one-step random copolymerization method, are expanded vastly. The incorporation of polyzwitterions provides a nanoconfined microenvironment and effectively modulates excessive electrostatic interactions in POMs/ILs/H2O blending system, facilitating a phase transition from macrophase separation to a submillimeter scale worm-like microphase-separation system. Moreover, combining POMs-reinforced ionohydrogels with a developed integrated self-powered sensing system utilizing strain sensors and Zn-ion hybrid supercapacitors has enabled efficient energy storage and detection of external strain changes with high precision. This work not only provides guidelines for manipulating morphology within phase-separation gelation systems, but also paves the way for developing versatile POMs-based ionohydrogels for state-of-the-art smart flexible electronics.

9.
Biochem Genet ; 62(2): 814-830, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37460862

ABSTRACT

DTX3L (Deltex E3 ubiquitin ligase 3 L) is an E3 ubiquitin ligase, a member of the deltex family. It is also known as B-lymphoma and BAL-associated protein (BBAP). DTX3L has been proven to play an important role in various tumor development; however, its role in pancreatic cancer remains unknown. So, we analyzed the DTX3L expression in pancreatic cancer based on the TCGA database and verified it in our samples by qRT­PCR and western blot. We identified that DTX3L was highly expressed in pancreatic cancer, and its expression level was significantly negatively correlated with patients' survival. Using CCK8, colony formation, transwell, and wound healing assays, we found that upregulated DTX3L promotes pancreatic cancer cell proliferation, invasion, and migration. Mechanically, DTX3L combined with EGFR (epidermal growth factor receptor) and prevented the ubiquitination degradation of it. Upregulated EGFR activated the FAK/PI3K/Akt pathway and promoted the progression of pancreatic cancer. Moreover, we found that DTX3L can weaken pancreatic cancer cells' sensitivity to chemotherapy using the orthotopic implant tumor model. In conclusion, DTX3L accelerates pancreatic cancer progression by EGFR dependent FAK/PI3K/Akt pathway activation and may become a potential target for pancreatic cancer treatment.

10.
Small ; 20(16): e2308499, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38009797

ABSTRACT

Efficient construction of proton transport channels in proton exchange membranes maintaining conductivity under varied humidity is critical for the development of fuel cells. Covalent organic frameworks (COFs) hold great potential in providing precise and fast ion transport channels. However, the preparation of continuous free-standing COF membranes retaining their inherent structural advantages to realize excellent proton conduction performance is a major challenge. Herein, a zwitterionic COF material bearing positive ammonium ions and negative sulphonic acid ions is developed. Free-standing COF membrane with adjustable thickness is constructed via surface-initiated polymerization of COF monomers. The porosity, continuity, and stability of the membranes are demonstrated via the transmission electron microscopy (TEM), atomic force microscopy (AFM), and scanning electron microscopy (SEM) characterization. The rigidity of the COF structure avoids swelling in aqueous solution, which improves the chemical stability of the proton exchange membranes and improves the performance stability. In the higher humidity range (50-90%), the prepared zwitterionic COF membrane exhibits superior capability in retaining the conductivity compared to COF membrane merely bearing sulphonic acid group. The established strategy shows the potential for the application of zwitterionic COF in the proton exchange membrane fuel cells.

11.
Inorg Chem ; 62(49): 20506-20512, 2023 Dec 11.
Article in English | MEDLINE | ID: mdl-37988635

ABSTRACT

Materials with high proton conductivity have attracted significant attention for their wide-ranging applications in proton exchange membrane fuel cells. However, the design of new and efficient porous proton-conducting materials remains a challenging task. The structure-controllable and highly stable metal phosphates can be synthesized into layer or frame networks to provide proton transport capabilities. Herein, we have successfully synthesized three isomorphic metal phosphovanadates, namely, H2(C2H10N2)2[MII(H2O)2(VIVO)8(OH)4(PO4)4(HPO4)4] (C2H8N2 = 1,2-ethylenediamine; M = Co, Ni, and Cu), by the hydrothermal method employing ethylenediamine as a template. These pure inorganic open frameworks exhibit a cavity width ranging from 6.4 to 7.5 Å. Remarkably, the proton conductivity of compounds 1-3 can reach 1 × 10-2 S·cm-1 at 85 °C and 97% relative humidity (RH), and they can remain stable at high temperatures as well as long-term stability. This work provides a novel strategy for the development and design of porous proton-conducting materials.

12.
Chem Commun (Camb) ; 59(90): 13446-13449, 2023 Nov 09.
Article in English | MEDLINE | ID: mdl-37877313

ABSTRACT

The assembly of [Mo2O2S2]2+ units depends on the configuration of polydentate phosphonic acid templates, leading to novel topologies with enhanced nuclearity and complexity. The variation of the assembled structures also gives rise to distinct proton-conducting properties.

13.
Mol Ther ; 31(9): 2734-2754, 2023 09 06.
Article in English | MEDLINE | ID: mdl-37415332

ABSTRACT

Gastrin-releasing peptide (GRP) binds to its receptor (GRP receptor [GRPR]) to regulate multiple biological processes, but the function of GRP/GRPR axis in acute kidney injury (AKI) remains unknown. In the present study, GRPR is highly expressed by tubular epithelial cells (TECs) in patients or mice with AKI, while histone deacetylase 8 may lead to the transcriptional activation of GRPR. Functionally, we uncovered that GRPR was pathogenic in AKI, as genetic deletion of GRPR was able to protect mice from cisplatin- and ischemia-induced AKI. This was further confirmed by specifically deleting the GRPR gene from TECs in GRPRFlox/Flox//KspCre mice. Mechanistically, we uncovered that GRPR was able to interact with Toll-like receptor 4 to activate STAT1 that bound the promoter of MLKL and CCL2 to induce TEC necroptosis, necroinflammation, and macrophages recruitment. This was further confirmed by overexpressing STAT1 to restore renal injury in GRPRFlox/Flox/KspCre mice. Concurrently, STAT1 induced GRP synthesis to enforce the GRP/GRPR/STAT1 positive feedback loop. Importantly, targeting GRPR by lentivirus-packaged small hairpin RNA or by treatment with a novel GRPR antagonist RH-1402 was able to inhibit cisplatin-induced AKI. In conclusion, GRPR is pathogenic in AKI and mediates AKI via the STAT1-dependent mechanism. Thus, targeting GRPR may be a novel therapeutic strategy for AKI.


Subject(s)
Acute Kidney Injury , Cisplatin , Animals , Mice , Cisplatin/adverse effects , Necroptosis , Acute Kidney Injury/metabolism , Kidney/metabolism , Inflammation/metabolism , Mice, Inbred C57BL
14.
Angew Chem Int Ed Engl ; 62(34): e202304797, 2023 Aug 21.
Article in English | MEDLINE | ID: mdl-37376764

ABSTRACT

Electrocatalytic nitrogen reduction reaction (NRR) under ambient conditions provides an intriguing pathway to convert N2 into NH3 . However, significant kinetic barriers of the NRR at low temperatures in desirable aqueous electrolytes remain a grand challenge due to the inert N≡N bond of the N2 molecule. Herein, we propose a unique strategy for in situ oxygen vacancy construction to address the significant trade-off between N2 adsorption and NH3 desorption by building a hollow shell structured Fe3 C/Fe3 O4 heterojunction coated with carbon frameworks (Fe3 C/Fe3 O4 @C). In the heterostructure, the Fe3 C triggers the oxygen vacancies of the Fe3 O4 component, which are likely active sites for the NRR. The design could optimize the adsorption strength of the N2 and Nx Hy intermediates, thus boosting the catalytic activity for the NRR. This work highlights the significance of the interaction between defect and interface engineering for regulating electrocatalytic properties of heterostructured catalysts for the challenging NRR. It could motivate an in-depth exploration to advance N2 reduction to ammonia.

15.
Angew Chem Int Ed Engl ; 62(30): e202306193, 2023 Jul 24.
Article in English | MEDLINE | ID: mdl-37269225

ABSTRACT

Polyoxometalates (POMs) are considered as promising catalysts with unique redox activity at the molecular level for energy storage. However, eco-friendly iron-oxo clusters with special metal coordination structures have rarely been reported for Li-ion storage. Herein, three novel redox-active tetranuclear iron-oxo clusters have been synthesized using the solvothermal method with different ratios of Fe3+ and SO4 2- . Further, they can serve as anode materials for Li-ion batteries. Among them, cluster H6 [Fe4 O2 (H2 O)2 (SO4 )7 ]⋅H2 O, the stable structure extended by SO4 2- with a unique 1D pore, displays a specific discharge capacity of 1784 mAh g-1 at 0.2 C and good cycle performance (at 0.2 C and 4 C). This is the first instance of inorganic iron-oxo clusters being used for Li-ion storage. Our findings present a new molecular model system with a well-defined structure and offer new design concepts for the practical application of studying the multi-electron redox activity of iron-oxo clusters.

16.
Nat Commun ; 14(1): 2767, 2023 May 13.
Article in English | MEDLINE | ID: mdl-37179336

ABSTRACT

Inorganic salts usually demonstrate simple phasal behaviors in dilute aqueous solution mainly involving soluble (homogeneous) and insoluble (macrophase separation) scenarios. Herein, we report the discovery of complex phase behavior involving multiple phase transitions of clear solution - macrophase separation - gelation - solution - macrophase separation in the dilute aqueous solutions of a structurally well-defined molecular cluster [Mo7O24]6- macroanions with the continuous addition of Fe3+. No chemical reaction was involved. The transitions are closely related to the strong electrostatic interaction between [Mo7O24]6- and their Fe3+ counterions, the counterion-mediated attraction and the consequent charge inversion, leading to the formation of linear/branched supramolecular structures, as confirmed by experimental results and molecular dynamics simulations. The rich phase behavior demonstrated by the inorganic cluster [Mo7O24]6- expands our understanding of nanoscale ions in solution.

17.
J Environ Manage ; 331: 117252, 2023 Apr 01.
Article in English | MEDLINE | ID: mdl-36642052

ABSTRACT

This paper discusses the compensation standard for exhaust pollution and devises a compensation mechanism for Macao's tourism-related transport sector based on an integration of chemical exergy and universal exergy, using data on gasoline consumption by automobile sector retrieved from the transportation industry. The results reveal that: (1) the exergy values of air pollutant emissions increased from 1.53 × 1012 kJ in 2010 to 2.03 × 1012 kJ in 2019 (an increase of 1.33 times), and the exergy of CO, NOx, and SO2 emissions accounted for 77.5%, 20.4% and 2.1% of total exhaust emissions in Macao respectively. (2) In 2019, the monetary value of emission exergy, and the environmental costs of air pollution, were 1.7 times greater than in 2010. (3) If Light Rail Transit is compensated for, then the mean interval's values of the upper and lower limits of the compensation standard are 0.55 USD and 0.05 USD, respectively. When gasoline tax is used as a means of compensation it is necessary to raise its rate by about 8% based on the tax rate. A three-stage bargaining game model is used to provide evidence that this compensation standard is practical and acceptable.


Subject(s)
Air Pollutants , Air Pollution , Air Pollutants/analysis , Gasoline , Macau , Tourism , Air Pollution/analysis , Vehicle Emissions/analysis
18.
J Am Chem Soc ; 145(4): 2243-2251, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36580675

ABSTRACT

Smart molecular actuators have become a cutting-edge theme due to their ability to convert chemical energy into mechanical energy under external stimulations. However, realizing actuation at the molecular level and elucidating the mechanisms for actuating still remain challenging. Herein, we design and fabricate a novel nanoscaled polyoxometalate-based humidity-responsive molecular actuator {Bi8Mo48} through the assembly of [Mo2O2S2]2+ units, transition metals, and flexible phosphonic acid ligands. {Bi8Mo48} exhibits a semi-flexible cage-like architecture with oxygen-rich surfaces and highly negative charges 72-. The nanoscaled molecular actuator shows reversible expansion and contraction behavior under humidity variations due to lattice expansion and contraction induced by hydrogen bonding and solvation interactions between {Bi8Mo48} and water molecules. Molecular dynamics simulation was further employed to study these processes, which provides a fundamental understanding for the mechanism of humidity actuation at the molecular level.

19.
Inorg Chem ; 61(51): 21024-21034, 2022 Dec 26.
Article in English | MEDLINE | ID: mdl-36520449

ABSTRACT

Spatially confined assembly of semimetallic oxyanions (AsO33- and SbO33-) within a [H7P8W48O184]33- (P8W48) macrocycle has afforded three nanoscale polyanions, [{AsIII5O4(OH)3}2(P8W48O184)]32- (As10), [(SbIIIOH)4(P8W48O184)]32- (Sb4), and [(SbIIIOH)8(P8W48O184)]24- (Sb8), which were crystallized as the hydrated mixed-cation salts (Me2NH2)13K7Na2Li10[{AsIII5O4(OH)3}2(P8W48O184)]·32H2O (DMA-KNaLi-As10), K20Li12[(SbIIIOH)4(P8W48O184)]·52H2O (KLi-Sb4), and (Me2NH2)8K6Na5Li5[(SbIIIOH)8(P8W48O184)]·65H2O (DMA-KNaLi-Sb8), respectively. A multitude of solid- and solution-state physicochemical techniques were employed to systematically characterize the structure and composition of the as-made compounds. The polyanion of As10 represents the first example of a semimetal-oxo cluster-substituted P8W48 and accommodates the largest AsIII-oxo cluster in polyoxometalates (POMs) reported to date. The number of incorporated SbO33- groups in Sb4 and Sb8 could be customized by a simple variation of SbIII-containing precursors. Encapsulation of semimetallic oxyanions inside P8W48 sets out a valid strategy not only for the development of host-guest assemblies in POM chemistry but also for their function expansion in emerging applications such as proton-conducting materials, for which DMA-KNaLi-As10 showcases an outstanding conductivity of 1.2 × 10-2 S cm-1 at 85 °C and 70% RH.

20.
ACS Appl Mater Interfaces ; 14(47): 52877-52885, 2022 Nov 30.
Article in English | MEDLINE | ID: mdl-36383757

ABSTRACT

Alkaline water splitting is a highly efficient and clean technology for hydrogen energy generation. However, in alkaline solutions, most catalysts suffer from extreme instability. Herein, a cross-nanostructured N, F, and CO32- codoped iron oxyhydroxide composite (N,F-FeO(OH)-CO3-NF) rich in oxygen defects is designed for water splitting in the alkaline solution. X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations show that the introduction of F and CO32- can induce electron redistribution around the active center Fe, accelerate the four-electron transfer process, and optimize the d-band center, thereby improving the efficiency and stability of HER and OER. In a 1 M KOH solution, N,F-FeO(OH)-CO3-NF only needs the overpotential of 248 mV for OER and the overpotential of 199 mV for HER to reach the current density of 10 mA·cm-2. Meanwhile, it can reach 100 mA·cm-2 current density at 1.55 V vs RHE and maintains a current density of 10 mA·cm-2 for 120 h in a two-electrode electrolytic water device. Compared with bulk hydroxides, the heteroatom and anion codoped composite hydroxides are more stable and have dual functions in the electrolyte solution. This is of great significance for designing a new stable water-splitting electrocatalyst.

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