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1.
J Am Chem Soc ; 144(21): 9254-9263, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35535584

RESUMO

Promoting the oxygen evolution reaction (OER) with saline water is highly desired to realize seawater splitting. This requires OER catalysts to resist serious corrosion and undesirable chloride oxidation. We introduce a 5d transition metal, Ir, to develop a monolayer NiIr-layered double hydroxide (NiIr-LDH) as the catalyst with enhanced OER performance for seawater splitting. The NiIr-LDH catalyst delivers 500 mA/cm2 at only 361 mV overpotential with ∼99% O2 Faradaic efficiency in alkaline seawater, which is more active than commercial IrO2 (763 mV, 23%) and the best known OER catalyst NiFe-LDH (530 mV, 92%). Moreover, it shows negligible activity loss at up to 650 h chronopotentiometry measurements at an industrial level (500 mA/cm2), while commercial IrO2 and NiFe-LDH rapidly deactivated within 0.2 and 10 h, respectively. The incorporation of Ir into the Ni(OH)2 layer greatly altered the electron density of Ir and Ni sites, which was revealed by X-ray absorption fine structure and density functional theory (DFT) calculations. Coupling the electrochemical measurements and in situ Raman spectrum with DFT calculations, we further confirm that the generation of rate-limiting intermediate *O and *OOH species was accelerated on Ni and Ir sites, respectively, which is responsible for the high seawater splitting performance. Our results also provide an opportunity to fabricate LDH materials containing 5d metals for applications beyond seawater splitting.

3.
Nat Commun ; 13(1): 2721, 2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35581214

RESUMO

The pursuit of selective two-electron oxygen reduction reaction to H2O2 in acids is demanding and largely hampered by the lack of efficient non-precious-metal-based electrocatalysts. Metal macrocycles hold promise, but have been relatively underexplored. Efforts are called for to promote their inherent catalytic activities and/or increase the surface exposure of active sites. In this contribution, we perform the high-throughput computational screening of thirty-two different metalloporphyrins by comparing their adsorption free energies towards key reaction intermediates. Cobalt porphyrin is revealed to be the optimal candidate with a theoretical overpotential as small as 40 mV. Guided by the computational predictions, we prepare hydrogen-bonded cobaltoporphyrin frameworks in order to promote the solution accessibility of catalytically active sites for H2O2 production in acids. The product features an onset potential at ~0.68 V, H2O2 selectivity of >90%, turnover frequency of 10.9 s-1 at 0.55 V and stability of ~30 h, the combination of which clearly renders it stand out from existing competitors for this challenging reaction.

4.
Angew Chem Int Ed Engl ; : e202202089, 2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35460153

RESUMO

Rational synthesis of hydrogen-bonded organic frameworks (HOFs) with predicted structure has been a long-term challenge. Herein, by using the efficient, simple, low-cost, and scalable mechanosynthesis, we demonstrate that reticular chemistry is applicable to HOF assemblies based on building blocks with different geometry, connectivity, and functionality. The obtained crystalline HOFs show uniform nano-sized morphology, which is challenging or unachievable for conventional solution-based methods. Furthermore, the one-pot mechanosynthesis generated a series of Pd@HOF composites with noticeably different CO oxidation activities. In situ DRIFTS studies indicate that the most efficient composite, counterintuitively, shows the weakest CO affinity to Pd sites while the strongest CO affinity to HOF matrix, revealing the vital role of porous matrix to the catalytic performance. This work paves a new avenue for rational synthesis of HOF and HOF-based composites for broad application potential.

5.
Angew Chem Int Ed Engl ; : e202203955, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35441462

RESUMO

In natural photosynthesis, the architecture of multiproteins integrates more chromophores than redox centers and simultaneously creates a well-controlled environment around the active site. Herein, we demonstrate that these features can be emulated in a prototype hydrogen-bonded organic framework (HOF) through simply varying the proportion of metalated porphyrin in the structure. Further studies demonstrate that changing the metalloporphyrin content not only realizes a fine tuning of the photosensitizer/catalyst ratio, but also alters the microenvironment surrounding the active site and the charge separation efficiency. As a result, the obtained material achieves the challenging overall CO2 reduction with a high HCOOH production rate (29.8 µmol g-1 h-1 , scavenger free), standing out from existing competitors. This work unveils that the degree of metalation is vital to the catalytic activity of the porphryinic framework, presenting as a new strategy to optimize the performance of heterogeneous catalysts.

6.
ACS Appl Mater Interfaces ; 14(18): 21050-21058, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35476406

RESUMO

Photocatalytic CO2 reduction is one of the most cost-effective and environmentally friendly techniques of converting CO2 into high-value compounds and/or fuels. However, the performance of most current photocatalytic CO2 reduction catalysts is less than satisfactory for practical applications. Here, we synthesized a heterogeneous structure by integrating Cu2O and a porphyrin hydrogen-bonded organic framework (PFC-45), which was then fabricated into a thin-film catalyst on carbolic paper (CP) using a facile electrophoretic deposition technology. With improved electron-hole separation efficiency and visible-light-harvesting ability, this film (PFC-45/Cu2O@CP) significantly enhanced CO2-to-CO photoreduction, exceeding 2.4 and 3.2 times that of PFC-45@CP and PFC-45/Cu2O particles, respectively. Remarkably, PFC-45/Cu2O@CP also exhibited high selectivity (99%) and outstanding activity (11.81 µmol g-1 h-1) for photocatalytic CO2 reduction in pure water without any sacrificial agent. This work demonstrates a new strategy to design photocatalysts for efficient CO2 reduction.

7.
World J Clin Cases ; 10(6): 1998-2006, 2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35317165

RESUMO

BACKGROUND: Mutations that occur in the ABCB4 gene, which encodes multidrug-resistant protein 3, underlie the occurrence of progressive familial intrahepatic cholestasis type 3 (PFIC3). Clinical signs of intrahepatic cholestasis due to gene mutations typically first appear during infancy or childhood. Reports of PFIC3 occurring in adults are rare. CASE SUMMARY: This is a case study of a 32-year-old infertile female Chinese patient with a 15-year history of recurrent abnormal liver function. Her primary clinical signs were elevated levels of alkaline phosphatase and γ-glutamyl transpeptidase. Other possible reasons for liver dysfunction were eliminated in this patient, resulting in a diagnosis of PFIC3. The diagnosis was confirmed using gene detection and histological analyses. Assessments using genetic sequencing analysis indicated the presence of two novel heterozygous mutations in the ABCB4 gene, namely, a 2950C>T; p.A984V mutation (exon 24) and a 667A>G; p.I223V mutation (exon 7). After receiving ursodeoxycholic acid (UDCA) treatment, the patient's liver function indices improved, and she successfully became pregnant by in vitro fertilization. However, the patient developed intrahepatic cholestasis of pregnancy in the first trimester. Fortunately, treatment with UDCA was safe and effective. CONCLUSION: These novel ABCB4 heterozygous mutations have a variety of clinical phenotypes. Continued follow-up is essential for a comprehensive understanding of PFIC3.

8.
Small ; 18(16): e2200407, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35266311

RESUMO

Previous studies on syntheses of metal-organic frameworks (MOFs) for photocatalytic CO2 reduction are mainly focused on the exquisite control over the net topology and the functionality of metal clusters/organic building blocks. This contribution demonstrates that the rational design of MOF-based photocatalyst can be further extended to the hierarchical structure at micrometer scales well beyond the conventional MOF design at the molecular level. By taking advantage of the disparity of two selective MOFs in nucleation kinetics, a hierarchical core-shell MOF@MOF structure is successfully constructed through a simple one-pot synthesis. Besides inheriting the high porosity, crystallinity, and robustness of parent MOFs, the obtained heterojunction exhibits extended photoresponse, optimized band alignment with large overpotential, and greatly enhanced photogenerated charge separation, which would be hardly realized by the merely molecular-level assembly. As a result, the challenging overall CO2 photoreduction is achieved, which generates a record high HCOOH production (146.0 µmol/g/h) without using any sacrificial reagents. Moreover, the core-shell structure exhibits a more effective use of photogenerated electrons than the individual MOFs. This work shows that harnessing the hierarchical architecture of MOFs present a new and effective alternative to tuning the photocatalytic performance at a mesoscopic level.

9.
Angew Chem Int Ed Engl ; 61(6): e202115854, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34877789

RESUMO

Under topological guidance, the self-assembly process based on a tetratopic porphyrin synthon results in a hydrogen-bonded organic framework (HOF) with the predicted square layers topology (sql) but unsatisfied stability. Strikingly, simply introducing a transition metal in the porphyrin center does not change the network topology but drastically causes noticeable change on noncovalent interaction, orbital overlap, and molecular geometry, therefore ultimately giving rise to a series of metalloporphyrinic HOFs with high surface area, and excellent stability (intact after being soaked in boiling water, concentrated HCl, and heated to 270 °C). On integrating both photosensitizers and catalytic sites into robust backbones, this series of HOFs can effectively catalyze the photoreduction of CO2 to CO, and their catalytic performances greatly depend on the chelated metal species in the porphyrin centers. This work enriches the library of stable functional HOFs and expands their applications in photocatalytic CO2 reduction.

10.
Research (Wash D C) ; 2021: 9874273, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34778792

RESUMO

The poor electrical conductivity of metal-organic frameworks (MOFs) has been a stumbling block for its applications in many important fields. Therefore, exploring a simple and effective strategy to regulate the conductivity of MOFs is highly desired. Herein, anionic guest molecules are incorporated inside the pores of a cationic MOF (PFC-8), which increases its conductivity by five orders of magnitude while maintaining the original porosity. In contrast, the same operation in an isoreticular neutral framework (PFC-9) does not bring such a significant change. Theoretical studies reveal that the guest molecules, stabilized inside pores through electrostatic interaction, play the role of electron donors as do in semiconductors, bringing in an analogous n-type semiconductor mechanism for electron conduction. Therefore, we demonstrate that harnessing electrostatic interaction provides a new way to regulate the conductivity of MOFs without necessarily altering the original porous structure. This strategy would greatly broaden MOFs' application potential in electronic and optoelectronic technologies.

11.
Dalton Trans ; 50(47): 17499-17505, 2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34812820

RESUMO

The construction of heterostructures is a universal method to hinder the radiative recombination of hot electrons and hot holes, which can effectively enhance the photothermal effect of semiconductors. In this work, a one-pot method was employed to prepare a composite named Bi2Se3@ZIF-8 NPs, which incredibly increased the photothermal conversion efficiency of Bi2Se3 NPs. The temperature elevation of Bi2Se3@ZIF-8 NPs was almost double that of the Bi2Se3 NPs; specifically, the temperature of the irradiated Bi2Se3@ZIF-8 NPs was strikingly increased to 130 °C within 6 seconds, and finally stabilized at 165 °C. Furthermore, the photothermal conversion ability was maintained over multiple irradiation cycles, which endows this composite with great potential to be an excellent photothermal agent.

12.
Angew Chem Int Ed Engl ; 60(49): 25701-25707, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34477299

RESUMO

Exploration of effective ways to integrate various functional species into hydrogen-bonded organic frameworks (HOFs) is critically important for their applications but highly challenging. In this study, according to the "bottle-around-ship" strategy, core-shell heterostructure of upconversion nanoparticles (UCNPs) and HOFs was fabricated for the first time via a ligand-grafting stepwise method. The UCNPs "core" can effectively upconvert near-infrared (NIR) irradiation (980 nm) into visible light (540 nm and 653 nm), which further excites the perylenediimide-based HOF "shell" through resonance energy transfer. In this way, the nanocomposite inherits the high porosity, excellent photothermal and photodynamic efficiency, NIR photoresponse from two parent materials, achieving intriguing NIR-responsive bacterial inhibition toward Escherichia coli. This study may shed light on the design of functional HOF-based composite materials, not only enriching the HOF library but also broadening the horizon of their potential applications.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Imidas/farmacologia , Nanoestruturas/química , Perileno/análogos & derivados , Fármacos Fotossensibilizantes/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Ligação de Hidrogênio , Imidas/síntese química , Imidas/química , Raios Infravermelhos , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Perileno/síntese química , Perileno/química , Perileno/farmacologia , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Propriedades de Superfície
13.
Dalton Trans ; 50(25): 8680-8684, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34152331

RESUMO

A series of metallarectangles 1-5 were synthesized by the selective combination of (p-cymene)Ru-corner, bis(ß-diketone) arms and bifunctional pyridyl linkers. They exhibited a very rare phenomenon of haloalkane-induced fluorescence enhancement.

14.
Chemistry ; 27(42): 10957-10965, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-33884685

RESUMO

Porous materials have been investigated as efficient photochromic platforms for detecting hazardous radiation, while the utilization of hydrogen bonded organic frameworks (HOFs) in this field has remained intact. Herein, two HOFs were synthesized through self-assembly of tetratopic viologen ligand and formic acid (PFC-25, PFC-26), as a new class of "all-organic" radiochromic smart material, opening a gate for HOFs in this field. PFC-26 is active upon both X-ray and UV irradiation, while PFC-25 is only active upon X-ray irradiation. The same building block yet different radiochromic behaviors of PFC-25 and PFC-26 allow us to gain a deep mechanistic understanding of the factors that control the detection specificity. Theoretical and experimental studies reveal that the degree of π-conjugation of viologen ligand is highly related to the threshold energy of triggering a charge transfer, therefore being a vital factor for the particularity of radiochromic materials. Thanks to its convenient processibility, nanoparticle size, and UV silence, PFC-25 can be further fabricated into a portable naked-eye sensor for X-ray detection, which shows obvious color change with the merits of high transmittance contrast, good sensitivity (reproducible dose threshold of 3.5 Gy), and excellent stability. The work exhibits the promising practical potentials of HOF materials in photochromic technology.


Assuntos
Hidrogênio , Viologênios , Ligação de Hidrogênio , Raios X
15.
Mol Divers ; 25(2): 701-710, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32008141

RESUMO

A rapid and efficient protocol to fused pentacyclic compounds, the chromeno[3',4':3,4]pyrido[2,1-a]isoquinolines, via a diastereoselective 1,4-dipolar cycloaddition reaction of isoquinoline, dialkyl acetylenedicarboxylates, and 3-acetyl coumarins, is described.


Assuntos
Isoquinolinas/síntese química , Ácidos Carboxílicos/química , Cumarínicos/química , Reação de Cicloadição , Isoquinolinas/química
16.
Adv Mater ; 32(48): e2005912, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33124716

RESUMO

Functionalization of hydrogen-bonded organic frameworks (HOFs) for specific applications has been a long-lasting challenge in HOF materials. Here, an efficient way to integrate functional species in the HOF structure through constructing an anionic framework is presented. The obtained HOFs, taking PFC-33 (PFC = porous materials from FJIRSM,CAS) as an example, integrate a porphyrin photosensitizer as a porous backbone and a commercial biocide as counterions in the structure. The permanent channels and the electrostatic interaction between the framework and the counterions provide PFC-33 ion-responsive biocide-release behavior in various physiological environments, thus exhibiting synergistic photodynamic and chemical antimicrobial efficiency. The unbonded carboxyl groups residing on the HOF surface further allow for manipulating the interfacial interaction between the PFC-33 and the polymer matrix for membrane fabrication. Therefore, a polyHOF membrane with high stability, desired flexibility, and good permeability is obtained, which demonstrates noticeable bacterial inhibition toward Escherichia coli. This study may shed light on the functionalization of HOF materials for broad application potentials.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Membranas Artificiais , Compostos Orgânicos/química , Compostos Orgânicos/farmacologia , Ligação de Hidrogênio , Eletricidade Estática
17.
Angew Chem Int Ed Engl ; 59(52): 23641-23648, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-32926542

RESUMO

It is still a great challenge to achieve high selectivity of CH4 in CO2 electroreduction reactions (CO2 RR) because of the similar reduction potentials of possible products and the sluggish kinetics for CO2 activation. Stabilizing key reaction intermediates by single type of active sites supported on porous conductive material is crucial to achieve high selectivity for single product such as CH4 . Here, Cu2 O(111) quantum dots with an average size of 3.5 nm are in situ synthesized on a porous conductive copper-based metal-organic framework (CuHHTP), exhibiting high selectivity of 73 % towards CH4 with partial current density of 10.8 mA cm-2 at -1.4 V vs. RHE (reversible hydrogen electrode) in CO2 RR. Operando infrared spectroscopy and DFT calculations reveal that the key intermediates (such as *CH2 O and *OCH3 ) involved in the pathway of CH4 formation are stabilized by the single active Cu2 O(111) and hydrogen bonding, thus generating CH4 instead of CO.

18.
Angew Chem Int Ed Engl ; 59(50): 22392-22396, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-32885555

RESUMO

Hydrogen-bonded organic frameworks (HOFs) possess various merits, such as high porosity, tunable structure, facile modification, and ready regeneration. These properties have yet to be explored in the context of new functional HOF materials. The facile and inexpensive electrophoretic deposition (EPD) method applied in this study generated a transparent HOF film at room temperature in just 2 min and is applicable to other HOFs. The resulting film exhibited reversible electrochromism with the advantage of long cycle life (>500 cycles). More strikingly, this all-organic film could be readily regenerated (through rinsing with DMF and redeposition) and showed tunable electrochromic behavior (through low-cost postsynthetic modification) with the ability to undergo successive color changes, which is difficult to achieve with conventional electrochromic materials. An electrochromic device was manufactured to further demonstrate the application potential of the film.

19.
Chem Commun (Camb) ; 56(54): 7459-7462, 2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32495788

RESUMO

A facile method, post-synthetic exchange of modulators (PSEm), has been demonstrated here to prepare chiral metal-organic frameworks for enantioseparation. Based on this method, three chiral porous Zr-based metal-organic frameworks have been prepared through exchanging the coordinated modulators on metal clusters of MOFs with commercially available chiral carboxylic acid molecules. In addition, the obtained materials show enantioselectivity toward three different enantiomers, which presents a proof of concept for the design of MOF materials for enantioseparation by an easy and low-cost method.

20.
ACS Appl Mater Interfaces ; 12(26): 29854-29860, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483962

RESUMO

Developing a noncontact ratiometric luminescent temperature sensor with high sensitivity, widely available emission range, and reliable performance is a challenge in materials science. Herein, we demonstrated that this goal can be achieved by fabricating a lanthanide-functionalized hydrogen-bonded organic framework film (named the Eu@HOF-TCBP film). The unbonded carboxylic groups that existed in the structure not only enable lanthanide ions to bind with the framework for bringing dual emission but also allow for preparing a hydrogen-bonded organic framework (HOF) film through the facile electrophoretic deposition. The obtained film exhibits ratiometric temperature sensing performance in the range of 297-377 K with a maximum relative sensitivity of 5.787% K-1 and shows repeated use without sensitivity loss. Moreover, the material can be easily recycled and refabricated with consistent performance, demonstrating its unique merits of easy recyclability and regeneration as an HOF material. We believe that the reported strategies for preparing a dual-emitting HOF and fabricating a thin film will open a window for HOF applications.

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