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1.
Nature ; 617(7961): 519-523, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37198309

RESUMO

During the chlor-alkali process, in operation since the nineteenth century, electrolysis of sodium chloride solutions generates chlorine and sodium hydroxide that are both important for chemical manufacturing1-4. As the process is very energy intensive, with 4% of globally produced electricity (about 150 TWh) going to the chlor-alkali industry5-8, even modest efficiency improvements can deliver substantial cost and energy savings. A particular focus in this regard is the demanding chlorine evolution reaction, for which the state-of-the-art electrocatalyst is still the dimensionally stable anode developed decades ago9-11. New catalysts for the chlorine evolution reaction have been reported12,13, but they still mainly consist of noble metal14-18. Here we show that an organocatalyst with an amide functional group enables the chlorine evolution reaction; and that in the presence of CO2, it achieves a current density of 10 kA m-2 and a selectivity of 99.6% at an overpotential of only 89 mV and thus rivals the dimensionally stable anode. We find that reversible binding of CO2 to the amide nitrogen facilitates formation of a radical species that plays a critical role in Cl2 generation, and that might also prove useful in the context of Cl- batteries and organic synthesis19-21. Although organocatalysts are typically not considered promising for demanding electrochemical applications, this work demonstrates their broader potential and the opportunities they offer for developing industrially relevant new processes and exploring new electrochemical mechanisms.

2.
Nano Lett ; 23(23): 11368-11375, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38047597

RESUMO

The design of catalysts has attracted a great deal of attention in the field of electrocatalysis. The accurate design of the catalysts can avoid an unnecessary process that occurs during the blind trial. Based on the interaction between different metal species, a metallic compound supported by the carbon nanotube was designed. Among these compounds, RhFeP2CX (R-RhFeP2CX-CNT) was found to be in a rich-electron environment at the Fermi level (denoted as a flat Fermi surface), beneficial to the hydrogen evolution reaction (HER). R-RhFeP2CX-CNT exhibits a small overpotential of 15 mV at the current density of 10 mA·cm-2 in acidic media. Moreover, the mass activity of R-RhFeP2CX-CNT is 21597 A·g-1, which also demonstrates the advance of the active sites on R-RhFeP2CX-CNT. Therefore, R-RhFeP2CX-CNT can be an alternative catalyst applied in practical production, and the strategies of a flat Fermi surface will be a reliable strategy for catalyst designing.

3.
Angew Chem Int Ed Engl ; 63(8): e202314382, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38182547

RESUMO

Consuming one of the largest amount of electricity, the chlor-alkali industry supplies basic chemicals for society, which mainly consists of two reactions, hydrogen evolution (HER) and chlorine evolution reaction (CER). Till now, the state-of-the-art catalyst applied in this field is still the dimensional stable anode (DSA), which consumes a large amount of noble metal of Ru and Ir. It is thus necessary to develop new types of catalysts. In this study, an organocatalyst anchored on the single-atom support (SAS) is put forward. It exhibits high catalytic efficiency towards both HER and CER with an overpotential of 21 mV and 20 mV at 10 mA cm-2 . With this catalyst on both electrodes, the energy consumption is cut down by 1.2 % compared with the commercial system under industrial conditions. Based on this novel catalyst and the high activity, the mechanism of modifying non-covalent interaction is demonstrated to be reliable for the catalyst's design. This work not only provides efficient catalysts for the chlor-alkali industry but also points out that the SACs can also act as support, providing new twists for the development of SACs and organic molecules in the next step.

4.
Angew Chem Int Ed Engl ; 63(3): e202315032, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38057563

RESUMO

The oxygen evolution reaction (OER), characterized by a four-electron transfer kinetic process, represents a significant bottleneck in improving the efficiency of hydrogen production from water electrolysis. Consequently, extensive research efforts have been directed towards identifying single-atom electrocatalysts with exceptional OER performance. Despite the comprehensive understanding of the OER mechanism, its application to other valuable synthetic reactions has been limited. Herein, we leverage the MOOH intermediate, a key species in the Mn-N-C single-atom catalyst (Mn-SA@NC), which can be cyclically delivered in the OER. We exploit this intermediate' s capability to facilitate electrophilic transfer with silane, enabling efficient silane oxidation under electrochemical conditions. The SAC electrocatalytic system exhibits remarkable performance with catalyst loadings as low as 600 ppm and an exceptional turnover number of 9132. Furthermore, the catalytic method demonstrates stability under a 10 mmol flow chemistry setup. By serving as an OER electrocatalyst, the Mn-SA@NC drives the entire reaction, establishing a practical Mn SAC-catalyzed organic electrosynthesis system. This synthesis approach not only presents a promising avenue for the utilization of electrocatalytic OER but also highlights the potential of SACs as an attractive platform for organic electrosynthesis investigations.

5.
Angew Chem Int Ed Engl ; 63(27): e202404295, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38649323

RESUMO

Homogeneous electrocatalysts can indirect oxidate the high overpotential substrates through single-electron transfer on the electrode surface, enabling efficient operation of organic electrosynthesis catalytic cycles. However, the problems of this chemistry still exist such as high dosage, difficult recovery, and low catalytic efficiency. Single-atom catalysts (SACs) exhibit high atom utilization and excellent catalytic activity, hold great promise in addressing the limitations of homogeneous catalysts. In view of this, we have employed Fe-SA@NC as an advanced redox mediator to try to change this situation. Fe-SA@NC was synthesized using an encapsulation-pyrolysis method, and it demonstrated remarkable performance as a redox mediator in a range of reported organic electrosynthesis reactions, and enabling the construction of various C-C/C-X bonds. Moreover, Fe-SA@NC demonstrated a great potential in exploring new synthetic method for organic electrosynthesis. We employed it to develop a new electro-oxidative ring-opening transformation of cyclopropyl amides. In this new reaction system, Fe-SA@NC showed good tolerance to drug molecules with complex structures, as well as enabling flow electrochemical syntheses and gram-scale transformations. This work highlights the great potential of SACs in organic electrosynthesis, thereby opening a new avenue in synthetic chemistry.

6.
Acc Chem Res ; 55(18): 2660-2671, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36048514

RESUMO

Cancer vaccines provide an efficient strategy to enhance tumor-specific immune responses by redeploying immune systems. Despite the approval of the first cancer vaccine (Sipuleucel-T) by the U.S. Food and Drug Administration in 2010, most therapeutic cancer vaccines fail in clinical trials. Basically, tumor-specific immune responses rely on not only T-cell but also B-cell immunity, which indicates that cancer vaccines should leverage both arms of the adaptive immune system. For example, CD8+ T cells activated by antigen-presenting cells (APCs) recognize and directly kill tumor cells via peptide-bound major histocompatibility complex (pMHC). B cells recognize antigen with no need of pMHC and require CD4+ T cells for sufficient activation and antibody generation, enabling antibody-mediated nondirect killing on tumor cells. Considering the different mechanisms of T-cell and B-cell activation, the rational design of therapeutic cancer vaccines should consider several factors, including antigen selection and recognition, immune activation, vaccine delivery, and repeatable vaccination, which can be advanced by chemical strategies.In this Account, we summarize our recent contributions to the development of effective T-cell- and B-cell-based therapeutic cancer vaccines. For T-cell-based vaccines, we focus on adjuvants as the key component for controllable APC activation and T-cell priming. Not only synthetic molecular agonists of pattern recognition receptors (PRRs) but also adjuvant nanomaterials were explored to satisfy diversiform vaccine designs. For example, a type of natural cyclic dinucleotide (CDN) that was chemically modified with fluorination and ipsilateral phosphorothioation to activate the stimulator of interferon gene (STING) was found to mediate antitumor responses. It retains structural similarity to the parent CDN scaffold but possesses increased stability, cellular uptake, and immune activation for antitumor treatment. It also facilitates facile conjugation with other agonists, which not only enhances APC-targeting delivery but also balances cellular and humoral antitumor responses. We also explored the intrinsic properties of nanomaterials that allow them to serve as adjuvants. A black phosphorus nanosheet-based nanovaccine was constructed and found to strongly potentiate antigen-specific T-cell antitumor immune responses through multiple immune-potentiating properties, leading to a highly integrated nanomaterial-based adjuvant design. For B-cell-based vaccines, multicomponent and multivalent strategies were applied to improve the immunogenicity. A multicomponent linear vaccine conjugate coordinates helper T (Th) cells and APCs to proliferate and differentiates B cells for enhanced antitumor immunoglobulin G antibody responses. To further improve antigen recognition, clustered designs on a multivalent epitope were applied by generating various structures, including branched lysine-based peptides, natural multivalent scaffold molecules, and self-assembled nanofibers. We also engineered nano- and microvaccine systems to optimize systemic and localized vaccination. A multilayer-assembled nanovaccine successfully integrated antigens and multiple agonists to modulate APC activation. A DNA hydrogel contributed to the control of APC's immune behaviors, including cell recruitment, activation, and migration, and induced robust antitumor responses as an all-in-one designable platform. In this Account, by summarizing strategies for both T-cell- and B-cell-based vaccine design, we not only compare the differences but also address the intrinsic uniformity between such vaccine designs and further discuss the potential of a combined T-cell- and B-cell-based vaccine, which highlights the applicability and feasibility of chemical strategies.


Assuntos
Vacinas Anticâncer , Neoplasias , Adjuvantes Imunológicos/uso terapêutico , Linfócitos T CD8-Positivos , Vacinas Anticâncer/uso terapêutico , DNA , Epitopos , Humanos , Hidrogéis , Imunoglobulina G , Interferons , Lisina , Neoplasias/tratamento farmacológico , Fósforo , Receptores de Reconhecimento de Padrão
7.
Chem Soc Rev ; 51(18): 7944-7970, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-35996977

RESUMO

Immunotherapy is recognised as an attractive method for the treatment of cancer, and numerous treatment strategies have emerged over recent years. Investigations of the tumour microenvironment (TME) have led to the identification of many potential therapeutic targets and methods. However, many recently applied immunotherapies are based on previously identified strategies, such as boosting the immune response by combining commonly used stimulators, and the release of drugs through changes in pH. Although methodological improvements such as structural optimisation and combining strategies can be undertaken, applying those novel targets and methods in immunotherapy remains an important goal. In this review, we summarise the latest research on the TME, and discuss how small molecules, immune cells, and their interactions with tumour cells can be regulated in the TME. Additionally, the techniques currently employed for delivery of these agents to the TME are also mentioned. Strategies to modulate cell phenotypes and interactions between immune cells and tumours are mainly discussed. We consider both modulatory and targeting methods aiming to bridge the gap between the TME and chemical modulation thereof.


Assuntos
Neoplasias , Microambiente Tumoral , Humanos , Imunidade , Imunomodulação , Imunoterapia/métodos , Neoplasias/tratamento farmacológico
8.
Zhongguo Zhong Yao Za Zhi ; 48(9): 2316-2324, 2023 May.
Artigo em Chinês | MEDLINE | ID: mdl-37282860

RESUMO

Patchoulol is an important sesquiterpenoid in the volatile oil of Pogostemon cablin, and is also considered to be the main contributing component to the pharmacological efficacy and fragrance of P. cablin oil, which has antibacterial, antitumor, antioxidant, and other biological activities. Currently, patchoulol and its essential oil blends are in high demand worldwide, but the traditional plant extraction method has many problems such as wasting land and polluting the environment. Therefore, there is an urgent need for a new method to produce patchoulol efficiently and at low cost. To broaden the production method of patchouli and achieve the heterologous production of patchoulol in Saccharomyces cerevisiae, the patchoulol synthase(PS) gene from P. cablin was codon optimized and placed under the inducible strong promoter GAL1 to transfer into the yeast platform strain YTT-T5, thereby obtaining strain PS00 with the production of(4.0±0.3) mg·L~(-1) patchoulol. To improve the conversion rate, this study used protein fusion method to fuse SmFPS gene from Salvia miltiorrhiza with PS gene, leading to increase the yield of patchoulol to(100.9±7.4) mg·L~(-1) by 25-folds. By further optimizing the copy number of the fusion gene, the yield of patchoulol was increased by 90% to(191.1±32.7) mg·L~(-1). By optimizing the fermentation process, the strain was able to achieve a patchouli yield of 2.1 g·L~(-1) in a high-density fermentation system, which was the highest yield so far. This study provides an important basis for the green production of patchoulol.


Assuntos
Óleos Voláteis , Pogostemon , Sesquiterpenos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Sesquiterpenos/metabolismo , Óleos Voláteis/metabolismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-35819407

RESUMO

To better understand the effects of endophytic bacteria on halophytes, a bacteria that produced indole-3-acetic acid and 1-aminocyclopropane-1-carboxylic acid deaminase, designated HD2P242T, was isolated from a shoot of Kalidium cuspidatum collected in Tumd Right Banner, Inner Mongolia, PR China. The cells of strain HD2P242T were Gram-stain-negative, strictly aerobic, motile by gliding, non-spore-forming and rod-shaped. Strain HD2P242T grew at pH 6.0-9.0 (optimum, pH 7.0) and 10-45 °C (optimum 37 °C), in the presence of 0-8 % (w/v) NaCl (optimum, 4 %). The strain was positive for oxidase and catalase. The phylogenetic trees based on the 16S rRNA gene sequences and the whole genome sequences both showed that strain HD2P242T clustered with Sinomicrobium pectinilyticum 5DNS001T and S. oceani SCSIO 03483T, and had 95.6, 94.3 and <94.3 % 16S rRNA gene similarities to S. pectinilyticum 5DNS001T, S. oceani SCSIO 03483T and all the other current type strains. Strain HD2P242T contained menaquinone 6 as its sole respiratory quinone. Its major polar lipids were phosphatidylethanolamine, two unidentified aminolipids, two unidentified phospholipids and an unidentified lipid. The major fatty acids were iso-C17 : 0, iso-C16 : 0 3-OH, anteiso-C17 : 0 and summed feature 6 (C19 : 1 ω9c and/or C19 : 1 ω11c). The genome consisted of a 5 364 211 bp circular chromosome, with a G+C content of 45.1 mol%, predicting 4391 coding sequence genes, 47 tRNA genes and two rRNA operons. The average nucleotide identity based on blast and the digital DNA-DNA hybridization values of strain HD2P242T with S. oceani SCSIO 03483T and S. pectinilyticum 5DNS001T were 73.8 and 77.0%, and 22.3 and 22.2%, respectively. The comparative genome analysis showed that the pan-genomes of strain HD2P242T and three Sinomicrobium type strains possessed 4236 clusters, whereas the core genome possessed 2162 clusters, which accounted for 52.3 % of all the clusters. The genomic analysis revealed that all four Sinomicrobium members could utilize d-glucose by the glycolysis-gluconeogenesis pathway or the pentose phosphate pathway. The tricarboxylic acid cycle was utilized as a metabolic centre. The phylogenetic, physiological and phenotypic characteristics allowed the discrimination of strain HD2P242T from its phylogenetic relatives. Therefore, Sinomicrobium kalidii sp. nov. is proposed, and the type strain is HD2P242T (=CGMCC 1.19025T=KCTC 92136T).


Assuntos
Chenopodiaceae , Plantas Tolerantes a Sal , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Endófitos/genética , Ácidos Graxos/química , Ácidos Indolacéticos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Microbiologia do Solo
10.
Chem Rev ; 120(20): 11420-11478, 2020 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-32914967

RESUMO

Personalized cancer vaccines (PCVs) are reinvigorating vaccine strategies in cancer immunotherapy. In contrast to adoptive T-cell therapy and checkpoint blockade, the PCV strategy modulates the innate and adaptive immune systems with broader activation to redeploy antitumor immunity with individualized tumor-specific antigens (neoantigens). Following a sequential scheme of tumor biopsy, mutation analysis, and epitope prediction, the administration of neoantigens with synthetic long peptide (SLP) or mRNA formulations dramatically improves the population and activity of antigen-specific CD4+ and CD8+ T cells. Despite the promising prospect of PCVs, there is still great potential for optimizing prevaccination procedures and vaccine potency. In particular, the arduous development of tumor-associated antigen (TAA)-based vaccines provides valuable experience and rational principles for augmenting vaccine potency which is expected to advance PCV through the design of adjuvants, delivery systems, and immunosuppressive tumor microenvironment (TME) reversion since current personalized vaccination simply admixes antigens with adjuvants. Considering the broader application of TAA-based vaccine design, these two strategies complement each other and can lead to both personalized and universal therapeutic methods. Chemical strategies provide vast opportunities for (1) exploring novel adjuvants, including synthetic molecules and materials with optimizable activity, (2) constructing efficient and precise delivery systems to avoid systemic diffusion, improve biosafety, target secondary lymphoid organs, and enhance antigen presentation, and (3) combining bioengineering methods to innovate improvements in conventional vaccination, "smartly" re-educate the TME, and modulate antitumor immunity. As chemical strategies have proven versatility, reliability, and universality in the design of T cell- and B cell-based antitumor vaccines, the union of such numerous chemical methods in vaccine construction is expected to provide new vigor and vitality in cancer treatment.


Assuntos
Vacinas Anticâncer/imunologia , Neoplasias/terapia , Adjuvantes Imunológicos , Animais , Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/química , Humanos , Imunoterapia , Neoplasias/imunologia
11.
Angew Chem Int Ed Engl ; 61(52): e202213318, 2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36199272

RESUMO

The simultaneous presence of two active metal centres in diatomic catalysts (DACs) leads to the occurrence of specific interactions between active sites. Such interactions, referred to as long-range interactions (LRIs), play an important role in determining the rate and selectivity of a reaction. The optimal combination of metal centres must be determined to achieve the targeted efficiency. To date, various types of DACs have been synthesised and applied in electrochemistry. However, LRIs have not been systematically summarised. Herein, the regulation, mechanism, and electrocatalytic applications of LRIs are comprehensively summarised and discussed. In addition to the basic information above, the challenges, opportunities, and future development of LRIs in DACs are proposed in order to present an overall view and reference for future research.

12.
Angew Chem Int Ed Engl ; 61(16): e202200366, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35118786

RESUMO

Chlorine evolution reaction has been applied in the production since a century ago. After times of evolution, it has been widely realized by the electrocatalytic process on anode nowadays. However, the anode applied in production contains a large amount of precious metal, increasing the cost. It is thus an opportunity to apply sub-nano catalysts in this field. By regulating the tip effect (TE) of the catalyst, it was discovered that the oxidized sub-nano iridium clusters supported by titanium carbide exhibit much higher efficiency than the single-atom one, which demonstrates the significance of modifying the electronic interaction. Moreover, it exhibits a ≈20 % decrease of the electricity, ≈98 % selectivity towards chlorine evolution reaction, and high durability of over 350 h. Therefore, this cluster catalyst performs great potential in applying in the practical production and the comprehension of the tip effect on different types of catalysts is also pushed to a higher level.

13.
Angew Chem Int Ed Engl ; 61(40): e202209749, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36000816

RESUMO

Improving the stability of sensitive catalytic systems is an emerging research topic in the catalysis field. However, the current design of heterogeneous catalysts mainly improves their catalytic performance. This paper presents a single-atom catalyst (SAC) strategy to improve the cobalt-catalysed fluorination of acyl chlorides. A stable Co-F intermediate can be formed through the oxidative fluorination of Co1 -N4 @NC SAC, which can replace the unstable high-valent cobalt catalytic system and avoid the use of phosphine ligands. In the SAC system, KF can be employed as a fluorinating reagent to replace the AgF, which can be applied to various substrates and scale-up conversion with high turnover numbers (TON=1.58×106 ). This work also shows that inorganic SACs have tremendous potential for organofluorine chemistry, and it provides a good reference for follow-up studies on the structure-activity relationship between catalyst design and chemical reaction mechanisms.

14.
Angew Chem Int Ed Engl ; 61(10): e202117661, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35034424

RESUMO

Covalent organic frameworks (COF) possess a robust and porous crystalline structure, making them an appealing candidate for energy storage. Herein, we report an exfoliated polyimide COF composite (P-COF@SWCNT) prepared by an in situ condensation of anhydride and amine on the single-walled carbon nanotubes as advanced anode for potassium-ion batteries (PIBs). Numerous active sites exposed on the exfoliated frameworks and the various open pathways promote the highly efficient ion diffusion in the P-COF@SWCNT while preventing irreversible dissolution in the electrolyte. During the charging/discharging process, K+ is engaged in the carbonyls of imide group and naphthalene rings through the enolization and π-K+ effect, which is demonstrated by the DFT calculation and XPS, ex-situ FTIR, Raman. As a result, the prepared P-COF@SWCNT anode enables an incredibly high reversible specific capacity of 438 mA h g-1 at 0.05 A g-1 and extended stability. The structural advantage of P-COF@SWCNT enables more insights into the design and versatility of COF as an electrode.

15.
Angew Chem Int Ed Engl ; 61(4): e202114450, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-34767294

RESUMO

The exploitation of highly efficient carbon dioxide reduction (CO2 RR) electrocatalyst for methane (CH4 ) electrosynthesis has attracted great attention for the intermittent renewable electricity storage but remains challenging. Here, N-heterocyclic carbene (NHC)-ligated copper single atom site (Cu SAS) embedded in metal-organic framework is reported (2Bn-Cu@UiO-67), which can achieve an outstanding Faradaic efficiency (FE) of 81 % for the CO2 reduction to CH4 at -1.5 V vs. RHE with a current density of 420 mA cm-2 . The CH4 FE of our catalyst remains above 70 % within a wide potential range and achieves an unprecedented turnover frequency (TOF) of 16.3 s-1 . The σ donation of NHC enriches the surface electron density of Cu SAS and promotes the preferential adsorption of CHO* intermediates. The porosity of the catalyst facilitates the diffusion of CO2 to 2Bn-Cu, significantly increasing the availability of each catalytic center.

16.
J Am Chem Soc ; 143(37): 15453-15461, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34506145

RESUMO

Ligands are the most commonly used means to control the regioselectivity of organic reactions. It is very important to develop new regioselective control methods for organic synthesis. In this study, we designed and synthesized a single-atomic-site catalyst (SAC), namely, Cu1-TiC, with strong electronic metal-support interaction (EMSI) effects by studying various reaction mechanisms. π cloud back-donation to the alkyne on the metal catalytic intermediate was enhanced during the reaction by using transient electron-rich characteristics. In this way, the reaction achieved highly linear-E-type regioselective conversion of electronically unbiased alkynes and completely avoided the formation of branched isomers (ln:br >100:1, TON up to 612, 3 times higher than previously recorded). The structural elements of the SACs were designed following the requirements of the synthesis mechanism. Every element in the catalyst played an important role in the synthesis mechanism. This demonstrated that the EMSI, which is normally thought to be responsible for the improvement in catalytic efficiency and durability in heterogeneous catalysis, now first shows exciting potential for regulating the regioselectivity in homogeneous catalysis.

17.
Small ; 17(32): e2102010, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34216100

RESUMO

There are still many problems that hinder the development of sodium-ion batteries (SIBs), including poor rate performance, short-term cycle lifespan, and inferior low-temperature property. Herein, excellent Na-storage performance in fluorophosphate (Na3 V2 (PO4 )2 F3 ) cathode is achieved by lattice regulation based on charge balance theory. Lattice regulation of aliovalent Mn2+ for V3+ increases both electronic conductivity and Na+ -migration kinetics. Because of the maintaining of electrical neutrality in the material, aliovalent Mn2+ -introduced leads to the coexistence of V3+ and V4+ from charge balance theory. It decreases the particle size and improves the structural stability, suppressing the large lattice distortion during cathode reaction processes. These multiple effects enhance the specific capacity (123.8 mAh g-1 ), outstanding high-rate (68% capacity retention at 20 C), ultralong cycle (only 0.018% capacity attenuation per cycle over 1000 cycles at 1 C) and low-temperature (96.5% capacity retention after 400 cycles at -25 °C) performances of Mn2+ -induced Na3 V1.98 Mn0.02 (PO4 )2 F3 when used as cathode in SIBs. Importantly, a feasible sodium-ion full battery is assembled, achieving outstanding rate capability and cycle stability. The strategy of aliovalent ion-induced lattice regulation constructs cathode materials with superior performances, which is available to improve other electrode materials for energy storage systems.

18.
Angew Chem Int Ed Engl ; 60(35): 19085-19091, 2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34155750

RESUMO

It is still of great difficulty to develop the non-platinum catalyst with high catalytic efficiency towards hydrogen evolution reaction via the strategies till now. Therefore, it is necessary to develop the new methods of catalyst designing. Here, we put forward the catalyst designed by the electronic metal-support interaction (EMSI), which is demonstrated to be a reliable strategy to find out the high-efficiency catalyst. We carried out the density functional theory calculation first to design the proper EMSI of the catalyst. We applied the model of M1-M2-X (X=C, N, O) during the calculation. Among the catalysts we chose, the EMSI of Rh1TiC, with the active sites of Rh1-Ti2C2, is found to be the most proper one for HER. The electrochemical experiment further demonstrated the feasibility of the EMSI strategy. The single atomic site catalyst of Rh1-TiC exhibits higher catalytic efficiency than that of state-of-art Pt/C. It achieves a small overpotential of 22 mV and 86 mV at the at the current density of 10 mA cm-2 and 100 mA cm-2 in acid media, with a Tafel slope of 25 mV dec-1 and a mass activity of 54403.9 mA cm-2 mgRh -1 (vs. 192.2 mA cm-2 mgPt -1 of Pt/C). Besides, it also shows appealing advantage in energy saving compared with Pt/C (≈20 % electricity consuming decrease at 2 kA m-2 ) Therefore, we believe that the strategy of regulating EMSI can act as a possible way for achieving the high catalytic efficiency on the next step of SACs.

19.
Angew Chem Int Ed Engl ; 60(51): 26837-26846, 2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34636126

RESUMO

Although ether-based electrolytes have been extensively applied in anode evaluation of batteries, anodic instability arising from solvent oxidability is always a tremendous obstacle to matching with high-voltage cathodes. Herein, by rational design for solvation configuration, the fully coordinated ether-based electrolyte with strong resistance against oxidation is reported, which remains anodically stable with high-voltage Na3 V2 (PO4 )2 O2 F (NVPF) cathode under 4.5 V (versus Na+ /Na) protected by an effective interphase. The assembled graphite//NVPF full cells display superior rate performance and unprecedented cycling stability. Beyond that, the constructed full cells coupling the high-voltage NVPF cathode with hard carbon anode exhibit outstanding electrochemical performances in terms of high average output voltage up to 3.72 V, long-term cycle life (such as 95 % capacity retention after 700 cycles) and high energy density (247 Wh kg-1 ). In short, the optimized ether-based electrolyte enriches systematic options, the ability to maintain oxidative stability and compatibility with various anodes, exhibiting attractive prospects for application.

20.
Med Res Rev ; 40(3): 1117-1141, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31793026

RESUMO

Since being discovered in 2008, the STING (stimulator of interferon genes) pathway has gradually been recognized as a central and promising target for immunotherapy. The STING pathway can be stimulated by cyclic dinucleotides (CDNs), leading to the type I interferons (IFN) production for immunotherapy for cancer or other diseases. However, the negative charges, hydrophilicity, and instability of CDNs have hindered their further applications. In addition, chronic activation of the STING pathway has been found to be involved in autoimmune diseases as IFN overproduction. Thus, research and development of STING agonists and inhibitors has been a hot field for the treatment of several diseases. The past several years, especially 2018, has seen increasingly rapid advances in this field. Here, this review summarizes the synthesis and modification of CDNs, the identification of nonnucleotide agonists, the recent progress in delivery systems and the medical applications, such as personalized vaccine adjuvants, in detail. In addition, in this review, we summarize the STING inhibitors' advances from two aspects, covalent, and noncovalent inhibitors.


Assuntos
Imunoterapia/métodos , Proteínas de Membrana/agonistas , Proteínas de Membrana/antagonistas & inibidores , Animais , Cátions , Linhagem Celular Tumoral , Ensaios Clínicos como Assunto , Citosol/metabolismo , Sistemas de Liberação de Medicamentos , Desenho de Fármacos , Humanos , Hidrogéis/química , Concentração de Íons de Hidrogênio , Lipossomos/química , Camundongos , Neoplasias/imunologia , Neoplasias/terapia , Oligonucleotídeos Fosforotioatos/química , Polímeros/química
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