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1.
Angew Chem Int Ed Engl ; : e202416367, 2024 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-39392381

RESUMO

The addition of polar functional groups to porous structures is an effective strategy for increasing the ability of metal-organic frameworks (MOFs) to capture CO2 by enhancing interactions between the dipoles of the polar functional groups and the quadrupoles of CO2. However, the potential of MOFs grafted to polar functional group to activate CO2 has not been investigated in the context of CO2 electrolysis. In this study, we report a mixed-ligand strategy to incorporate various functional groups in the MOFs. We found that substituents with strong polarity led to increased catalytic performance of electrochemical CO2 reduction for these polarized MOFs. Both experimental and theoretical evidence indicates that the presence of polar functional groups induces a charge redistribution in the micropores of MOFs. We have shown that higher electron densities of sp2-carbon atoms in benzimidazolate ligands reduces the energy barrier to generate *COOH, which is simultaneously controlled by the mass transfer of CO2. Our research offers an effective method of disrupting local electron neutrality in the pores of electrocatalysts/supports to activate CO2 under electrochemical conditions.

2.
Angew Chem Int Ed Engl ; 63(8): e202316029, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38168107

RESUMO

RuO2 is one of the benchmark electrocatalysts used as the anode material in proton exchange membrane water electrolyser. However, its long-term stability is compromised due to the participation of lattice oxygen and metal dissolution during oxygen evolution reaction (OER). In this work, weakened covalency of Ru-O bond was tailored by introducing tensile strain to RuO6 octahedrons in a binary Ru-Sn oxide matrix, prohibiting the participation of lattice oxygen and the dissolution of Ru, thereby significantly improving the long-term stability. Moreover, the tensile strain also optimized the adsorption energy of intermediates and boosted the OER activity. Remarkably, the RuSnOx electrocatalyst exhibited excellent OER activity in 0.1 M HClO4 and required merely 184 mV overpotential at a current density of 10 mA cm-2 . Moreover, it delivered a current density of 10 mA cm-2 for at least 150 h with negligible potential increase. This work exemplifies an effective strategy for engineering Ru-based catalysts with extraordinary performance toward water splitting.

3.
Chemistry ; 25(63): 14358-14363, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31423674

RESUMO

The development of sodium-ion batteries (SIBs) is hindered by the rapid reduction in reversible capacity of carbon-based anode materials. Outside-in doping of carbon-based anodes has been extensively explored. Nickel and NiS2 particles embedded in nitrogen and sulfur codoped porous graphene can significantly improve the electrochemical performance. Herein a built-in heteroatom "self-doping" of albumen-derived graphene for sodium storage is reported. The built-in sulfur and nitrogen in albumen act as the doping source during the carbonization of proteins. The sulfur-rich proteins in albumen can also guide the doping and nucleation of nickel sulfide nanoparticles. Additionally, the porous architecture of the carbonized proteins is achieved through removable KCl/NaCl salts (medium) under high-temperature melting conditions. During the carbonization process, nitrogen can also reduce the carbonization temperature of thermally stable carbon materials. In this work, the NS-graphene delivered a specific capacity of 108.3 mAh g-1 after 800 cycles under a constant current density of 500 mA g-1 . In contrast, the Ni/NiS2 /NS-graphene maintained a specific capacity of 134.4 mAh g-1 ; thus the presence of Ni/NiS2 particles improved the electrochemical performance of the whole composite.

4.
Clin Transl Oncol ; 24(11): 2231-2240, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35852680

RESUMO

PURPOSE: Although lorlatinib, the third generation of echinoderm microtubule protein 4-anaplastic lymphoma kinase (EML4-ALK) tyrosine kinase inhibitor (TKI), overcame the previous generation ALK-TKIs' drug resistance problems, but the mechanism of lorlatinib resistance remained unclear. Furthermore, optimal chemotherapy for lorlatinib-resistant non-small cell lung cancer (NSCLC) patients was still unknown. METHODS: A lorlatinib-resistant NSCLC cell line SNU-2535LR was generated by gradually increasing dose of lorlatinib to crizotinib-resistant cell line SNU-2535 in vitro. To study the resistance mechanism of SNU-2535LR cells, we applied CCK-8 assay to detect the sensitivity of crizotinib and the reverse effect of APR-246, a p53 activator, on lorlatinib-induced resistance and different chemotherapy drugs to SNU-2535LR cells. We also detected the expressions of EML4-ALK-related proteins of SNU-2535LR cells via western blot.Please confirm that author names have been identified correctly and are presented in the right order.Dear Editor:     I have carefully confirmed that the author names have been identified correctly and are presented in right order.Thank you very much!                                                                     Your sincerely BoXie RESULTS: The sensitivity of SNU-2535LR cells to lorlatinib was decreased significantly than that of SNU-2535 cells. EML4-ALK fusion was decreased both at protein level and DNA level in SNU-2535LR cells. More interesting, the crizotinib-resistant mutation ALK p.G1269A disappeared, while new TP53 mutation emerged in SNU-2535LR cells. APR-246 can reverse the lorlatinib resistance in SNU-2535LR cells, with a reversal index of 4.768. Compared with SNU-2535 cells, the sensitivity of SNU-2535LR cells to gemcitabine, docetaxel and paclitaxel was significantly increased (P < 0.05), but decreased to cisplatin (P < 0.05). CONCLUSION: This study demonstrated that the combination of p53 protein agonist and lorlatinib may provide a new therapeutic strategy for NSCLC patients with lorlatinib resistance and TP53 mutation. Furthermore, the results also provide guidance for selecting optimal chemo-regimens for NSCLC patients after ALK-TKIs failure.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Aminopiridinas , Quinase do Linfoma Anaplásico/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular , Cisplatino/uso terapêutico , Crizotinibe/uso terapêutico , Docetaxel/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Lactamas , Lactamas Macrocíclicas/farmacologia , Lactamas Macrocíclicas/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Proteínas dos Microtúbulos/genética , Mutação , Paclitaxel/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Pirazóis , Proteína Supressora de Tumor p53/genética
5.
Small Methods ; 6(4): e2101511, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35175002

RESUMO

Electronic structure of single-atom catalysts (SACs) is critical for bifunctional oxygen electrocatalysis by adjusting the binding energy in oxygen-containing intermediates. However, the regulation of electronic structure has always been a challenge to improve catalytic reactivity. Herein, by introducing a heterogenous metal, the electronic structure through a direct bonding interaction to the active center atom is effectively adjusted. Partial charge transfer between the two atoms optimizes the binding energy of intermediates and reducing the energy barrier of the catalytic reaction. Theoretical calculations confirm these effects and the uniform distribution of 3d orbitals, leading to the improvement of bifunctional oxygen electrocatalytic reactivity. Benefiting from these attributes, the as-constructed bifunctional catalyst enables outstanding electrocatalytic performances in both oxygen reduction and hydrogen oxidation in various energy storage systems. The generality and expandability of this strategy is demonstrated by further successful development of other dual-metal catalysts systems with various active metals.

6.
ACS Appl Mater Interfaces ; 12(36): 40204-40212, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32794688

RESUMO

Electro- and photocatalytic hydrogen evolution reaction (e-HER and p-HER) are two promising strategies to produce green hydrogen fuel from water. High intrinsic activity, sufficient active sites, fast charge-transfer capacity, and good optoelectronic properties must be taken into consideration simultaneously in pursuit of an ideal bifunctional catalyst. Here, platinum atomic clusters embedded in defects of TiO2 nanocrystals/graphene nanosheets (Pt-T/G) are reported as a bifunctional catalyst for electro- and photocatalytic hydrogen evolution reaction (e-HER and p-HER). High activity is delivered due to the charge transfer from the other part of the catalyst to the active center (Pt2-O4-Tix), decreasing the activation energy of the rate-limiting step, which is revealed by synchrotron X-ray absorption spectroscopy, photoelectrochemical measurements, and simulated calculations. In regard to e-HER, it outperforms the commercial 20 wt % Pt/C catalyst by a factor of 17.5 on Pt mass basis, allowing for a 93% reduction in Pt loadings. In regard to p-HER, it achieves photocatalytic efficiency (686.8 µmol h-1) without any attenuation in 9 h.

7.
Research (Wash D C) ; 2020: 5714349, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32676587

RESUMO

The shuttle effect hinders the practical application of lithium-sulfur (Li-S) batteries due to the poor affinity between a substrate and Li polysulfides (LiPSs) and the sluggish transition of soluble LiPSs to insoluble Li2S or elemental S. Here, we report that Ni hexatomic clusters embedded in a nitrogen-doped three-dimensional (3D) graphene framework (Ni-N/G) possess stronger interaction with soluble polysulfides than that with insoluble polysulfides. The synthetic electrocatalyst deployed in the sulfur cathode plays a multifunctional role: (i) selectively adsorbing the polysulfides dissolved in the electrolyte, (ii) expediting the sluggish liquid-solid phase transformations at the active sites as electrocatalysts, and (iii) accelerating the kinetics of the electrochemical reaction of multielectron sulfur, thereby inhibiting the dissolution of LiPSs. The constructed S@Ni-N/G cathode delivers an areal capacity of 9.43 mAh cm-2 at 0.1 C at S loading of 6.8 mg cm-2, and it exhibits a gravimetric capacity of 1104 mAh g-1 with a capacity fading rate of 0.045% per cycle over 50 cycles at 0.2 C at S loading of 2.0 mg cm-2. This work opens a rational approach to achieve the selective adsorption and expediting of polysulfide transition for the performance enhancement of Li-S batteries.

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