scholarly journals Interfacial-confined coordination to single-atom nanotherapeutics

2022 ◽  
Vol 13 (1) ◽  
Author(s):  
Limei Qin ◽  
Jie Gan ◽  
Dechao Niu ◽  
Yueqiang Cao ◽  
Xuezhi Duan ◽  
...  
Keyword(s):  
Therapeutic Strategy ◽  
Single Atom ◽  
Oxygen Species ◽  
High Quality ◽  
Efficient Energy ◽  
Coordination Strategy ◽  
Single Atoms ◽  
Highly Active ◽  
Narrow Bandgap ◽  
Catalytic Sites

AbstractPursuing and developing effective methodologies to construct highly active catalytic sites to maximize the atomic and energy efficiency by material engineering are attractive. Relative to the tremendous researches of carbon-based single atom systems, the construction of bio-applicable single atom materials is still in its infancy. Herein, we propose a facile and general interfacial-confined coordination strategy to construct high-quality single-atom nanotherapeutic agent with Fe single atoms being anchored on defective carbon dots confined in a biocompatible mesoporous silica nanoreactor. Furthermore, the efficient energy conversion capability of silica-based Fe single atoms system has been demonstrated on the basis of the exogenous physical photo irradiation and endogenous biochemical reactive oxygen species stimulus in the confined mesoporous network. More importantly, the highest photothermal conversion efficiency with the mechanism of increased electron density and narrow bandgap of this single atom structure in defective carbon was proposed by the theoretical DFT calculations. The present methodology provides a scientific paradigm to design and develop versatile single atom nanotherapeutics with adjustable metal components and tune the corresponding reactions for safe and efficient tumor therapeutic strategy.

scholarly journals Coherent single-atom superradiance

Science ◽  
2017 ◽  
Vol 359 (6376) ◽  
pp. 662-666 ◽  
Author(s):  
Junki Kim ◽  
Daeho Yang ◽  
Seung-hoon Oh ◽  
Kyungwon An
Keyword(s):  
Quality Factor ◽  
Position Control ◽  
Single Atom ◽  
Atomic Ensemble ◽  
Atom Number ◽  
High Quality ◽  
Nanohole Array ◽  
Single Atoms ◽  
Quantum Phenomenon ◽  
Array Aperture

Superradiance is a quantum phenomenon emerging in macroscopic systems whereby correlated single atoms cooperatively emit photons. Demonstration of controlled collective atom-field interactions has resulted from the ability to directly imprint correlations with an atomic ensemble. Here we report cavity-mediated coherent single-atom superradiance: Single atoms with predefined correlation traverse a high–quality factor cavity one by one, emitting photons cooperatively with the N atoms that have already gone through the cavity (N represents the number of atoms). Enhanced collective photoemission of N-squared dependence was observed even when the intracavity atom number was less than unity. The correlation among single atoms was achieved by nanometer-precision position control and phase-aligned state manipulation of atoms by using a nanohole-array aperture. Our results demonstrate a platform for phase-controlled atom-field interactions.

Tunable Carbon Surface from Mono- to Multi-Metallic Single Atoms

2020 ◽  
Author(s):  
Weihong Lai ◽  
Heng Wang ◽  
Quan jiang ◽  
Zichao Yan ◽  
Hanwen Liu ◽  
...  
Keyword(s):  
Synergistic Effects ◽  
Structural Evolution ◽  
Charge Compensation ◽  
Catalytic Reactions ◽  
Single Atom ◽  
Carbon Surface ◽  
Hydrogen Electrode ◽  
Single Atoms ◽  
Mass Activity ◽  
Co Doped

<p>Herein, we develop a non-selective charge compensation strategy to prepare multi-single-atom doped carbon (MSAC) in which a sodium p-toluenesulfonate (PTS-Na) doped polypyrrole (S-PPy) polymer is designed to anchor discretionary mixtures of multiple metal cations, including iron (Fe<sup>3+</sup>), cobalt (Co<sup>3+</sup>), ruthenium (Ru<sup>3+</sup>), palladium (Pd<sup>2+</sup>), indium (In<sup>3+</sup>), iridium (Ir<sup>2+</sup>), and platinum (Pt<sup>2+</sup>) . As illustrated in Figure 1, the carbon surface can be tuned with different level of compositional complexities, including unary Pt<sub>1</sub>@NC, binary (MSAC-2, (PtFe)<sub>1</sub>@NC), ternary (MSAC-3, (PtFeIr)<sub>1</sub>@NC), quaternary (MSAC-4, (PtFeIrRu)<sub>1</sub>@NC), quinary (MSAC-5, (PtFeIrRuCo)<sub>1</sub>@NC), senary (MSAC-6, (PtFeIrRuCoPd)<sub>1</sub>@NC), and septenary (MSAC-7, (PtFeIrRuCoPdIn)<sub>1</sub>@NC) samples. The structural evolution of carbon surface dictates the activities of both ORR and HER. The senary MSAC-6 achieves the ORR mass activity of 18.1 A·mg<sub>metal</sub><sup>-1</sup> at 0.9 V (Vs reversible hydrogen electrode (RHE)) over 30K cycles, which is 164 times higher than that of commercial Pt/C. The quaternary MSAC-4 presented a comparable HER catalytic capability with that of Pt/C. These results indicate that the highly complexed carbon surface can enhance its ability over general electrochemical catalytic reactions. The mechanisms regarding of the ORR and HER activities of the alternated carbon surface are also theoretically and experimentally investigated in this work, showing that the synergistic effects amongst the co-doped atoms can activate or inactivate certain single-atom sites.</p>

scholarly journals Insights on forming N,O-coordinated Cu single-atom catalysts for electrochemical reduction CO2 to methane

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yanming Cai ◽  
Jiaju Fu ◽  
Yang Zhou ◽  
Yu-Chung Chang ◽  
Qianhao Min ◽  
...  
Keyword(s):  
Energy Barrier ◽  
Active Sites ◽  
Theoretical Calculations ◽  
High Energy ◽  
Single Atom ◽  
Faradaic Efficiency ◽  
High Energy Barrier ◽  
Catalytic Sites ◽  
Electron Reduction ◽  
First Time

AbstractSingle-atom catalysts (SACs) are promising candidates to catalyze electrochemical CO2 reduction (ECR) due to maximized atomic utilization. However, products are usually limited to CO instead of hydrocarbons or oxygenates due to unfavorable high energy barrier for further electron transfer on synthesized single atom catalytic sites. Here we report a novel partial-carbonization strategy to modify the electronic structures of center atoms on SACs for lowering the overall endothermic energy of key intermediates. A carbon-dots-based SAC margined with unique CuN2O2 sites was synthesized for the first time. The introduction of oxygen ligands brings remarkably high Faradaic efficiency (78%) and selectivity (99% of ECR products) for electrochemical converting CO2 to CH4 with current density of 40 mA·cm-2 in aqueous electrolytes, surpassing most reported SACs which stop at two-electron reduction. Theoretical calculations further revealed that the high selectivity and activity on CuN2O2 active sites are due to the proper elevated CH4 and H2 energy barrier and fine-tuned electronic structure of Cu active sites.

Improving peroxymonosulfate activation by copper ion-saturated adsorbent-based single atom catalysts for the degradation of organic contaminants: electron-transfer mechanism and the key role of Cu single atoms

2021 ◽  
Author(s):  
Jingwen Pan ◽  
Baoyu Gao ◽  
Pijun Duan ◽  
Kangying Guo ◽  
Muhammad Akram ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Organic Contaminants ◽  
High Salinity ◽  
Copper Ion ◽  
Single Atom ◽  
Electron Transfer Mechanism ◽  
Persulfate Oxidation ◽  
Single Atoms ◽  
Oxidation Technology

Nonradical pathway-based persulfate oxidation technology is considered to be a promising method for high-salinity organic wastewater treatment.

Nanotubular OMS-2 Supported Single-Atom Platinum Catalysts Highly Active for Benzene Oxidation

2021 ◽  
Author(s):  
Xiuqing Hao ◽  
Lingyun Dai ◽  
Jiguang Deng ◽  
Yuxi Liu ◽  
Lin Jing ◽  
...  
Keyword(s):  
Platinum Catalysts ◽  
Single Atom ◽  
Benzene Oxidation ◽  
Highly Active

Highly active and stable Ir nanoclusters derived from Ir1/MgAl2O4 single-atom catalysts

2021 ◽  
Vol 154 (13) ◽  
pp. 131105
Author(s):  
Jingyi Yang ◽  
Jingcai Zhang ◽  
Qike Jiang ◽  
Yang Su ◽  
Yitao Cui ◽  
...  
Keyword(s):  
Single Atom ◽  
Highly Active

Synergy of Single Atoms Pd and Oxygen Vacancies on In2O3 for Highly Selective C1 Oxygenates Production from Methane under Visible Light

2021 ◽  
Author(s):  
Lei Luo ◽  
Lei Fu ◽  
Huifen Liu ◽  
Youxun Xu ◽  
Jialiang Xing ◽  
...  
Keyword(s):  
Oxygen Vacancies ◽  
Single Atom ◽  
Electron Transfer Pathway ◽  
Mild Conditions ◽  
Single Atoms ◽  
Primary Products ◽  
Critical Issues ◽  
Regulation Of Activity ◽  
Visible Irradiation ◽  
Dft Modelling

Abstract Methane (CH4) oxidation to high value chemicals under mild conditions through photocatalysis is a sustainable and appealing pathway, nevertheless confronting the critical issues on both conversion and selectivity. Herein, under visible irradiation (420 nm), the synergy of palladium (Pd) atom cocatalyst and oxygen vacancies (OVs) on In2O3 nanorods enabled superior photocatalytic CH4 activation by O2. The optimised catalyst reached ca. 100 µmol·h− 1 of C1 oxygenates, with a selectivity of primary products (CH3OH and CH3OOH) up to 82.5 %. Mechanism investigation elucidated that such superior photocatalysis was induced by the dedicated function of Pd single atoms and oxygen vacancies on boosting hole and electron transfer pathway, respectively. O2 was proven to be the only oxygen source for CH3OH production, while H2O acted as the promoter for efficient CH4 activation through ·OH production and facilitated product desorption as indicated by DFT modelling. This work thus provides new understandings on simultaneous regulation of activity and selectivity by the significant synergy of single atom cocatalysts and oxygen vacancies.

scholarly journals Receptor-mediated mitophagy regulates EPO production and protects against renal anemia

eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Guangfeng Geng ◽  
Jinhua Liu ◽  
Changlu Xu ◽  
Yandong yan Pei ◽  
Linbo Chen ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Quality Control ◽  
Therapeutic Strategy ◽  
Inflammatory Responses ◽  
Critical Role ◽  
Renal Anemia ◽  
Inflammatory Factors ◽  
Oxygen Species ◽  
Mitochondrial Quality Control ◽  
Hematopoietic Disorders

Erythropoietin (EPO) drives erythropoiesis and is secreted mainly by the kidney upon hypoxic or anemic stress. The paucity of EPO production in renal EPO-producing cells (REPs) causes renal anemia, one of the most common complications of chronic nephropathies. Although mitochondrial dysfunction is commonly observed in several renal and hematopoietic disorders, the mechanism by which mitochondrial quality control impacts renal anemia remains elusive. In this study, we showed that FUNDC1, a mitophagy receptor, plays a critical role in EPO-driven erythropoiesis induced by stresses. Mechanistically, EPO production is impaired in REPs in Fundc1-/- mice upon stresses, and the impairment is caused by the accumulation of damaged mitochondria, which consequently leads to the elevation of the reactive oxygen species (ROS) level and triggers inflammatory responses by up-regulating proinflammatory cytokines. These inflammatory factors promote the myofibroblastic transformation of REPs, resulting in the reduction of EPO production. We therefore provide a link between aberrant mitophagy and deficient EPO generation in renal anemia. Our results also suggest that the mitochondrial quality control safeguards REPs under stresses, which may serve as a potential therapeutic strategy for the treatment of renal anemia.

Hydrothermally Stable Ordered Mesoporous Titanosilicates with Highly Active Catalytic Sites

2002 ◽  
Vol 124 (6) ◽  
pp. 888-889 ◽  
Author(s):  
Feng-Shou Xiao ◽  
Yu Han ◽  
Yi Yu ◽  
Xiangju Meng ◽  
Miao Yang ◽  
...  
Keyword(s):  
Highly Active ◽  
Ordered Mesoporous ◽  
Catalytic Sites

Mesoporous CoO-supported palladium nanocatalysts with high performance for o-xylene combustion

2018 ◽  
Vol 8 (3) ◽  
pp. 806-816 ◽  
Author(s):  
Shaohua Xie ◽  
Yuxi Liu ◽  
Jiguang Deng ◽  
Jun Yang ◽  
Xingtian Zhao ◽  
...  
Keyword(s):  
High Performance ◽  
Catalytic Combustion ◽  
Active Oxygen Species ◽  
Catalytic Performance ◽  
Active Oxygen ◽  
Oxygen Species ◽  
Highly Active ◽  
Palladium Nanocatalysts ◽  
Supported Palladium

The adsorbed o-xylene species can immediately react with active oxygen species at the highly active Pd–CoO interface between Pd NPs and meso-CoO, thus resulting in good catalytic performance of Pd/meso-CoO for o-xylene catalytic combustion.

Sign in / Sign up

Export Citation Format

Share Document