Materials
·
2025
·Vol. 18
·期 8
·1874
·
IF 3.2
Chao Wu,Haoyan Zhang,Xuan Zheng,Jing Ding,Yuanyuan Li,Feiyong Chen,Zhengfeng Zhao
The urgency of reducing pollution and developing clean energy storage requires efficient photocatalytic hydrogen evolution (PHE) tactics. To improve solar conversion efficiency, it is highly imperative to accelerate the photocarriers separation and transport through materials design. A stable hydrogen evolution photocatalyst based on TpPa-COFs (triformylphloroglucinol phenylenediamine covalent organic frameworks) was developed by a molecular-level design strategy. The study successfully introduced a molecular-scale Ir active site onto the surface of TpPa-COFs via coordination bonds. It verified the structural integrity of TpPa-COFs and the existence of Ir through the basic structural characterizations, such as Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). After the Ir-based coordination compound joining, the absorption edge of TpPa-COF-M1 and TpPa-COF-M2 was extended to 750 nm. The TpPa-COF + M1 exhibited the highest photocatalytic H2evolution rate of 662 µmol/h (10 mg catalyst) under visible-light (λ ≥ 420 nm) irradiation. The apparent quantum yield (AQY) of TpPa-COF-M1 is calculated to be 1.9%, 3.8%, 4.8%, 2.8%, 1.8%, and 0.3% at monochromatic wavelengths of 420, 450, 470, 500, 550, and 600 nm, respectively. Our findings confirm that the molecular-level design of photocatalysts can effectively boost performance and reduce cost in photocatalytic reactions and provide an important strategy for designing efficient photocatalysts.
研究领域:
材料科学
·
能源化学
·
光催化
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RUSSIAN JOURNAL OF GENERAL CHEMISTRY
·
2016
·Vol. 86
·期 7
·1747-1752
·
IF 0.481
Lin Meijuan,Tang Qiang,Zeng Huijuan,Xing Guang,Ling Qidan
Several new Ir(III) complexes with 2-(4-bromophenyl)-1 H -benzo[d]imidazole or 2-(4-bromophenyl)- 1-methyl-benzo[ d ]imidazole ligands as cylcometalated ligand and acetylacetonate or picolinate as the ancillary ligand were synthesized and their structures and photophysical properties were characterized. HOMO and LUMO energy levels and the molecular structures of Ir(III) complexes were scrutinized by DFT calculations. The complexes exhibited green luminescence at the maximum emission peaks at ca 495–522 nm. The methyl group substituent and replacing of acetylacetonate with picolinate complex can enhance the complex thermal stability. HOMO energy levels of the complexes vary from –4.99 to –5.44 eV, the LUMO energy levels are between –1.52 and –1.97 eV.
研究领域:
材料科学
·
化学
✓ 已验证
DOI
高影响因子
Journal of Biophotonics
·
2021
·Vol. 14
·期 11
·e202100117
·
IF 3.207
Lijun Zhu,Jianjun Chen,Ting Yan,Gulinigaer Alimu,Xueliang Zhang,Shuang Chen,Mutalifu Aimaiti,Rong Ma,Nuernisha Alifu
Photothermal therapy (PTT) has attracted wide attention due to its noninvasiveness and its thermal ablation ability. As photothermal agents are crucial factor in PTT, those with the characteristics of biocompatibility, non-toxicity and high photothermal stability have attracted great interest. In this work, new indocyanine green (IR-820) was utilized as a photothermal agent and near-infrared (NIR) fluorescence imaging nanoprobe. To improve the biocompatibility, poly(styrene-co-maleic anhydride) (PSMA) was utilized to encapsulate the IR-820 molecules to form novel IR-820@PSMA nanoparticles (NPs). Then, the optical and thermal properties of IR-820@PSMA NPs were studied in detail. The IR-820@PSMA NPs showed excellent photothermal stability and biocompatibility. The cellular uptaking ability of the IR-820@PSMA NPs was further confirmed in HeLa cells by the NIR fluorescent confocal microscopic imaging technique. The IR-820@PSMA NPs assisted PTT of living HeLa cells was conducted under 793 nm laser excitation, and a high PTT efficiency of 73.3% was obtained.
研究领域:
生物医学工程
·
肿瘤学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2019
·
IF 4.507
Lele Jin,Wenzhi Li,Qiying Liu,Longlong Ma,Song Li,Yang Liu,Baikai Zhang,Qi Zhang
The liquid fuel (made of C 5 /C 6 alkanes) was obtained directly from the hydrogenolysis of microcrystalline cellulose (MCC) with Ir-VO x /SiO 2 combined with HZSM-5 as the composite catalyst in a biphasic system (n-dodecane + H 2 O). The performance of the catalyst was investigated by carrying out a series of experiments using various V/Ir molar ratios , catalyst dosages, reaction temperatures, reaction time, hydrogen pressure and substrates. At the optimized conditions, the cellulose was almost completely converted, and at the same time, a high C 5 /C 6 yield of 85.1% was obtained at 210 °C for 24 h and 6 MPa with the V/Ir molar ratio being 0.13. These results not only proved that Ir-VO x /SiO 2 (V/Ir = 0.13) has excellent performance for the hydrogenolysis of MCC to liquid alkanes, but also indicated that vanadium is a good metal promoter for iridium . In addition, it was proven the C5/C6 alkanes were obtained via sorbitol through the combined effect of Ir-VO x /SiO 2 and HZSM-5.
研究领域:
催化化学
·
可再生资源转化
✓ 已验证
产品关联
DOI
高影响因子
Advances in Natural Sciences-Nanoscience and Nanotechnology
·
2024
·Vol. 15
·期 1
·015008
·
IF 1.7
Tai Thien Huynh,Quyen Huynh,Ngoc-Han T Huynh,Hau Quoc Pham
In this work, we prepared an Ir,N-doped TiO2 nanomaterial via a facile HNO3-assisted hydrothermal process that was used as an advanced support for nano-sized Pt nanoparticles (NPs) for the formic acid oxidation reaction (FAOR). The physical and electrochemical behaviours of the as-made Pt/Ir,N-doped TiO2 catalyst were systemically investigated through X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), field emission scanning electron microscopes coupled with energy dispersive X-ray analysis (FE-SEM/EDX mapping), transmission electron microscopy (TEM), linear sweep voltammetry (LSV), Tafel slope, CO-stripping, and chronoamperometric (CA) test. The Pt NPs (ca. 3 nm) were anchored on the Ir,N-doped TiO2 support, being formed by a mixture of rutile and brookite with a particle size of several ten nanometers. Due to the small size and uniform distribution of Pt NPs, the Pt/Ir,N-doped TiO2 catalyst had an electrochemical surface area of 79.88 m2 g−1, which was greater than that of the commercial Pt/C (77.63 m2 g−1). In terms of the FAOR, the Pt/Ir,N-doped TiO2 catalyst showed a negative FAOR onset potential, high current density (11.85 mA cm−2), and superior CO-tolerance compared to the commercially available catalyst. Also, the as-made catalyst possessed high electrochemical durability after 3600 s for testing. The enhanced FAOR efficiency was assigned to the formation of a dual-doping effect and strong interplay between Pt and TiO2-based support, which not only improved the electron transfer but also weakened the adsorption of carbonaceous species, thereby boosting the reaction kinetics. This study could open up a facile but effective strategy to promote particular electrochemical applications.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2023
·Vol. 14
·期 1
·1-13
·
IF 16.6
Chen Shiyi,Zhang Shishi,Guo Lei,Pan Lun,Shi Chengxiang,Zhang Xiangwen,Huang Zhen-Feng,Yang Guidong,Zou Ji-Jun
Surface reconstruction generates real active species in electrochemical conditions; rational regulating reconstruction in a targeted manner is the key for constructing highly active catalyst. Herein, we use the high-valence Mo modulated orthorhombic Pr 3 Ir 1− x Mo x O 7 as model to activate lattice oxygen and cations, achieving directional and accelerated surface reconstruction to produce self-terminated Ir‒O bri ‒Mo (O bri represents the bridge oxygen) active species that is highly active for acidic water oxidation. The doped Mo not only contributes to accelerated surface reconstruction due to optimized Ir‒O covalency and more prone dissolution of Pr, but also affords the improved durability resulted from Mo-buffered charge compensation, thereby preventing fierce Ir dissolution and excessive lattice oxygen loss. As such, Ir‒O bri ‒Mo species could be directionally generated, in which the strong Brønsted acidity of O bri induced by remaining Mo assists with the facilitated deprotonation of oxo intermediates, following bridging-oxygen-assisted deprotonation pathway. Consequently, the optimal catalyst exhibits the best activity with an overpotential of 259 mV to reach 10 mA cm geo −2 , 50 mV lower than undoped counterpart, and shows improved stability for over 200 h. This work provides a strategy of directional surface reconstruction to constructing strong Brønsted acid sites in IrO x species, demonstrating the perspective of targeted electrocatalyst fabrication under in situ realistic reaction conditions.
研究领域:
电化学
·
材料科学
✓ 已验证
DOI
高影响因子
BIOMATERIALS
·
2014
·
IF 8.312
Yang Wang,Tao Liu,Erlong Zhang,Shenglin Luo,Xu Tan,Chunmeng Shi
Personalized oncology significantly relies on the development of theranostic agents to integrate cancer therapeutics and diagnostics. Current strategy for development of such multifunctional agents requires multistep chemical conjugation with cancer specific ligands, contrast agents and therapeutic drugs. In this study, we reported a near infrared (NIR) heptamethine indocyanine dye, IR-780, which selectively accumulated in the mitochondria of drug-resistant human lung cancer cells (A549/DR) and significantly inhibited cell growth, self-renewal and migration without the need of any chemical conjugation. IR-780 was also able to induce A549/DR cell apoptosis by disrupting the mitochondrial function. Furthermore, IR-780 dye exhibited remarkable tumoricidal activity and inhibited tumor recurrence in mouse syngeneic Lewis lung carcinoma xenograft model. With the unique properties of targeting, near infrared imaging and inhibitive effect to the drug-resistant cancer cells both in vitro and in vivo, IR-780 may represent a potential theranostic agent for tumor recurrence.
研究领域:
肿瘤学
·
药理学
·
细胞生物学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF CATALYSIS
·
2024
·
IF 6.5
Ruoyuan Li,Aixia Li,Junhua Li,Yao Wang,Zhiming Liu
Selective catalytic reduction of NO x by CO (CO-SCR) in the presence of O 2 is challenging because in this process CO is prone to being oxidized by O 2 , thus inhibiting NO x reduction by CO. Furthermore, SO 2 typically leads to the deactivation of the CO-SCR catalyst. Herein, a significant promoting effect of SO 2 on Ir/SiO 2 catalyst for the CO-SCR of NO x in the presence of O 2 is reported. In-situ X-ray Absorption Fine Structure (XAFS) and X-ray photoelectron spectroscopy (XPS) analysis showed that SO 2 does not affect the chemical nature of Ir 0 under reaction conditions. However, SO 2 can be oxidized to sulfate and deposit on the catalyst surface. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) analysis demonstrated that the presence of SO 2 can inhibit the CO + O 2 reaction, thus leaving more CO available to reduce NO x over the active Ir 0 sites. As a result, the reduction of NO x is remarkably promoted even in the presence of O 2 and SO 2 .
研究领域:
催化化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
RENEWABLE ENERGY
·
2023
·
IF 8.7
Yun Zhang,Chuanbiao Zhang,Wenjuan Li,Qiuping Xiao,Fengyuan Jiao,Sen Xu,Yanhua Lan,Yizheng Fu,Chi-Min Shu,Weiguo Cao
Stearic acid provides a basis for developing renewable energy, such as solar energy and biomass energy. A thermogravimetric-infrared spectroscopy (TG-IR) experimental test is conducted to obtain the thermal decomposition progress and the main gaseous products of stearic acid. The result shows that small gaseous products (H 2 O, CO 2 , CO, alkanes, olefins , etc.) are released. Furthermore, the method of reactive molecular dynamics simulation (ReaxFF-MD) is utilized to look into the pyrolysis reaction mechanism of stearic acid. The main pyrolysis products of stearic acid received by ReaxFF-MD are C 2 H 4 , H 2 , C 2 H 2 , CH 4 , H 2 O, CO 2 , and CO, consisting of the result of the TG-IR test. The effect of the simulated system density and temperature on the distribution of main products is also explored. Also, the thermal kinetic analysis is conducted by the initial consumption of stearic acid under different temperatures. The primary reaction mechanism of stearic acid pyrolysis is that the stearic acid molecules dissociate through C–C bonds break to generate C 2 H 4 , CH 4 , C 2 H 2 , C 3 H 6 , and other small molecules and radicals, and a typical reaction mechanism scheme of stearic acid pyrolysis is presented. The results provide a reference for explaining the macroscopic explosion characteristics of dust at the microscopic mechanism level.
研究领域:
化学工程
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
Theranostics
·
2019
·
IF 8.063
Zhe Feng,Xiaoming Yu,Minxiao Jiang,Liang Zhu,Yi Zhang,Wei Yang,Wang Xi,Gonghui Li,Jun Qian
Rationale: Cerebrovascular diseases, together with malignancies, still pose a huge threat to human health nowadays. With the advantages of its high spatial resolution and large penetration depth, fluorescence bioimaging in the second near-infrared spectral region (NIR-II, 900-1700 nm) and its related imaging-guided therapy based on biocompatible fluorescence dyes have become a promising theranostics method. Methods: The biocompatibility of IR-820 we used in NIR-II fluorescence bioimaging was verified by long-term observation. The model of the mouse with a cranial window, the mouse model of middle cerebral artery occlusion (MCAO) and a subcutaneous xenograft mouse model of bladder tumor were established. NIR-II fluorescence cerebrovascular functional imaging was carried out by IR-820 assisted NIR-II fluorescence microscopy. Bladder tumor was treated by NIR-II fluorescence imaging-guided photothermal therapy. Results: We have found that IR-820 has considerable NIR-II fluorescence intensity, and shows increased brightness in serum than in water. Herein, we achieved real time and in vivo cerebrovascular functional imaging of mice with high spatial resolution and large penetration depth, based on IR-820 assisted NIR-II fluorescence microscopy. In addition, IR-820 was successfully employed for NIR-II fluorescence imaging and photothermal therapy of tumor in vivo , and the subcutaneous tumors were inhibited obviously or eradicated completely. Conclusion: Due to the considerable fluorescence intensity in NIR-II spectral region and the good photothermal effect, biocompatible and excretable IR-820 holds great potentials for functional angiography and cancer theranostics in clinical practice.
研究领域:
生物医学工程
·
神经科学
·
肿瘤学
✓ 已验证
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Hong Ming An,Zhi Liang Zhao,Lian Ying Zhang,Yue Chen,Yan Yan Chang,Chang Ming Li
Ternary metal-element alloys have been reported as efficient electrocatalysts toward various electrochemical reactions, but a unique three-dimensional (3D) Ir-alloyed ternary nanosheet-composed flower (NCF) structure has not been explored yet. Herein, an innovated 1.8 nm Ir-alloyed ultrathin ternary PdIrCu NCF structure is synthesized via one-pot solvothermal reduction without using any surfactant. The as-prepared PdIrCu/C NCF catalyst remarkably improves the stability than commercial Pd/C toward formic acid electrooxidation while resulting in significantly increased mass activity. The improvement of electrocatalytic properties depends on the introduction of Ir and Cu atoms, which greatly prevented poisoning from CO while modifying the electronic structure of Pd for increased reaction active sites and accelerated charge-transfer rate as well as facilitated mass transport by ultrathin NCF 3D structure. Therefore, this catalyst possesses a promising application prospect in electrochemical energy storage/conversion systems.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nature Communications
·
2023
·Vol. 14
·期 1
·1-10
·
IF 16.6
Li Yanxun,Huang Bo,Zhang Xuning,Ding Jianwei,Zhang Yingyu,Xiao Linge,Wang Boxin,Cheng Qian,Huang Gaosheng,Zhang Hong,Yang Yingguo,Qi Xiaoying,Zheng Qiang,Zhang Yuan,Qiu Xiaohui,Liang Minghui,Zhou Huiqiong
The stability of organic solar cells is a key issue to promote practical applications. Herein, we demonstrate that the device performance of organic solar cells is enhanced by an Ir/IrO x electron-transporting layer, benefiting from its suitable work function and heterogeneous distribution of surface energy in nanoscale. Notably, the champion Ir/IrO x -based devices exhibit superior stabilities under shelf storing ( T 80 = 56696 h), thermal aging ( T 70 = 13920 h), and maximum power point tracking ( T 80 = 1058 h), compared to the ZnO-based devices. It can be attributed to the stable morphology of photoactive layer resulting from the optimized molecular distribution of the donor and acceptor and the absence of photocatalysis in the Ir/IrO x -based devices, which helps to maintain the improved charge extraction and inhibited charge recombination in the aged devices. This work provides a reliable and efficient electron-transporting material toward stable organic solar cells.
研究领域:
材料科学
·
能源技术
·
物理化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子