Catalysis Science & Technology
·
2025
·
IF 4.2
Yu-Le Wang,Songhai Wu,Yu-Zhen Xu,Yu-Dong Shan,Yong Liu,Xu Han
The selective oxidation of cyclohexene (Cy) to cyclohexene oxide (Cy-ep) using O2 remains challenging due to low epoxidation selectivity. In this work, a series of Mo-doped TS-1 (Mo-TS-1) catalysts were successfully synthesized for the epoxidation of Cy under solvent- and initiator-free conditions with O2 as the oxidant. Among them, 5Mo-TS-1 exhibited high catalytic performance, achieving 43.5% Cy conversion and 50.6% selectivity toward Cy-ep. Additionally, valuable byproducts such as 2-cyclohexen-1-ol (Cy-ol) and 2-cyclohexen-1-one (Cy-one) were obtained with yields of 28.0% and 21.4%, respectively. Since both Cy-ol and Cy-one are valuable intermediates in fragrance synthesis, over 43.5% of Cy was effectively converted into high-value products. Quenching experiments and Raman spectroscopy revealed that surface oxygen vacancies (Ov) facilitate the activation of O2 to form ≡Ov‑superoxo species, which abstract hydrogen from the allylic C-H bond of Cy to generate 3-cyclohexenyl radicals (Cy•). These radicals subsequently react with O2 to form Cy-OO•, followed by hydrogen abstraction from another Cy molecule to yield 2-cyclohexene-1-hydroperoxide (Cy-OOH). A positive correlation between Cy-OOH and Cy-ep formation underscores the critical role of Cy-OOH in the epoxidation process. Furthermore, Raman spectroscopy confirmed the presence of ≡Mo-(η2-O2) peroxo species on the catalyst surface, which preferentially attack the C=C bond of Cy to form Cy-ep. DFT calculations elucidated two distinct O2 activation pathways: In Pathway I, O2 is activated at Ov sites to form ≡Ov‑superoxo, which subsequently reacts with Cy to generate ≡Ov‑peroxo, Cy-OOH, and Cy•. In Pathway II, Mo(V/VI) sites either directly activate O2 or react with peroxo intermediates (≡Ov‑peroxo or Cy-OOH) to form ≡Mo-(η2-O2). This species selectively epoxidizes the alkene bond in Cy to Cy-ep. Notably, the direct activation of O2 at Mo(V/VI) sites bypasses the allylic oxidation route, thereby enhancing the epoxidation selectivity beyond the theoretical limit of 50.0%. This study provides new insight on the importance of surface superoxo and peroxo mediated by Ov and Mo(V/VI) in the epoxidation processes.
研究领域:
催化化学
·
材料化学
·
绿色化学
·
多相催化
·
氧化反应
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2017
·Vol. 27
·期 43
·1700626
·
IF 12.124
Chi Zhang,Wei-Hai Chen,Li-Han Liu,Wen-Xiu Qiu,Wu-Yang Yu,Xian-Zheng Zhang
Conventional photodynamic therapy (PDT) has limited applications in clinical cancer therapy due to the insufficient O 2 supply, inefficient reactive oxygen species (ROS) generation, and low penetration depth of light. In this work, a multifunctional nanoplatform, upconversion nanoparticles (UCNPs)@TiO 2 @MnO 2 core/shell/sheet nanocomposites (UTMs), is designed and constructed to overcome these drawbacks by generating O 2 in situ, amplifying the content of singlet oxygen ( 1 O 2 ) and hydroxyl radical (•OH) via water-splitting, and utilizing 980 nm near-infrared (NIR) light to increase penetration depth. Once UTMs are accumulated at tumor site, intracellular H 2 O 2 is catalyzed by MnO 2 nanosheets to generate O 2 for improving oxygen-dependent PDT. Simultaneously, with the decomposition of MnO 2 nanosheets and 980 nm NIR irradiation, UCNPs can efficiently convert NIR to ultraviolet light to activate TiO 2 and generate toxic ROS for deep tumor therapy. In addition, UCNPs and decomposed Mn 2+ can be used for further upconversion luminescence and magnetic resonance imaging in tumor site. Both in vitro and in vivo experiments demonstrate that this nanoplatform can significantly improve PDT efficiency with tumor imaging capability, which will find great potential in the fight against tumor.
研究领域:
癌症治疗
·
纳米技术
·
生物医学工程
·
光化学
·
成像技术
✓ 已验证
DOI
高影响因子
BIOORGANIC CHEMISTRY
·
2023
·
IF 5.1
Xinxin Liu,Lei Chen,Ze Chen
Photodynamic therapy (PDT) has emerged as a highly efficacious therapeutic modality for malignant tumors owing to its non-invasive property and minimal adverse effects. However, the pervasive hypoxic microenvironment within tumors significantly compromises the efficacy of oxygen-dependent PDT, posing a formidable challenge to the advancement of high-efficiency PDT. Here, we developed a nanostructured photosensitizer (PS) assembled by cationic and anionic zinc phthalocyanines to load oxygen-throttling drug atovaquone (ATO), which was subsequently coated with polydopamine to obtain the final product ATO/ZnPc-CA@DA. ATO/ZnPc-CA@DA exhibited excellent stability, particularly in the blood milieu. Interestingly, the acidic microenvironment can trigger drug release from ATO/ZnPc-CA@DA, leading to a significant enhancement in fluorescence and an augmented generation of reactive oxygen species (ROS). ATO/ZnPc-CA@DA can induce synergistic cytotoxicity of PS and ATO, and significantly enhance the killing ability against tumor cells under hypoxic conditions. The mechanism underlying cytotoxicity of ATO/ZnPc-CA@DA was demonstrated to be associated with augmented cell apoptosis, disruption of mitochondrial membrane potential, diminished ATP production, heightened intracellular ROS generation, and reduced intracellular oxygen consumption. The animal experiments indicated that ATO/ZnPc-CA@DA possessed enhanced tumor targeting capability, along with a reduction in PS distribution within normal organs. Furthermore, ATO/ZnPc-CA@DA exhibited enhanced inhibitory effect on tumor growth and caused aggravated damage to tumor tissue. The construction strategy of nanostructured PS and the synergistic antitumor principle of combined oxygen-throttling drugs can be applied to other PSs, thereby advancing the development of photodynamic antitumor therapy and promoting the clinical translation.
研究领域:
生物医学工程
·
肿瘤学
·
药剂学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF NANOBIOTECHNOLOGY
·
2024
·Vol. 22
·期 1
·1-15
·
IF 10.6
Li Jingchao,Wang Tingting,Shi Yuanfei,Ye Zichen,Zhang Xun,Ming Jiang,Zhang Yafei,Hu Xinyan,Li Yun,Zhang Dongsheng,Xu Qianhe,Yang Jun,Chen Xiaolan,Liu Nian,Su Xinhui
Radionuclides internal radiotherapy (RIT) is a clinically powerful method for cancer treatment, but still poses unsatisfactory therapeutic outcomes due to the hypoxic characteristic of tumor microenvironment (TME). Catalase (CAT) or CAT-like nanomaterials can be used to enzymatically decompose TME endogenous H 2 O 2 to boost TME oxygenation and thus alleviate the hypoxic level within tumors, but their effectiveness is still hindered by the short-lasting of hypoxia relief owing to their poor stability or degradability, thereby failing to match the long therapeutic duration of RIT. Herein, we proposed an innovative strategy of using facet-dependent CAT-like Pd-based two-dimensional (2D) nanoplatforms to continuously enhance RIT. Specifically, rationally designed 2D Pd@Au nanosheets (NSs) enable consistent enzymatic conversion of endogenous H 2 O 2 into O 2 to overcome hypoxia-induced RIT resistance. Furthermore, partially coated Au layer afford NIR-II responsiveness and moderate photothermal treatment that augmenting their enzymatic functionality. This approach with dual-effect paves the way for reshaping TME and consequently facilitating the brachytherapy ablation of cancer. Our work offers a significant advancement in the integration of catalytic nanomedicine and nuclear medicine, with the overarching goal of amplifying the clinical benefits of RIT-treated patients. Graphical abstract
研究领域:
肿瘤学
·
纳米医学
·
核医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nano Research
·
2023
·Vol. 16
·期 5
·6278-6289
·
IF 9.9
Xu Jialun,Zhang Zhihua,Yu Daiyi,Du Wei,Song Nan,Duan Xuezhi,Zhou Xinggui
The catalytic performances over propylene epoxidation with H 2 and O 2 (HOPO process) are significantly affected by the properties (e.g., surface properties, Ti coordination, and morphology) of titanosilicate zeolite. Introducing urea into zeolite synthesis is a simple and convenient method to modify these properties of titanosilicate zeolite. Uncalcined pore-blocked titanium silicalite-1 (TS-1, i.e., TS-1-B) with the lower urea dosage possesses more defective structure and unsaturated coordinated Ti sites verified by 29 Si nuclear magnetic resonance (NMR) and X-ray photoelectron spectroscopy (XPS) analysis, which results in a high initial activity and hydrogen efficiency; while the high surface acidity generated by these Ti species leads to a continuous decrease in the activity and the propylene oxide (PO) selectivity during the reaction. As the amount of urea gradually increases, the TS-1-B samples present the reduced surface defects and defective and unsaturated Ti species. Specially, TS-1-B-0.30U presents the weaker PO adsorption on PO-diffusion reflectance infrared Fourier transform spectra (DRIFTS), and thus results in the high stable PO formation rate and selectivity over its Au catalyst. Furthermore, a flat-plate-like shape with a shorter thickness of 100 nm along the b-axis direction is observed on the urea-modified TS-1. Compared with the conventional ellipsoidal TS-1 with crystal sizes of 200 and 500 nm, the flat-plate-like TS-1-0.30U displays the less surface defects, unsaturated Ti species, and the weaker Lewis acid, which is favorable for the desorption and intracrystalline diffusion of PO, thus reduces the occurrence of side reactions for the improved selectivity and stability. This work may provide a reference for developing titanium-containing materials with high activity and stability over HOPO reaction.
✓ 已验证
产品关联
DOI
高影响因子
ACS Earth and Space Chemistry
·
2023
·
IF 3.4
Hao Tian,Xue-Bin Zhang,Yin-Ping Li,Qing He,Na-Na Tian,Song-Hai Wu,Xu Han
Although inorganic Fe(IV)═O oxo and Fe(III)-OOH peroxo have attracted more attention in aqueous environments, direct evidence for the characterization and identification of those oxidizing species is still lacking. In this study, the doped Cu/Co increases the reactivity of ferrihydrite/hematite in oxidizing As(III) by S(IV)-O2 under alkaline and dark conditions. Quenching experiments exclude the contributions of ·OH, O2•–, SO3•–, SO4•–, SO5•–, HSO5–, and H2O2 and confirm that peroxo and oxo are primary oxidizing species in As(III) oxidation. Electrochemical analyses indicate that Fe(IV)═O oxo and Fe(III)-OOH peroxo are primarily located on the surface of ferrihydrite and hematite. Selective oxidation of methyl phenyl sulfoxide and methyl phenyl sulfide to the corresponding oxidation products further reveals the presence of ≡Fe(IV)═O oxo on both ferrihydrite and hematite, and the doped Cu/Co significantly decreases the produced ≡Fe(IV)═O oxo on ferrihydrite, while increases the produced ≡Fe(IV)═O oxo on hematite. Meanwhile, selective oxidation of benzyl alcohol to benzaldehyde indicates the presence of ≡Fe(III)-OOH peroxo on both ferrihydrite and hematite, and the doped Cu/Co apparently increases the produced ≡Fe(III)-OOH peroxo on ferrihydrite and hematite. Raman analysis further reveals the presence of ≡Fe(IV)═O oxo and ≡Fe(III)-OOH peroxo on pure and metal-doped ferrihydrite/hematite, which also confirms that the doped Cu/Co decreases the produced ≡Fe(IV)═O oxo on ferrihydrite and increases ≡Fe(IV)═O oxo on hematite, while apparently increasing ≡Fe(III)-OOH peroxo on both ferrihydrite and hematite. This study enriches our understanding on the oxidizing species in the S(IV)-mediated oxidation processes under alkaline conditions, providing new insight on the oxidation reactivity of surface peroxo and oxo species mediated by the doped metal ions.
✓ 已验证
产品关联
DOI
高影响因子
Acta Biomaterialia
·
2022
·
IF 10.633
Furong Liu,Tao He,Songlin Gong,Meiling Shen,Shuang Ma,Xianzhou Huang,Lu Li,Li Wang,Qinjie Wu,Changyang Gong
Combining the internal force-driven chemodynamic therapy (CDT) and the external energy-triggered photodynamic therapy (PDT) holds great promise to achieve an advanced anticancer effect based on reactive oxygen species (ROS). However, the insufficient oxy-substrates supply in tumor microenvironment, like hydrogen peroxide (H 2 O 2 ) and oxygen (O 2 ), is the Achilles heel that greatly restricts the efficacy of this ROS-based treatment. Herein, the construction of a c opper p e roxide-based tumor pH-re s ponsive a utocatalytic nano r eactor (CESAR), via an albumin-mediated biomimetic mineralization strategy is described. The decoration of human serum albumin endows the nanoreactor good hydrophilicity and biocompatibility, which is highly desired for the metal-based materials. Upon exposure to acidic tumor microenvironment, CESAR presents a pH-triggered disintegration with Cu 2+ , H 2 O 2 and O 2 generated instantly. The generated H 2 O 2 complements the hyperoxide deficiency and initiates a localized Fenton-like reaction with the assistance of Cu 2+ for highly toxic hydroxyl radicals (•OH) production for improving CDT. The evolved O 2 gas enables hypoxia relief for enhanced Ce6-mediated PDT. This H 2 O 2 /O 2 self-supplying strategy significantly amplifies the tumor oxidative damage and gains an optimal treatment outcome, which offers a new paradigm for optimizing the tumor therapeutic options limited by oxide or hyperoxide deficiency, not only for CDT/PDT, but also other oxy-substrates involved strategies. Statement of significance The shortage of oxy-substrates in the tumor microenvironment remains a great challenge for ROS-based cancer therapy. Herein, we introduce human serum albumin as a scaffold to stabilize copper peroxide nanomaterials for constant production of H 2 O 2 and O 2 to enhance chemodynamic/photodynamic therapy. The tumor pH-triggered H 2 O 2 /O 2 production and Cu 2+ release are confirmed, assuring the strategy of a highly precise, effective way to destroy tumor without any side effects. This work lends new and exciting insights into the engineering design of autocatalytic oxy-substrates self-supply nanoreactor for overcoming the bottlenecks, like the oxy-substrates deficiency of CDT/PDT and the poor stability of metal peroxides, to achieve highly effective chemodynamic/photodynamic therapy.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Carbon Energy
·
2023
·
IF 20.5
Feiyang Yang,Ying Yao,Yunkai Xu,Cong Wang,Meiling Wang,Jingjie Ren,Cunzhong Zhang,Feng Wu,Jun Lu
Although biomass-derived carbon (biochar) has been widely used in the energy field, the relation between the carbonization condition and the physical/chemical property of the product remains elusive. Here, we revealed the carbonization condition's effect on the morphology, surface property, and electrochemical performance of the obtained carbon. An open slit pore structure with shower-puff-like nanoparticles can be obtained by finely tuning the carbonization temperature, and its unique pore structure and surface properties enable the Li–O 2 battery with cycling longevity (221 cycles with 99.8% Coulombic efficiency at 0.2 mA cm −2 and controlled discharge–charge depths of 500 mAh g −1 ) and high capacity (16,334 mAh g −1 at 0.02 mA cm −2 ). This work provides a greater understanding of the mechanism of the biochar carbonization procedure under various pyrolysis conditions, paving the way for future study of energy storage devices.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2026
·
IF 6
Chaosi Liu,Yijing Gao,Yixiang Niu,Yumei Zhang,Cheng Wang,Tengda Li,Chunhui Xu,Weidong Zhu,Xinqing Lu
Develop Pd-based catalysts for propylene epoxidation with H 2 and O 2. • Sn species in PdSn/Ti-MWW increase the electron density of Pd. • Increased electron density of Pd enhances the H 2 utilization. • Sn significantly promotes the catalytic propylene epoxidation. The low-temperature epoxidation of propylene with H 2 and O 2 to propylene oxide (PO), commonly referred to as the low-temperature HOPO process, over titanosilicate zeolite-supported Pd catalysts is economically attractive and environmentally friendly. However, PO selectivity remains a major challenge for these systems and is comparatively low, because this process is commonly accompanied with propylene hydrogenation to propane. In the present study, a novel and efficient Ti-MWW-supported PdSn catalyst (PdSn/Ti-MWW) was developed for this low-temperature HOPO process, displaying a substantially high PO selectivity. The results on extensive characterizations, in combination with Density Functional Theory (DFT) calculations, for PdSn/Ti-MWW and Pd/Ti-MWW verify that the introduction of Sn species into Pd/Ti-MWW can boost the electron density of Pd species while does not affect the coordination states of Ti species and the textural properties of the zeolite. Interestingly, the enhanced Pd electron density will weaken the adsorption of propylene on the Pd active sites, resulting in inhibiting propylene hydrogenation, which is beneficial for the selective production of PO. Catalytic tests reveal that the optimal 0.33Pd0.22Sn/Ti-MWW catalyst achieves a PO selectivity of 68.4 % and a maximum PO productivity of 7.5 mol g Pd -1 h −1 , far exceeding monometallic Pd/Ti-MWW, while the undesired propane selectivity drops sharply. Moreover, PdSn/Ti-MWW shows an excellent stability and reusability as key catalytic traits. Thus, this work establishes an effective electronic modulation strategy for designing high-performance bimetallic Pd catalysts, and lays solid experimental and theoretical foundations for the industrial application of sustainable low-temperature HOPO technology. Download: Download high-res image (81KB) Download: Download full-size image
✓ 已验证
产品关联
DOI
高影响因子
ChemSusChem
·
2023
·
IF 8.4
Juanjuan Han,Yangyang Zhang,Xiumeng Zheng,Yuyang Lu,Wanting Li,Xiaorong Zhou,Zhandong Ren,Yi Liu,Meixue Hu,Li Xiao,Lin Zhuang
Graphical A novel AEM with good strength and flexibility was synthesized by combining rigid PPO and flexible PVA. Dual cationic groups were added to improve ion concentration and create ion channels, enhancing ion conductivity. Cross-linking and phase separation improved the AEM's resistance to alkali. A series of cross-linked AEMs ( c -DQPPO/PVA) are synthesized by using rigid polyphenylene oxide and flexible poly(vinyl alcohol) as the backbones. Dual cations are grafted on the PPO backbone to improve the ion exchange capacity (IEC), while glutaraldehyde is introduced to enhance compatibility and reduce swelling ratio of AEMs. In addition to the enhanced mechanical properties resulting from the rigid-flexible cross-linked network, c -DQPPO/PVA AEMs also exhibit impressive ionic conductivity, which can be attributed to their high IEC, good hydrophilicity of PVA, and well-defined micro-morphology. Additionally, due to confined dimension behavior and ordered micro-morphology, c -DQPPO/PVA AEMs demonstrate excellent chemical stability. Specifically, c -DQPPO/PVA-7.5 exhibits a wet-state tensile strength of 12.5 MPa and an elongation at break of 53.0 % at 25 °C. Its OH − conductivity and swelling degree at 80 °C are measured to be 125.7 mS cm −1 and 8.2 %, respectively, with an IEC of 3.05 mmol g −1 . After 30 days in a 1 M NaOH solution at 80 °C, c -DQPPO/PVA-7.5 experiences degradation rates of 12.8 % for tensile strength, 27.4 % for elongation at break, 14.7 % for IEC, and 19.2 % for ion conductivity. With its excellent properties, c -DQPPO/PVA-7.5 exhibits a peak power density of 0.751 W cm −2 at 60 °C in an H 2 -O 2 fuel cell.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INORGANIC CHEMISTRY COMMUNICATIONS
·
2021
·
IF 2.495
Qian-Qian Huang
A novel tetranuclear nickel(II)-flavonolate complex [Ni II 4 (fla) 4 (CH 3 O) 4 (H 2 O) 4 ] (flaH: 3-Hydroxyflavone, flavonol) was synthesized. Its crystal structure and spectroscopic features have been investigated in details by physicochemical methods and single crystal X-ray diffraction. Different from other mononuclear metal-flavonolate complexes, this complex demonstrates a cluster molecular structure which has four Ni II centers, and each Ni II centre is coordinated by a bidentate flavonolate, three methanol and a water molecule. The crystal of this complex is tetragonal crystal system: space group I 41/a, a = 24.4361(14), b = 24.4361(14), c = 12.7972 (14), α = β = γ = 90 ° , V = 7641.5 (12), Z = 4. The complex can react with O 2 , in other words, it has enzymatic reactivity just like enzyme-substrate model of quercetin 2,3-dioxygenase, and the reaction products are similar with the other reported enzyme-substrate models.
✓ 已验证
产品关联
DOI
高影响因子
Advanced Materials Interfaces
·
2018
·Vol. 5
·期 22
·1801070
·
IF 4.834
Lin Fan,Doudou Lou,Haoan Wu,Xizhi Zhang,Yefei Zhu,Ning Gu,Yu Zhang
In spite of the competitive advantages, inorganic nanoparticle mimic enzymes exhibit inherent disadvantages of limited catalytic efficiency and lacking selectivity. Here, a gold nanoparticle (AuNP)-based mimic enzyme with significantly enhanced glucose selectivity and catalytic activity is constructed and demonstrated for the first time. Aminophenylboronic acid is employed to increase the affinity to glucose, as well as build molecular imprinted polymer shells to realize the selectivity for template molecules of glucose. Besides that, heptadecafluoro- n -octyl bromide nanoemulsion with the function of providing oxygen is introduced to gain a further improvement in catalytic activity, which successfully enhances the catalytic efficiency ( k cat / K m ) up to about 270-fold. Based on the demonstrated catalytic properties, AuNP-based glucose oxidase mimics are successfully applied in practical glucose detection of drinks and blood glucose.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）