Catalysis Science & Technology
·
2020
·Vol. 10
·期 23
·8026-8033
·
IF 5.721
Qiu-Jin Wu,Min-Jie Mao,Jian-Xin Chen,Yuan-Biao Huang,Rong Cao
The design and preparation of porous catalysts with multiple catalytically active sites for synergistically catalytic conversion of CO2 still remains a challenge. Herein, cobalt porphyrin as a Lewis acidic active site was introduced in imidazolium-functionalized cationic covalent triazine frameworks (denoted as Co-PCCTFs) via copolymerization of cobalt 5,10,15,20-tetrakis(4-cyanophenyl)porphyrin (Co-TPPCN) and 1,3-bis(4-cyanophenyl) imidazolium chloride ([BCIM]Cl). The obtained bifunctional Co-PCCTFs with positively charged imidazolium groups have high BET surface areas and show sufficient CO2 adsorption uptakes. The nucleophilic halide anions of the imidazolium parts and the cobalt porphyrin Lewis acid sites were positioned in close proximity so that the Co-PCCTFs could synergistically activate substrates and intermediates. Compared with ICTF-400 free of Co2+ that was obtained from [BCIM]Cl, Co-PCCTF5 exhibited enhanced activity for the cycloaddition of CO2 to epoxides to produce cyclic carbonates without a cocatalyst under mild conditions. Moreover, Co-PCCTF5 is sufficiently stable so that it could be reused more than 5 times without loss of catalytic activity. This work provides a new approach for the design and preparation of efficient multifunctional catalysts with multiple sites for synergistic catalysis.
研究领域:
化学工程
·
材料科学
·
催化
·
环境化学
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
·
2018
·
IF 0
Shanshan Jie,Congqiang Yang,Yuan Chen,Zhigang Liu
The highly dispersed active sites are desirable to optimize the atom efficiency. In this study, a series of novel cobalt grafted in N-doped carbon (Co-N-C) catalysts for selective oxidation of ethylbenzene are synthesized by heating a solution of cobalt porphyrin and peptides in ionic liquids, which are also characterized by techniques such as FT-IR, XRD, SEM-EDX, HR-TEM, and XPS. The results show that the as-prepared catalysts have an attractive catalytic performance, namely, 40% of ethylbenzene conversion and 75% of selectivity to acetophenone. Especially, the activity and selectivity of the as-prepared catalysts remain almost similar even after the 10th run. Moreover, the modified-complexometry method is verified to improve the dispersion of metal active sites. The remarkable catalytic performance of the as-prepared catalysts is attributed to the highly dispersed active sites and strong interactions between Co and N species in Co-N x moieties.
研究领域:
催化
·
材料科学
·
化学工程
·
分析化学
✓ 已验证
产品关联
DOI
JOURNAL OF MOLECULAR STRUCTURE
·
2025
·
IF 4.7
Faliang Gou,Wenwen Jiang,Linjun Shao,Xu Jiang,Huanwang Jing
Five N -heterocyclic-modified cobaltoporphyrins were designed and synthesized as bifunctional homogeneous catalysts. They have demonstrated high efficiency in catalyzing the cycloaddition of epoxides and CO 2 to produce cyclic carbonates without a cocatalyst. The nucleophilicity of N -heterocyclic modification groups on metalloporphyrin ligands was found to directly impact their catalytic performance. Under the optimal conditions, catalyst J- o 4B exhibited the best catalytic performance with 99.9% PO conversion and >99% selectivity, while demonstrating notable substrate generality. A preliminary investigation into the kinetic behavior of the cycloaddition between epichlorohydrin (ECH) and CO 2 was carried out, employing three distinct N -heterocyclic-modified cobaltoporphyrins J- o 4B, J- o 4P and J- o 4T . The apparent activation energies of the cycloaddition reaction in the presence of various catalyst were subsequently determined. Moreover, the catalyst structure and experimental results were scrutinized to validate the proposed tri-synergistic catalytic mechanism for the cycloaddition of epoxides and CO 2 catalyzed by the N -heterocyclic-modified cobaltoporphyrins.
研究领域:
有机化学
·
无机化学
·
催化化学
·
材料科学
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Lu Zhao,Aiai Wang,Yaru Li,Yunfeng Bai,Feng Feng
Reactive oxygen species (ROS)-mediated therapy utilizes the slightly acidic environment of tumor microenvironment and the high amount of H 2 O 2 to disrupt the redox balance of tumor cell while minimizing damage to normal cell. However, this strategy was greatly compromised by the powerful antioxidant capacity of tumors and the limited ROS generation rate of bimetallic metal-organic frameworks (BMOFs). In pursuit of innovative strategies for precise diagnosis and effective treatment, a smart nanotheranostics Zr-TCPP(Co)/ICG/PEG/Apt-M (ZTCIPA) based on Zr/Co porphyrin MOFs was designed. Under 808 nm laser irradiation, ZTCIPA demonstrated exceptional photothermal conversion efficiency alongside robust singlet oxygen ( 1 O 2 ) generation, ensuring potent tumor ablation. Meanwhile, the temperature elevation significantly accelerated the Co 2+ mediated catalytic decomposition of H 2 O 2 to generate •OH. Large amounts of •OH and 1 O 2 formed ROS storm effectively damaged mitochondria and further resulted in tumor cell death. Furthermore, ZTCIPA achieved tumor targeted specificity while enabling real-time fluorescence imaging (FLI)/photothermal imaging (PTI) for accurate tracking. The results in vitro and in vivo demonstrated that ZTCIPA could effectively inhibit tumor growth by photothermal amplified ROS storm under 808 nm laser irradiation. Thus, this novel strategy has enormous potential by solving the bottleneck of ROS-mediated therapies.
研究领域:
纳米医学
·
肿瘤学
·
材料科学
·
诊疗一体化
·
生物成像
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
·
IF 8.128
Qingxiang Xu,Long Zhao,Yuhan Ma,Rui Yuan,Maosong Liu,Zhaoli Xue,Henan Li,Jianming Zhang,Xinping Qiu
Charge states at the catalytic interface can intensely alter the charge transfer mechanism and thus the oxygen reduction performance. Two symmetric cobalt porphyrins with electron deficient 2,1,3-benzothiadiazole (BTD) and electron-donating propeller-like triphenylamine (TPA) derivatives have been designed firstly, to rationally generate intramolecular partial charges, and secondly, to utilize the more exposed molecular orbitals on TPA for enhancing the charge transfer kinetics. The catalytic performance of the two electrocatalysts was examined for oxygen reduction reactions (ORR) in acidic electrolyte. It was found that BCP1/C with two BTD groups showed greater reduction potential but less limiting current density as compared to BCP2/C bearing BTD-TPA units. The reduced potential of BCP2/C was proposed to the introduction of the electron-donating ability of TPA, which may decrease the adsorption affinity of oxygen to the cobalt center. Both dipole-induced partial charge effect and the more exposed cation orbitals of the 3D structural TPA were proposed to contribute to the increased response current of BCP2/C . In addition, BCP2/C attained more than 80% of H 2 O 2 generation in acidic solution, which may also relate to the structural effect. These findings may provide new insight into the structural design of organic electrocatalysts and deep understanding on the interfacial charge transfer mechanism for ORR.
研究领域:
电化学
·
催化
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of the American Chemical Society
·
2024
·
IF 14.4
Fan Ma,Zhi-Mei Luo,Jia-Wei Wang,Gangfeng Ouyang
The development of efficient, selective, and durable CO2 photoreduction systems presents a long-standing challenge in full aqueous solutions owing to the presence of scarce CO2 and the fierce competition against H2 evolution, which is even more challenging when noble metals are not utilized. Herein, we present the facile decorations of four phosphonic acid groups on a donor–acceptor-type organic dye to obtain a water-soluble photosensitizer (4P-DPAIPN), which succeeds the excellent photophysical and photoredox properties of its prototype, exhibiting long-lived delayed fluorescence (>10 μs) in aqueous solutions. Combining 4P-DPAIPN with a cationic cobalt porphyrin catalyst has accomplished record-high apparent quantum yields of 9.4–17.4% at 450 nm for CO2-to-CO photoconversion among the precedented systems (maximum 13%) in fully aqueous solutions. Remarkable selectivity of 82–93% and turnover number of 2700 for CO production can also be achieved with this noble-metal-free system, outperforming a benchmarking ruthenium photosensitizer and a commercial organic dye under parallel conditions. Such high performances of 4P-DPAIPN can be well maintained under real sunlight. More impressively, no significant decomposition of 4P-DPAIPN was detected during the long-term photocatalysis. Eventually, the photoinduced electron transfer pathways were proposed.
研究领域:
化学
·
材料科学
·
环境科学
·
光化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）