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1.
Dr. Yunling Deng Dr. Sudharsan Dwaraknath Wenhao O. Ouyang Cory J. Matsumoto Stephanie Ouchida Prof. Dr. Yi Lu 《Angewandte Chemie (International ed. in English)》2023,62(20):e202215719
While native CO2-reducing enzymes display remarkable catalytic efficiency and product selectivity, few artificial biocatalysts have been engineered to allow understanding how the native enzymes work. To address this issue, we report cobalt porphyrin substituted myoglobin (CoMb) as a homogeneous catalyst for photo-driven CO2 to CO conversion in water. The activity and product selectivity were optimized by varying pH and concentrations of the enzyme and the photosensitizer. Up to 2000 TON(CO) was attained at low enzyme concentrations with low product selectivity (15 %), while a product selectivity of 74 % was reached by increasing the enzyme loading but with a compromised TON(CO). The efficiency of CO generation and overall TON(CO) were further improved by introducing positively charged residues (Lys or Arg) near the active stie of CoMb, which demonstrates the value of tuning the enzyme secondary coordination sphere to enhance the CO2-reducing performance of a protein-based photocatalytic system. 相似文献
2.
Kang Sun Yunyang Qian Prof. Dr. Hai-Long Jiang 《Angewandte Chemie (International ed. in English)》2023,62(15):e202217565
Photocatalytic water splitting and carbon dioxide (CO2) reduction provide promising solutions to global energy and environmental issues. In recent years, metal-organic frameworks (MOFs), a class of crystalline porous solids featuring well-defined and tailorable structures as well as high surface areas, have captured great interest toward photocatalytic water splitting and CO2 reduction. In this review, the semiconductor-like behavior of MOFs is first discussed. We then summarize the recent advances in photocatalytic water splitting and CO2 reduction over MOF-based materials and focus on the unique advantage of MOFs for clarifying the structure-property relationship in photocatalysis. In addition, some representative characterization techniques have been presented to unveil the photocatalytic kinetics and reaction intermediates in MOF-based systems. Finally, the challenges, and perspectives for future directions are proposed. 相似文献
3.
以商品TiO2-P25为原料,通过浸渍法负载一定量过渡金属Cu,得到一系列不同含量的CuOx/TiO2光催化剂。利用X射线衍射(XRD),X-射线光电子能谱(XPS),BET,高分辨率透射镜(HRTEM),X射线荧光光谱(XRF)和光致发光光谱(PL)等方法对催化剂进行了详细表征,在自建的光催化反应器中评价了气态水光催化还原CO2反应的活性和CH4收率。结果表明负载CuOx后的TiO2纳米材料光催化性能显著提高,其中1%CuOx/TiO2样品紫外光照72 h后,CH4生成量达到了24.86 µmol•gTi-1。同时,CuOx负载量、反应温度、反应时间等因素对CH4收率均有显著影响。 相似文献
4.
Jiong Wang Xiang Huang Shibo Xi Jong‐Min Lee Cheng Wang Yonghua Du Xin Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(38):13666-13673
Immobilization of planar CoII‐2,3‐naphthalocyanine (NapCo) complexes onto doped graphene resulted in a heterogeneous molecular Co electrocatalyst that was active and selective to reduce CO2 into CO in aqueous solution. A systematic study revealed that graphitic sulfoxide and carboxyl dopants of graphene were the efficient binding sites for the immobilization of NapCo through axial coordination and resulted in active Co sites for CO2 reduction. Compared to carboxyl dopants, the sulfoxide dopants further improved the electron communication between NapCo and graphene, which led to the increase of turnover frequency of the Co sites by about 3 times for CO production with a Faradic efficiency up to 97 %. Pristine NapCo in the absence of a graphene support did not display efficient electron communication with the electrode and thus failed to serve as the electrochemical active site for CO2 reduction under the identical conditions. 相似文献
5.
Wenyuan Lyu Dr. Yang Liu Jingyi Zhou Datong Chen Dr. Xin Zhao Dr. Ruiqi Fang Dr. Fengliang Wang Prof. Yingwei Li 《Angewandte Chemie (International ed. in English)》2023,62(42):e202310733
Photocatalytic conversion of low-concentration CO2 is considered as a promising way to simultaneously mitigate the environmental and energy issues. However, the weak CO2 adsorption and tough CO2 activation process seriously compromise the CO production, due to the chemical inertness of CO2 molecule and the formed fragile metal-C/O bond. Herein, we designed and fabricated oxygen vacancy contained Co3O4 hollow nanoparticles on ordered macroporous N-doped carbon framework (Vo−HCo3O4/OMNC) towards photoreduction of low-concentration CO2. In situ spectra and ab initio molecular dynamics simulations reveal that the constructed oxygen vacancy is able to break the local structural symmetry of Co−O−Co sites. The formation of asymmetric active site switches the CO2 configuration from a single-site linear model to a multiple-sites bending one with a highly stable configuration, enhancing the binding and structural polarization of CO2 molecules. As a result, Vo−HCo3O4/OMNC shows unprecedent activity in the photocatalytic conversion of low-concentration CO2 (10 % CO2/Ar) under laboratory light source or even natural sunlight, affording a syngas yield of 337.8 or 95.2 mmol g−1 h−1, respectively, with an apparent quantum yield up to 4.2 %. 相似文献
6.
Zhiming Pan Minghui Liu Pingping Niu Fangsong Guo Xianzhi Fu Xinchen Wang 《物理化学学报》2020,36(1):1906014-0
Artificial photosynthesis is an ideal method for solar-to-chemical energy conversion, wherein solar energy is stored in the form of chemical bonds of solar fuels. In particular, the photocatalytic reduction of CO2 has attracted considerable attention due to its dual benefits of fossil fuel production and CO2 pollution reduction. However, CO2 is a comparatively stable molecule and its photoreduction is thermodynamically and kinetically challenging. Thus, the photocatalytic efficiency of CO2 reduction is far below the level of industrial applications. Therefore, development of low-cost cocatalysts is crucial for significantly decreasing the activation energy of CO2 to achieving efficient photocatalytic CO2 reduction. Herein, we have reported the use of a Ni2P material that can serve as a robust cocatalyst by cooperating with a photosensitizer for the photoconversion of CO2. An effective strategy for engineering Ni2P in an ultrathin layered structure has been proposed to improve the CO2 adsorption capability and decrease the CO2 activation energy, resulting in efficient CO2 reduction. A series of physicochemical characterizations including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and atomic force microscopy (AFM) were used to demonstrate the successful preparation of ultrathin Ni2P nanosheets. The XRD and XPS results confirm the successful synthesis of Ni2P from Ni(OH)2 by a low temperature phosphidation process. According to the TEM images, the prepared Ni2P nanosheets exhibit a 2D and near-transparent sheet-like structure, suggesting their ultrathin thickness. The AFM images further demonstrated this result and also showed that the height of the Ni2P nanosheets is ca 1.5 nm. The photoluminescence (PL) spectroscopy results revealed that the Ni2P material could efficiently promote the separation of the photogenerated electrons and holes in [Ru(bpy)3]Cl2·6H2O. More importantly, the Ni2P nanosheets could more efficiently promote the charge transfer and charge separation rate of [Ru(bpy)3]Cl2·6H2O compared with the Ni2P particles. In addition, the electrochemical experiments revealed that the Ni2P nanosheets, with their high active surface area and charge conductivity, can provide more active centers for CO2 conversion and accelerate the interfacial reaction dynamics. These results strongly suggest that the Ni2P nanosheets are a promising material for photocatalytic CO2 reduction, and can achieve a CO generation rate of 64.8 μmol·h-1, which is 4.4 times higher than that of the Ni2P particles. In addition, the XRD and XPS measurements of the used Ni2P nanosheets after the six cycles of the photocatalytic CO2 reduction reaction demonstrated their high stability. Overall, this study offers a new function for the 2D transition-metal phosphide catalysts in photocatalytic CO2 reduction. 相似文献
7.
Conor L. Rooney Mason Lyons Yueshen Wu Gongfang Hu Maoyu Wang Chungseok Choi Yuanzuo Gao Chun-Wai Chang Gary W. Brudvig Zhenxing Feng Hailiang Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(2):e202310623
Many metal coordination compounds catalyze CO2 electroreduction to CO, but cobalt phthalocyanine hybridized with conductive carbon such as carbon nanotubes is currently the only one that can generate methanol. The underlying structure–reactivity correlation and reaction mechanism desperately demand elucidation. Here we report the first in situ X-ray absorption spectroscopy characterization, combined with ex situ spectroscopic and electrocatalytic measurements, to study CoPc-catalyzed CO2 reduction to methanol. Molecular dispersion of CoPc on CNT surfaces, as evidenced by the observed electronic interaction between the two, is crucial to fast electron transfer to the active sites and multi-electron CO2 reduction. CO, the key intermediate in the CO2-to-methanol pathway, is found to be labile on the active site, which necessitates a high local concentration in the microenvironment to compete with CO2 for active sites and promote methanol production. A comparison of the electrocatalytic performance of structurally related porphyrins indicates that the bridging aza-N atoms of the Pc macrocycle are critical components of the CoPc active site that produces methanol. In situ X-ray absorption spectroscopy identifies the active site as Co(I) and supports an increasingly non-centrosymmetric Co coordination environment at negative applied potential, likely due to the formation of a Co−CO adduct during the catalysis. 相似文献
8.
Dr. Weixin Zou Yingyi Cheng Dr. Yu-Xin Ye Xiaoqian Wei Dr. Qing Tong Prof. Lin Dong Prof. Gangfeng Ouyang 《Angewandte Chemie (International ed. in English)》2023,62(49):e202313392
Photocatalytic CO2 reduction to CH4 requires photosensitizers and sacrificial agents to provide sufficient electrons and protons through metal-based photocatalysts, and the separation of CH4 from by-product O2 has poor applications. Herein, we successfully synthesize a metal-free photocatalyst of a novel electron-acceptor 4,5,9,10-pyrenetetrone (PT), to our best knowledge, this is the first time that metal-free catalyst achieves non-sacrificial photocatalytic CO2 to CH4 and easily separable H2O2. This photocatalyst offers CH4 product of 10.6 μmol ⋅ g−1 ⋅ h−1 under non-sacrificial ambient conditions (room temperature, and only water), which is two orders of magnitude higher than that of the reported metal-free photocatalysts. Comprehensive in situ characterizations and calculations reveal a multi-step reaction mechanism, in which the long-lived oxygen-centered radical in the excited PT provides as a site for CO2 activation, resulting in a stabilized cyclic carbonate intermediate with a lower formation energy. This key intermediate is thermodynamically crucial for the subsequent reduction to CH4 product with the electronic selectivity of up to 90 %. The work provides fresh insights on the economic viability of photocatalytic CO2 reduction to easily separable CH4 in non-sacrificial and metal-free conditions. 相似文献
9.
本文综述了自20世纪80年代以来基于钴配合物的均相光催化二氧化碳还原研究成果,以钴配合物催化剂的结构分类并结合时间顺序回顾了近四十年来该领域的发展轨迹,重点总结了用于光催化二氧化碳还原研究的金属钴配合物的结构、催化活性以及光催化体系的构成等特点,分析了该领域面临的挑战并展望了未来的发展方向。 相似文献
10.
Yan Wang Sibo Wang Xiong Wen Lou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(48):17396-17400
Materials for high‐efficiency photocatalytic CO2 reduction are desirable for solar‐to‐carbon fuel conversion. Herein, highly dispersed nickel cobalt oxyphosphide nanoparticles (NiCoOP NPs) were confined in multichannel hollow carbon fibers (MHCFs) to construct the NiCoOP‐NPs@MHCFs catalysts for efficient CO2 photoreduction. The synthesis involves electrospinning, phosphidation, and carbonization steps and permits facile tuning of chemical composition. In the catalyst, the mixed metal oxyphosphide NPs with ultrasmall size and high dispersion offer abundant catalytically active sites for redox reactions. At the same time, the multichannel hollow carbon matrix with high conductivity and open ends will effectively promote mass/charge transfer, improve CO2 adsorption, and prevent the metal oxyphosphide NPs from aggregation. The optimized hetero‐metal oxyphosphide catalyst exhibits considerable activity for photosensitized CO2 reduction, affording a high CO evolution rate of 16.6 μmol h?1 (per 0.1 mg of catalyst). 相似文献
11.
Job J. C. Struijs Valery Muravev Marcel A. Verheijen Emiel J. M. Hensen Nikolay Kosinov 《Angewandte Chemie (International ed. in English)》2023,62(5):e202214864
The direct catalytic conversion of atmospheric CO2 to valuable chemicals is a promising solution to avert negative consequences of rising CO2 concentration. However, heterogeneous catalysts efficient at low partial pressures of CO2 still need to be developed. Here, we explore Co/CeO2 as a catalyst for the methanation of diluted CO2 streams. This material displays an excellent performance at reaction temperatures as low as 175 °C and CO2 partial pressures as low as 0.4 mbar (the atmospheric CO2 concentration). To gain mechanistic understanding of this unusual activity, we employed in situ X-ray photoelectron spectroscopy and operando infrared spectroscopy. The higher surface concentration and reactivity of formates and carbonyls—key reaction intermediates—explain the superior activity of Co/CeO2 as compared to a conventional Co/SiO2 catalyst. This work emphasizes the catalytic role of the cobalt-ceria interface and will aid in developing more efficient CO2 hydrogenation catalysts. 相似文献
12.
Xu Chi Dr. Zhi-An Lan Qian Chen Dr. Xirui Zhang Prof. Xiong Chen Prof. Guigang Zhang Prof. Xinchen Wang 《Angewandte Chemie (International ed. in English)》2023,62(22):e202303785
Conjugated polymers (CPs) represent a promising platform for photocatalytic CO2 fixation owing to their suitable band structures that meet the requirements of the reduction potential of CO2 to value-added fuels. However, the photocatalytic performance of CPs is rather restrained by the low charge transfer efficiency. Herein, we rationally designed three CPs with a more delocalized electronic transmission channel and planar molecular structure, which are regarded to evidently reduce the exciton binding energy (Eb) and accelerate the internal charge transfer process. Besides, the assembly of suitable electron-output “tentacles” and cocatalysts on the surface of CPs could effectively facilitate interfacial electron delivery. Accordingly, the optimal P-2CN exhibits an apparent quantum yield of 4.6 % at 420 nm for photocatalytic CO2 to CO. Further adjusting the amounts of cyano groups and cocatalysts, the CO selectivity could be obtained in the range of 0–80.5 %. 相似文献
13.
Bo Shang Conor L. Rooney David J. Gallagher Bernie T. Wang Andrey Krayev Hadar Shema Oliver Leitner Nia J. Harmon Langqiu Xiao Colton Sheehan Samuel R. Bottum Elad Gross James F. Cahoon Thomas E. Mallouk Hailiang Wang 《Angewandte Chemie (International ed. in English)》2023,62(4):e202215213
We report a precious-metal-free molecular catalyst-based photocathode that is active for aqueous CO2 reduction to CO and methanol. The photoelectrode is composed of cobalt phthalocyanine molecules anchored on graphene oxide which is integrated via a (3-aminopropyl)triethoxysilane linker to p-type silicon protected by a thin film of titanium dioxide. The photocathode reduces CO2 to CO with high selectivity at potentials as mild as 0 V versus the reversible hydrogen electrode (vs RHE). Methanol production is observed at an onset potential of −0.36 V vs RHE, and reaches a peak turnover frequency of 0.18 s−1. To date, this is the only molecular catalyst-based photoelectrode that is active for the six-electron reduction of CO2 to methanol. This work puts forth a strategy for interfacing molecular catalysts to p-type semiconductors and demonstrates state-of-the-art performance for photoelectrochemical CO2 reduction to CO and methanol. 相似文献
14.
We present herein a Cp*Co(III)‐half‐sandwich catalyst system for electrocatalytic CO2 reduction in aqueous acetonitrile solution. In addition to an electron‐donating Cp* ligand (Cp*=pentamethylcyclopentadienyl), the catalyst featured a proton‐responsive pyridyl‐benzimidazole‐based N,N‐bidentate ligand. Owing to the presence of a relatively electron‐rich Co center, the reduced Co(I)‐state was made prone to activate the electrophilic carbon center of CO2. At the same time, the proton‐responsive benzimidazole scaffold was susceptible to facilitate proton‐transfer during the subsequent reduction of CO2. The above factors rendered the present catalyst active toward producing CO as the major product over the other potential 2e/2H+ reduced product HCOOH, in contrast to the only known similar half‐sandwich CpCo(III)‐based CO2‐reduction catalysts which produced HCOOH selectively. The system exhibited a Faradaic efficiency (FE) of about 70% while the overpotential for CO production was found to be 0.78 V, as determined by controlled‐potential electrolysis. 相似文献
15.
Prof. Zhiqiang Jiang Prof. Minyi Zhang Xingliang Chen Bing Wang Wenjuan Fan Chenhuai Yang Xiaoju Yang Prof. Zhicheng Zhang Prof. Xuan Yang Prof. Chunsen Li Prof. Tianhua Zhou 《Angewandte Chemie (International ed. in English)》2023,62(45):e202311223
Zeolitic metal–organic frameworks (ZMOFs) have emerged as one of the most promsing catalysts for energy conversion, but they suffer from either weak bonding between metal-organic cubes (MOCs) that decrease their stability during catalysis processes or low activity due to inadequate active sites. In this work, through ligand-directing strategy, we successfully obtain an unprecedented bismuth-based ZMOF (Bi-ZMOF) featuring a ACO topological crystal structure with strong coordination bonding between the Bi-based cages. As a result, it enables efficient reduction of CO2 to formic acid (HCOOH) with Faradaic efficiency as high as 91 %. A combination of in situ surface-enhanced infrared absorption spectroscopy and density functional theory calculation reveals that the Bi−N coordination contributes to facilitating charge transfer from N to Bi atoms, which stabilize the intermediate to boost the reduction efficiency of CO2 to HCOOH. This finding highlights the importance of the coordination environment of metal active sites on electrocatalytic CO2 reduction. We believe that this work will offer a new clue to rationally design zeolitic MOFs for catalytic reaction 相似文献
16.
17.
Ling-Ya Peng Guang-Ning Pan Wen-Kai Chen Xiang-Yang Liu Wei-Hai Fang Ganglong Cui 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(5):e202315300
Photocatalytic CO2 reduction is one of the best solutions to solve the global energy crisis and to realize carbon neutralization. The tetradentate phosphine-bipyridine (bpy)-phosphine (PNNP)-type Ir(III) photocatalyst, Mes-IrPCY2, was reported with a high HCOOH selectivity but the photocatalytic mechanism remains elusive. Herein, we employ electronic structure methods in combination with radiative, nonradiative, and electron transfer rate calculations, to explore the entire photocatalytic cycle to either HCOOH or CO, based on which a new mechanistic scenario is proposed. The catalytic reduction reaction starts from the generation of the precursor metal-to-ligand charge transfer (3MLCT) state. Subsequently, the divergence happens from the 3MLCT state, the single electron transfer (SET) and deprotonation process lead to the formation of one-electron-reduced species and Ir(I) species, which initiate the reduction reaction to HCOOH and CO, respectively. Interestingly, the efficient occurrence of proton or electron transfer reduces barriers of critical steps. In addition, nonadiabatic transitions play a nonnegligible role in the cycle. We suggest a lower free-energy barrier in the reaction-limiting step and the very efficient SET in 3MLCT are cooperatively responsible for a high HCOOH selectivity. The gained mechanistic insights could help chemists to understand, regulate, and design photocatalytic CO2 reduction reaction of similar function-integrated molecular photocatalyst. 相似文献
18.
Dr. Soumen Dutta Akshay Gurumoorthi Shinbi Lee Sun Woo Jang Dr. Nitee Kumari Yu-Rim Hong Prof. Dr. Wonyong Choi Prof. Dr. Chang Yun Son Prof. Dr. In Su Lee 《Angewandte Chemie (International ed. in English)》2023,62(28):e202303890
Herein, by choosing few-nm-thin two-dimensional (2D) nanocrystals of MOF-5 containing in-planner square lattices as a modular platform, a crystal lattice-guided wet-chemical etching has been rationally accomplished. As a result, two attractive pore patterns carrying Euclidean curvatures; precisely, plus(+)-shaped and fractal-patterned pores via ⟨100⟩ and ⟨110⟩ directional etching, respectively, are regulated in contrast to habitually formed spherical-shaped random etches on MOF surface. In agreement with the theoretical calculations, a diffusion-limited etching process has been optimized to devise high-yield of size-tunable fractal-pores on the MOF surface that tenders for a compatibly high payload of catalytic ReI-complexes using the existing large edge area once modified into a free amine-group-exposed inner pore surface. Finally, on benefiting from the long-range fractal opening in 2D MOF support structure, while loaded on an electrode surface, a facilitated cross-interface charge-transportation and well-exposure of immobilized ReI-catalysts are anticipated, thus realizing enhanced activity and stability of the supported catalyst in photoelectrochemical CO2-to-CO reduction. 相似文献
19.
Hainan Shi Dr. Saran Long Dr. Jungang Hou Dr. Lu Ye Yanwei Sun Wenjun Ni Dr. Chunshan Song Dr. Keyan Li Dr. Gagik G. Gurzadyan Dr. Xinwen Guo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(19):5028-5035
Fundamental photocatalytic limitations of solar CO2 reduction remain due to low efficiency, serious charge recombination, and short lifetime of catalysts. Herein, two-dimensional graphitic carbon nitride nanosheets with nitrogen vacancies (g-C3Nx) located at both three-coordinate N atoms and uncondensed terminal NHx species were prepared by one-step tartaric acid-assistant thermal polymerization of dicyandiamide. Transient absorption spectra revealed that the defects in g-C3N4 act as trapped states of charges to result in prolonged lifetimes of photoexcited charge carriers. Time-resolved photoluminescence spectroscopy revealed that the faster decay of charges is due to the decreased interlayer stacking distance in g-C3Nx in favor of hopping transition and mobility of charge carriers to the surface of the material. Owing to the synergic virtues of strong visible-light absorption, large surface area, and efficient charge separation, the g-C3Nx nanosheets with negligible loss after 15 h of photocatalysis exhibited a CO evolution rate of 56.9 μmol g−1 h−1 under visible-light irradiation, which is roughly eight times higher than that of pristine g-C3N4. This work presents the role of defects in modulating light absorption and charge separation, which opens an avenue to robust solar-energy conversion performance. 相似文献
20.
Dr. Fazalurahman Kuttassery Yutaka Ohsaki Dr. Arun Thomas Ryutaro Kamata Yosuke Ebato Dr. Hiromu Kumagai Ryosuke Nakazato Dr. Abin Sebastian Dr. Siby Mathew Prof. Hiroshi Tachibana Prof. Osamu Ishitani Prof. Haruo Inoue 《Angewandte Chemie (International ed. in English)》2023,62(40):e202308956
Bio-inspired molecular-engineered systems have been extensively investigated for the half-reactions of H2O oxidation or CO2 reduction with sacrificial electron donors/acceptors. However, there has yet to be reported a device for dye-sensitized molecular photoanodes coupled with molecular photocathodes in an aqueous solution without the use of sacrificial reagents. Herein, we will report the integration of SnIV- or AlIII-tetrapyridylporphyrin (SnTPyP or AlTPyP) decorated tin oxide particles (SnTPyP/SnO2 or AlTPyP/SnO2) photoanode with the dye-sensitized molecular photocathode on nickel oxide particles containing [Ru(diimine)3]2+ as the light-harvesting unit and [Ru(diimine)(CO)2Cl2] as the catalyst unit covalently connected and fixed within poly-pyrrole layer (RuCAT-RuC2-PolyPyr-PRu/NiO). The simultaneous irradiation of the two photoelectrodes with visible light resulted in H2O2 on the anode and CO, HCOOH, and H2 on the cathode with high Faradaic efficiencies in purely aqueous conditions without any applied bias is the first example of artificial photosynthesis with only two-electron redox reactions. 相似文献