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A cyanide-bridged di-manganese carbonyl complex that photochemically reduces CO <sub/>2</sub> to CO
摘要： A cyanide-bridged di-manganese carbonyl complex that photochemically reduces CO2 to CO? Hsin-Ya Kuo, Tia S. Lee, An T. Chu, Steven E. Tignor, Gregory D. Scholes and Andrew B. Bocarsly* Manganese(I) tricarbonyl complexes such as [Mn(bpy)(CO)3L] (L = Br, or CN) are known to be electrocatalysts for CO2 reduction to CO. However, due to their rapid photodegradation under UV and visible light, these monomeric manganese complexes have not been considered as photocatalysts for CO2 reduction without the use of a photosensitizer. In this paper, we report a cyanide-bridged di-manganese complex, {[Mn(bpy)(CO)3]2(μ-CN)}ClO4, which is both electrocatalytic and photochemically active for CO2 reduction to CO. Compared to the [Mn(bpy)(CO)3CN] electrocatalyst, our CN-bridged binuclear complex is a more efficient electrocatalyst for CO2 reduction using H2O as a proton source. In addition, we report a photochemical CO2 reduction to CO using the dimanganese complex under 395 nm irradiation.
关键词： electrocatalyst,cyanide-bridged,photochemical reduction,CO2 reduction,di-manganese,photocatalyst,carbonyl complex
更新于2025-11-19 16:56:42
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Sensitized photochemical CO2 reduction by hetero-Pacman compounds linking a Re(I) tricarbonyl with a porphyrin unit
摘要： The hetero-Pacman architecture places two different metal coordination sites in close proximity, which can support efficient energy and/or electron transfer and allow for cooperative activation of small molecules. Herein, we present the synthesis of dyads consisting of a porphyrin unit as photosensitizer and a rhenium unit as catalytically active site, which are held together by the rigid xanthene backbone. Mononuclear [(NN)Re(CO)3(Cl)] complexes for CO2 reduction where NN represents a bidentate diimine ligand (e.g. bipyridine or phenanthroline) lack light absorption in the visible region, resulting in poor photocatalysis upon illumination with visible light. In order to improve their visible light absorption, we have focused on the incorporation of a strongly absorbing free base or zinc porphyrin unit. Resulting photocatalytic experiments showed a strong dependence of catalytic performance on both the type of photosensitizer and also the excitation wavelengths. Most notably, the intramolecular hetero-Pacman system containing a zinc porphyrin unit showed much better catalytic activity in the visible region (excitation wavelengths >450 nm) than the free base version, the corresponding mononuclear rhenium compound or an intermolecular system comprised of a 1:1 mixture of the mononuclear analogues.
关键词： photocatalysis,CO2 reduction,electron transfer,porphyrin,rhenium
更新于2025-11-19 16:56:35
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Probing the Role of Nickle Dopant in Aqueous Colloidal ZnS Nanocrystals for Efficient Solar-Driven CO2 Reduction
摘要： Photocatalytic CO2 reduction reaction (CO2RR) on a heterogeneous catalyst offers the possibility for CO2 abatement and emerges as a promising avenue for renewable carbonaceous fuels production at ambient temperature and pressure using solar light as the sole energy input. Here, we report a newly aqueous colloidal comprised of monodispersed Ni-doped ZnS (ZnS:Ni) nanocrystals as excellent visible-light-responsive photocatalysts for CO2RR into formate. The wavelength-dependent quantum yield shows a significant contribution of Ni doping for visible light absorption. A high selectivity (>95%) of HCOOH production and a remarkable quantum efficiency of 59.1% at 340 nm and 5.6 % at 420 nm are obtained over ZnS:Ni (0.1 %) colloidal nanocrystals modified by Cd2+. The abundant sulfur vacancies and extended visible light absorption of the constructed colloidal ZnS:Ni nanocrystals contribute to the prominent performance for CO2RR. However, excessive doping of Ni does not guarantee an increase of photocatalytic CO2RR due to a diminish of sulfur vacancy. The regulation of sulfur vacancies by Ni doping and their interplay on photocatalytic CO2RR activity are presented and discussed. This work provides an in-depth insight of the role of dopant on vacancy modulation in photocatalyst beyond light absorption and a guidance for design of the potential photocatalyst for CO2RR.
关键词： CO2 reduction,vacancy,photocatalysis,doping,ZnS
更新于2025-11-19 16:51:07
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Lewis acid activated CO <sub/>2</sub> reduction over a Ni modified Ni–Ge hydroxide driven by visible-infrared light
摘要： Improvement of light harvesting and reaction kinetics is of great importance for achieving efficient solar-driven CO2 reduction. Here, a Ni modified low-crystalline Ni–Ge containing hydroxide with Lewis acid sites was synthesized in highly reductive NaBH4 solution and exhibited 9.3 μmol gcat.?1 h?1 CO and 3.5 μmol gcat.?1 h?1 CH4 generation rates under visible light irradiation, and even achieved a 3.8 μmol gcat.?1 h?1 CO evolution under infrared light irradiation. The wide-spectrum light harvesting resulted from the light absorption from the localized surface plasmonic resonance of Ni nanoparticles. In addition, the Lewis acid can activate CvO bonds to decrease the kinetic barriers of CO2 reduction. The design concept that rationally combines the advantages of expanding the spectral response and activating CO2 may offer a new strategy for efficient solar energy utilization.
关键词： visible-infrared light,plasmonic effect,Lewis acid,CO2 reduction,photocatalyst
更新于2025-11-19 16:51:07
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Wafer-Scale Si Nanoconed Arrays Induced Syngas in the Photoelectrochemical CO2 Reduction
摘要： Photoelectrochemical (PEC) CO2 reduction offers a promising way to carry out the CO2 sequestration and develop the carbon-neutral technology. Doped Si is by far one of the most technologically important semiconductors with high conductivity and narrow bandgap, potential for CO2 reduction. However, the previous reports on PEC CO2 reduction over Si electrodes were not involved with many nanostructures. Syngas, a kind of chemical feedstocks and a crucial intermediate for hydrocarbon fuels, is highly demanded for industry. Herein, we used a wafer-scale nanoconed Si arrays substrate to load the metallic nanoparticles (Au and Cu). Effective PEC CO2 reduction into syngas was achieved in the aqueous solution with no sacrificial reagents. In contrast, planar Si seldom generated CO under the same reactant environment. Our finding deepens the comprehension of PEC CO2 reduction over the nanostructured materials and gives an inspiration for rational design of the PEC catalysts towards solar-to-chemical conversion.
关键词： Si,photoelectrochemical (PEC),CO2 reduction,nanostructure,syngas
更新于2025-11-19 16:51:07
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Probing Electrocatalytic CO2 Reduction at Individual Cu Nanostructures via Optically Targeted Electrochemical Cell Microscopy
摘要： Optically targeted electrochemical cell microscopy (OTECCM) was applied to measure electrocatalytic rates at individual Cu nanoparticles (NPs) under electrolyte conditions relevant to CO2 reduction. The electrocatalytic responses from individual NPs were found to exhibit a wide variation in behavior, with significant NP-to-NP variations in the magnitude of electrocatalytic currents and necessary overpotentials being observed. Correlations of these quantities with metrics of NP size suggest no significant variations in the inherent electrocatalytic activity of the NPs with size. Finite element simulations of diffusion in this system demonstrate the observed diffusion-limited currents are significantly smaller than expected, attributable to the presence of a significant amount of residual ligand on the surface of the Cu NPs, which were prepared via an organic phase synthesis. The results presented here further demonstrate the promise of techniques which employ correlated optical and electrochemical measurements, such as OTECCM, for studying electrocatalysis at individual NPs.
关键词： Nanoparticles,Electrochemical microscopy,Electrochemistry,CO2 reduction
更新于2025-11-14 17:03:37
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Three-in-one oxygen vacancy: whole visible-spectrum absorption, efficient charge separation and surface site activation for robust CO2 photoreduction
摘要： Exploitation of efficient catalysts to realize solar-driven conversion of inert CO2 into useful fuels confronts big challenges owing to the poor photoabsorption, sluggish charge separation and inefficient surface reactive sites of photocatalysts. Herein, we report a facile and controllable in situ reduction strategy to create surface oxygen vacancies (OVs) on Aurivillius-phase Sr2Bi2Nb2TiO12 nanosheets. Sr2Bi2Nb2TiO12 nanosheets are for the first time prepared by a mineralizer-assisted soft-chemical method, and the introduction of OVs on the surface of Sr2Bi2Nb2TiO12 not only extends photo-response region, but also tremendously promotes separation of photo-induced charge carriers. Moreover, the adsorption and activation of CO2 molecules on the surface of the catalyst are largely enhanced. In the gas-solid reaction system without any co-catalysts or sacrificial agents, OVs-abundant Sr2Bi2Nb2TiO12 nanosheets show an outstanding CO2 photoreduction activity in producing CO with a rate of 17.11 μmol g?1 h?1, ~58 times higher than that of the bulk counterpart, surpassing most previously reported state-of-the-art photocatalysts. Our study provides a three-in-one integrated solution to advance the comprehensive performance of photocatalysts for solar-energy conversion and generation of renewable energy.
关键词： Sr2Bi2Nb2TiO12 nanosheets,charge separation,photocatalytic CO2 reduction,oxygen vacancies
更新于2025-09-23 15:23:52
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Au as a cocatalyst loaded on solid solution Bi0.5Y0.5VO4 for enhancing photocatalytic CO2 reduction activity
摘要： Au as a cocatalyst was deposited on the surface of solid solution Bi0.5Y0.5VO4 by a photodeposition method for photocatalytic reduction of CO2. Au particles loaded on the surface of Bi0.5Y0.5VO4 apparently enhanced the photocatalytic activity of CO2 reduction toward CO evolution. The highest rate of CO evolution was obtained over 1.0 wt% Au/Bi0.5Y0.5VO4, reaching 3.5 times of that of bare Bi0.5Y0.5VO4. The improved photocatalytic performance was assigned to the lower overpotential of Au/Bi0.5Y0.5VO4 for CO evolution than that of bare Bi0.5Y0.5VO4 as well as the formation of Schottky barrier, which promotes the separation of photogenerated electron–hole pairs.
关键词： Semiconductors,Au cocatalyst,Nanocomposites,CO2 reduction,Charge separation
更新于2025-09-23 15:23:52
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Photosensitizing single-site metal?organic framework enabling visible-light-driven CO2 reduction for syngas production
摘要： Photocatalytic CO2 reduction into syngas (CO and H2) is one of sustainable strategies for recycling CO2 into value-added products. Herein, a simple and effective two-step self-assembly process was developed to functionalize phosphorescent metal-organic framework (MOF) with single site catalyst. The resulting (Co/Ru)n-UiO-67(bpydc) supplied molecular platform to enable fast multielectron injection from photosensitizers (PSs) to Co-catalyst, leading to the first MOF-based composite photocatalyst for efficient syngas production with a yield of 13600 μmol·g?1 (H2 : CO = 2 : 1) in 16 h, 29.2-fold higher than that of its homogeneous counterpart. The H2/CO ratios can be well controlled by carefully adjusting the molar ratio of PS/catalyst in the MOF platform and the water content in the photocatalytic system. This work provides a prospective strategy for recycling CO2 into H2-rich syngas by merging PSs and single-site catalysts into a MOF platform.
关键词： Metal-organic framework,CO2 reduction,photosensitizer,photocatalyst,syngas
更新于2025-09-23 15:23:52
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Synthesis of bismuth molybdate photocatalysts for CO2 photo-reduction
摘要： To explore the possibilities of bismuth molybdate in CO2 photo-reduction to chemicals and fuels, two types of bismuth molybdate namely Bi2MoO6 and Bi3.64Mo0.36O6.55 were synthesized via hydrothermal treatment by adjusting the pH of reaction solution. Bi2MoO6 is constituted by MoO6 octahedra while Bi3.64Mo0.36O6.55 is constructed by MoO4 tetrahedra. Different structure causes quite different properties, like electron binding energy, photoluminescence character, band edge position, optical and electrochemical properties. Comprehensively speaking, Bi2MoO6 made the most of solar energy and showed relatively more efficient charge migration and separation efficiency, contributing to its higher activity for CO2 photo-reduction. After irradiating for 5 h, the yields of CO gas over the both samples were 85.5172 (Bi2MoO6) and 57.3259 (Bi3.64Mo0.36O6.55) μmol/g, respectively. Last, the photocatalytic reduction mechanism was analyzed.
关键词： CO2 reduction,Bi3.64Mo0.36O6.55,Photocatalysis,Bi2MoO6
更新于2025-09-23 15:23:52