Single PEDOT Catalyst Boosts CO2 Photoreduction Efficiency
Ontology highlight
ABSTRACT:
SUBMITTER: Diao Y
PROVIDER: S-EPMC8554841 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:The sunlight-driven reduction of CO2 into carbonaceous fuels can lower the atmospheric CO2 concentration and provide renewable energy simultaneously, attracting scientists to design photocatalytic systems for facilitating this process. Significant progress has been made in designing high-performance photosensitizers and catalysts in this regard, and further improvement can be realized by installing additional interactions between the abovementioned two components, however, the design strategies and mechanistic investigations on such interactions remain challenging. Here, we present the construction of molecular models for intermolecular π-π interactions between the photosensitizer and the catalyst, via the introduction of pyrene groups into both molecular components. The presence, types, and strengths of diverse π-π interactions, as well as their roles in the photocatalytic mechanism, have been examined by 1H NMR titration, fluorescence quenching measurements, transient absorption spectroscopy, and quantum chemical simulations. We have also explored the rare dual emission behavior of the pyrene-appended iridium photosensitizer, of which the excited state can deliver the photo-excited electron to the pyrene-decorated cobalt catalyst at a fast rate of 2.60 × 106 s-1 via co-facial π-π interaction, enabling a remarkable apparent quantum efficiency of 14.3 ± 0.8% at 425 nm and a high selectivity of 98% for the photocatalytic CO2-to-CO conversion. This research demonstrates non-covalent interaction construction as an effective strategy to achieve rapid CO2 photoreduction besides a conventional photosensitizer/catalyst design.
| S-EPMC9241016 | biostudies-literature
Project description:The design of a highly efficient system for CO2 photoreduction fully based on earth-abundant elements presents a challenge, which may be overcome by installing suitable interactions between photosensitizer and catalyst to expedite the intermolecular electron transfer. Herein, we have designed a pyrene-decorated Cu(I) complex with a rare dual emission behavior, aiming at additional π-interaction with a pyrene-appended Co(II) catalyst for visible light-driven CO2-to-CO conversion. The results of 1H NMR titration, time-resolved fluorescence/absorption spectroscopies, quantum chemical simulations, and photocatalytic experiments clearly demonstrate that the dynamic π-π interaction between sensitizer and catalyst is highly advantageous in photocatalysis by accelerating the intermolecular electron transfer rate up to 6.9 × 105 s-1, thus achieving a notable apparent quantum yield of 19% at 425 nm with near-unity selectivity. While comparable to most earth-abundant molecular systems, this value is over three times of the pyrene-free system (6.0%) and far surpassing the benchmarking Ru(II) tris(bipyridine) (0.3%) and Ir(III) tris(2-phenylpyridine) (1.4%) photosensitizers under parallel conditions.
| S-EPMC10068849 | biostudies-literature
Project description:In this paper, a novel photocatalyst CNCC with excellent visible light photocatalytic performance was successfully prepared to optimize the CO2 photoreduction performance. The results showed that the methanol formation rate of CNCC was 24.7 µmol g-1 h-1, which was 1.42 times higher than that of NCC. The enhanced photoactivity is attributed to the rapid propagation of charge carriers induced by light from the constructed composite structure.
| S-EPMC6458405 | biostudies-literature
Project description:Photocatalytic conversion of CO2 into transportable fuels such as formic acid (HCOOH) under sunlight is an attractive solution to the shortage of energy and carbon resources as well as to the increase in Earth's atmospheric CO2 concentration. The use of abundant elements as the components of a photocatalytic CO2 reduction system is important, and a solid catalyst that is active, recyclable, nontoxic, and inexpensive is strongly demanded. Here, we show that a widespread soil mineral, alpha-iron(III) oxyhydroxide (α-FeOOH; goethite), loaded onto an Al2 O3 support, functions as a recyclable catalyst for a photocatalytic CO2 reduction system under visible light (λ>400 nm) in the presence of a RuII photosensitizer and an electron donor. This system gave HCOOH as the main product with 80-90 % selectivity and an apparent quantum yield of 4.3 % at 460 nm, as confirmed by isotope tracer experiments with 13 CO2 . The present work shows that the use of a proper support material is another method of catalyst activation toward the selective reduction of CO2 .
| S-EPMC9325401 | biostudies-literature
Project description:Improving the photocatalytic efficiency of a fully noble-metal-free system for CO2 reduction remains a fundamental challenge, which can be accomplished by facilitating electron delivery as a consequence of exploiting intermolecular interactions. Herein, we have designed two Cu(I) photosensitizers with different pyridyl pendants at the phenanthroline moiety to enable dynamic coordinative interactions between the sensitizers and a cobalt macrocyclic catalyst. Compared to the parent Cu(I) photosensitizer, one of the pyridine-tethered derivatives boosts the apparent quantum yield up to 76 ± 6% at 425 nm for selective (near 99%) CO2-to-CO conversion. This value is nearly twice that of the parent system with no pyridyl pendants (40 ± 5%) and substantially surpasses the record (57%) of the noble-metal-free systems reported so far. This system also realizes a maximum turnover number of 11 800 ± 1400. In contrast, another Cu(I) photosensitizer, in which the pyridine substituents are directly linked to the phenanthroline moiety, is inactive. The above behavior and photocatalytic mechanism are systematically elucidated by transient fluorescence, transient absorption, transient X-ray absorption spectroscopies, and quantum chemical calculations. This work highlights the advantage of constructing coordinative interactions to fine-tune the electron transfer processes within noble-metal-free systems for CO2 photoreduction.
| S-EPMC10369415 | biostudies-literature
Project description:The fulfillment of a high quantum efficiency for photocatalytic CO2 reduction presents a key challenge, which can be overcome by developing strategies for dynamic attachment between photosensitizer and catalyst. In this context, we exploit the use of coordinate bond to connect a pyridine-appended iridium photosensitizer and molecular catalysts for CO2 reduction, which is systematically demonstrated by 1H nuclear magnetic resonance titration, theoretical calculations, and spectroscopic measurements. The mechanistic investigations reveal that the coordinative interaction between the photosensitizer and an unmodified cobalt phthalocyanine significantly accelerates the electron transfer and thus realizes a remarkable quantum efficiency of 10.2% ± 0.5% at 450 nm for photocatalytic CO2-to-CO conversion with a turn-over number of 391 ± 7 and nearly complete selectivity, over 4 times higher than a comparative system with no additional interaction (2.4%±0.2%). Moreover, the decoration of electron-donating amino groups on cobalt phthalocyanine can optimize the quantum efficiency up to 27.9% ± 0.8% at 425 nm, which is more attributable to the enhanced coordinative interaction rather than the intrinsic activity. The control experiments demonstrate that the dynamic feature of coordinative interaction is important to prevent the coordination occupancy of labile sites, also enabling the wide applicability on diverse non-noble-metal catalysts.
| S-EPMC8277789 | biostudies-literature
Project description:The surface electron density significantly affects the photocatalytic efficiency, especially the photocatalytic CO2 reduction reaction, which involves multi-electron participation in the conversion process. Herein, we propose a conceptually different mechanism for surface electron density modulation based on the model of Au anchored CdS. We firstly manipulate the direction of electron transfer by regulating the vacancy types of CdS. When electrons accumulate on vacancies instead of single Au atoms, the adsorption types of CO2 change from physical adsorption to chemical adsorption. More importantly, the surface electron density is manipulated by controlling the size of Au nanostructures. When Au nanoclusters downsize to single Au atoms, the strong hybridization of Au 5d and S 2p orbits accelerates the photo-electrons transfer onto the surface, resulting in more electrons available for CO2 reduction. As a result, the product generation rate of AuSA/Cd1-xS manifests a remarkable at least 113-fold enhancement compared with pristine Cd1-xS.
| S-EPMC7960986 | biostudies-literature
Project description:Incorporation of earth-abundant Cu is one of the most important approaches to improve the practicability of TiO2 for photoreduction of CO2 into value-added solar fuels. However, the molecular insight on the role of Cu is complicated and far from understood. We performed a first principle calculation on the anatase (101) surface modified by a single Cu atom deposited on the surface (CuS) or doped in the lattice (CuL). It is demonstrated the CuL is clearly more stable than the CuS and could promote the formation of oxygen vacancy (Vo) greatly. The CuS plays a role of donor, while the CuL is electronically deficient and becomes a global electron trapper. If a Vo is introduced, the excess electrons would immigrate to the empty gap state of the CuL and make it half-filled in some case, which implies its metallic characters and improved conductivity; meanwhile, the formation of Ti3+ is suppressed. Judging from the adsorption energies, it is the Vo that primarily improves the adsorption of CO2 in both linear and bent states, and the CuS could hardly stabilize CO2 more, while the promotion effect of Vo could even be counteracted by the CuL due to its electronic deficiency. The reduction pathways (CO2* → CO* + O*) show that, with the assistance of the CuS, linear CO2 could directly transform into the carbonate-like geometry vertically binding to the surface, and the intermediate configuration of the bent CO2 horizontally bridging the Vo could be successfully skipped. Therefore, the barrier of the rate-determining transformation could be lowered from 0.75 to 0.39 eV. Furthermore, it is found the strong adsorption of the produced CO by the CuS might retard the smooth going of the catalytic process.
| S-EPMC7391363 | biostudies-literature
Project description:Metal-Organic Framework (MOF)-derived TiO2, synthesised through the calcination of MIL-125-NH2, is investigated for its potential as a CO2 photoreduction catalyst. The effect of the reaction parameters: irradiance, temperature and partial pressure of water was investigated. Using a two-level design of experiments, we were able to evaluate the influence of each parameter and their potential interactions on the reaction products, specifically the production of CO and CH4. It was found that, for the explored range, the only statistically significant parameter is temperature, with an increase in temperature being correlated to enhanced production of both CO and CH4. Over the range of experimental settings explored, the MOF-derived TiO2 displays high selectivity towards CO (98%), with only a small amount of CH4 (2%) being produced. This is notable when compared to other state-of-the-art TiO2 based CO2 photoreduction catalysts, which often showcase lower selectivity. The MOF-derived TiO2 was found to have a peak production rate of 8.9 × 10-4 μmol cm-2 h-1 (2.6 μmol g-1 h-1) and 2.6 × 10-5 μmol cm-2 h-1 (0.10 μmol g-1 h-1) for CO and CH4, respectively. A comparison is made to commercial TiO2, P25 (Degussa), which was shown to have a similar activity towards CO production, 3.4 × 10-3 μmol cm-2 h-1 (5.9 μmol g-1 h-1), but a lower selectivity preference for CO (3 : 1 CH4 : CO) than the MOF-derived TiO2 material developed here. This paper showcases the potential for MIL-125-NH2 derived TiO2 to be further developed as a highly selective CO2 photoreduction catalyst for CO production.
| S-EPMC10193832 | biostudies-literature
Project description:The design of efficient and stable photocatalysts for robust CO2 reduction without sacrifice reagent or extra photosensitizer is still challenging. Herein, a single-atom catalyst of isolated single atom cobalt incorporated into Bi3O4Br atomic layers is successfully prepared. The cobalt single atoms in the Bi3O4Br favors the charge transition, carrier separation, CO2 adsorption and activation. It can lower the CO2 activation energy barrier through stabilizing the COOH* intermediates and tune the rate-limiting step from the formation of adsorbed intermediate COOH* to be CO* desorption. Taking advantage of cobalt single atoms and two-dimensional ultrathin Bi3O4Br atomic layers, the optimized catalyst can perform light-driven CO2 reduction with a selective CO formation rate of 107.1 µmol g-1 h-1, roughly 4 and 32 times higher than that of atomic layer Bi3O4Br and bulk Bi3O4Br, respectively.
| S-EPMC6599015 | biostudies-literature