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CO 2 reduction through artificial photosynthesis represents a prominent strategy toward the conversion of solar energy into fuels or useful chemical feedstocks. In such configuration, designing highly efficient chromophores comprising earth-abundant elements is essential for both light harvesting and electron transfer. Herein, we report that a copper purpurin complex bearing an additional redox-active center in natural organic chromophores is capable to shift the reduction potential 540 mV more negative than its organic dye component. When this copper photosensitizer is employed with an iron porphyrin as the catalyst and 1,3-dimethyl-2-phenyl-2,3-dihydro-1 H -benzo[ d ]imidazole as the sacrificial reductant, the system achieves over 16100 turnover number of CO from CO 2 with a 95% selectivity (CO vs H 2 ) under visible-light irradiation, which is among the highest reported for a homogeneous noble metal-free system. This work may open up an effective approach for the rational design of highly efficient chromophores in artificial photosynthesis. Designing highly efficient chromophores comprising earth-abundant elements is essential for both light harvesting and electron transfer reactions. Here, authors prepare a copper purpurin complex that shows enhanced photocatalytic activity for CO 2 reduction to CO with a high selectivity.

The fulfillment of a high quantum efficiency for photocatalytic CO 2 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 CO 2 reduction, which is systematically demonstrated by 1 H 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 CO 2 -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. Positioning photosensitizer and catalyst complexes in photocatalytic systems is a promising method to direct desired electron transfers. Here, authors employ a dynamic coordinative interaction between molecular components to improve CO 2 photoreduction to CO with a high quantum efficiency of 27.9%.

Homogeneous systems for light-driven reduction of protons to H 2 typically suffer from short lifetimes because of decomposition of the light-absorbing molecule. We report a robust and highly active system for solar hydrogen generation in water that uses CdSe nanocrystals capped with dihydrolipoic acid (DHLA) as the light absorber and a soluble Ni 2+ -DHLA catalyst for proton reduction with ascorbic acid as an electron donor at pH = 4.5, which gives >600,000 turnovers. Under appropriate conditions, the precious-metal—free system has undiminished activity for at least 360 hours under illumination at 520 nanometers and achieves quantum yields in water of over 36%.

The direct utilization of solar energy to convert CO 2 into renewable chemicals remains a challenge. One essential difficulty is the development of efficient and inexpensive light-absorbers. Here we show a series of aminoanthraquinone organic dyes to promote the efficiency for visible light-driven CO 2 reduction to CO when coupled with an Fe porphyrin catalyst. Importantly, high turnover numbers can be obtained for both the photosensitizer and the catalyst, which has not been achieved in current light-driven systems. Structure-function study performed with substituents having distinct electronic effects reveals that the built-in donor-acceptor property of the photosensitizer significantly promotes the photocatalytic activity. We anticipate this study gives insight into the continued development of advanced photocatalysts for solar energy conversion. A class of inexpensive aminoanthraquinone organic dyes are shown to facilitate visible-light-driven CO 2 reduction. Overall reaction efficiencies were found to be optimal when both electron donating and accepting groups were on a single dye molecule.

Unique tripodal S-donor capping agents with an attached carboxylate are found to bind tightly to the surface of CdSe nanocrystals (NCs), making the latter water soluble. Unlike that in similarly solubilized CdSe NCs with one-sulfur or two-sulfur capping agents, dissociation from the NC surface is greatly reduced. The impact of this behavior is seen in the photochemical generation of H ₂ in which the CdSe NCs function as the light absorber with metal complexes in aqueous solution as the H ₂-forming catalyst and ascorbic acid as the electron donor source. This precious-metal–free system for H ₂ generation from water using [Co(bdt) ₂] ⁻ (bdt, benzene-1,2-dithiolate) as the catalyst exhibits excellent activity with a quantum yield for H ₂ formation of 24% at 520 nm light and durability with >300,000 turnovers relative to catalyst in 60 h.

Exploration of high‐performance cathode materials for rechargeable aqueous Zn ion batteries (ZIBs) is highly desirable. The potential of molybdenum trioxide (MoO3) in other electrochemical energy storage devices has been revealed but held understudied in ZIBs. Herein, a demonstration of orthorhombic MoO3 as an ultrahigh‐capacity cathode material in ZIBs is presented. The energy storage mechanism of the MoO3 nanowires based on Zn2+ intercalation/deintercalation and its electrochemical instability mechanism are particularly investigated and elucidated. The severe capacity decay of the MoO3 nanowires during charging/discharging cycles arises from the dissolution and the structural collapse of MoO3 in aqueous electrolyte. To this end, an effective strategy to stabilize MoO3 nanowires by using a quasi‐solid‐state poly(vinyl alcohol)(PVA)/ZnCl2 gel electrolyte to replace the aqueous electrolyte is developed. The capacity retention of the assembled ZIBs after 400 charge/discharge cycles at 6.0 A g−1 is significantly boosted, from 27.1% (in aqueous electrolyte) to 70.4% (in gel electrolyte). More remarkably, the stabilized quasi‐solid‐state ZIBs achieve an attracting areal capacity of 2.65 mAh cm−2 and a gravimetric capacity of 241.3 mAh g−1 at 0.4 A g−1, outperforming most of recently reported ZIBs. Orthorhombic MoO3 nanowires are demonstrated as an ultrahigh‐capacity cathode material in Zn ion batteries (ZIBs). Benefiting from the unique layered structure and the stabilized MoO3 nanowires, a high‐performance quasisolid state Zn//MoO3 battery with attracting capacity of 2.65 mAh cm−2 (243.1 mAh g−1) and energy density of 14.4 mWh cm−3 as well as decent durability is constituted.

The utilization of low-energy photons in light-driven reactions is an effective strategy for improving the efficiency of solar energy conversion. In nature, photosynthetic organisms use chlorophylls to harvest the red portion of sunlight, which ultimately drives the reduction of CO 2 . However, a molecular system that mimics such function is extremely rare in non-noble-metal catalysis. Here we report a series of synthetic fluorinated chlorins as biomimetic chromophores for CO 2 reduction, which catalytically produces CO under both 630 nm and 730 nm light irradiation, with turnover numbers of 1790 and 510, respectively. Under appropriate conditions, the system lasts over 240 h and stays active under 1% concentration of CO 2 . Mechanistic studies reveal that chlorin and chlorinphlorin are two key intermediates in red-light-driven CO 2 reduction, while corresponding porphyrin and bacteriochlorin are much less active forms of chromophores. Using low-energy photons in light-driven reactions is an effective strategy for improving the efficiency of solar energy conversion but molecular systems that mimic such function are extremely rare in non-noble-metal catalysis. Here the authors report fluorinated chlorins as chromophores for CO 2 reduction, which catalytically produce CO under both 630 nm and 730 nm light irradiation.

Artificial photosynthesis (AP) is a promising method of converting solar energy into fuel (H ₂). Harnessing solar energy to generate H ₂ from H ⁺ is a crucial process in systems for artificial photosynthesis. Widespread application of a device for AP would rely on the use of platinum-free catalysts due to the scarcity of noble metals. Here we report a series of cobalt dithiolene complexes that are exceptionally active for the catalytic reduction of protons in aqueous solvent mixtures. All catalysts perform visible-light-driven reduction of protons from water when paired with [Formula] as the photosensitizer and ascorbic acid as the sacrificial donor. Photocatalysts with electron withdrawing groups exhibit the highest activity with turnovers up to 9,000 with respect to catalyst. The same complexes are also active electrocatalysts in 1∶1 acetonitrile/water. The electrocatalytic mechanism is proposed to be ECEC, where the Co dithiolene catalysts undergo rapid protonation once they are reduced to [Formula]. Subsequent reduction and reaction with H ⁺ lead to H ₂ formation. Cobalt dithiolene complexes thus represent a new group of active catalysts for the reduction of protons.

Urban drone applications require efficient path planning to ensure safe and optimal navigation through complex environments. Drawing inspiration from the collective intelligence of animal groups and electoral processes in human societies, this study integrates hierarchical structures and group interaction behaviors into the standard Particle Swarm Optimization algorithm. Specifically, competitive and supportive behaviors are mathematically modeled to enhance particle learning strategies and improve global search capabilities in the mid-optimization phase. To mitigate the risk of convergence to local optima in later stages, a mutation mechanism is introduced to enhance population diversity and overall accuracy. To address the challenges of urban drone path planning, this paper proposes an innovative method that combines a path segmentation and prioritized update algorithm with a cubic B-spline curve algorithm. This method enhances both path optimality and smoothness, ensuring safe and efficient navigation in complex urban settings. Comparative simulations demonstrate the effectiveness of the proposed approach, yielding smoother trajectories and improved real-time performance. Additionally, the method significantly reduces energy consumption and operation time. Overall, this research advances drone path planning technology and broadens its applicability in diverse urban environments.

In this paper, we address simultaneous control of a flexible spacecraft’s attitude and vibrations in a three-dimensional space under input disturbances and unknown actuator failures. Using Hamilton’s principle, the system dynamics is modeled as an infinite dimensional system captured using partial differential equations. Moreover, a novel adaptive fault tolerant control strategy is developed to suppress the vibrations of the flexible panel in the course of the attitude stabilization. To determine whether the system energies, angular velocities and transverse deflections, remain bounded and asymptotically decay to zero in the case wherein the number of actuator failures is infinite, a Lyapunov-based stability analysis is conducted. Finally, extensive numerical simulations are performed to demonstrate the performance of the proposed adaptive control strategy.