Chemical Reviews最新文献

Organic materials have emerged as highly efficient electrodes for electrochemical energy storage, offering sustainable solutions independent from non-renewable resources. In this study, we showcase that mesoscale engineering can dramatically transform the electrochemical features of a molecular organic carboxylic anode. Through a sustainable, energy-efficient and environmentally benign self-assembly strategy, we developed a network of organic nanowires formed during water evaporation directly on the copper current collector, circumventing the need for harmful solvents, typically employed in such processes. The organic nanowire anode delivers high capacity and rate, reaching 1888 mA h g⁻¹ at 0.1 A g⁻¹ and maintaining 508 mA h g⁻¹ at a specific current of 10 A g⁻¹. Moreover, it exhibits superior thermal management during lithiation in comparison to graphite and other organic anodes. Comprehensive electrochemical evaluations and theoretical calculations reveal rapid charge transport mechanisms, with lithium diffusivity rates reaching 5 × 10⁻⁹ cm² s⁻¹, facilitating efficient and rapid interactions with 24 lithium atoms per molecule. Integrated as the negative electrode in a lithium-ion capacitor, paired with a commercially available porous carbon, the cell delivers a specific energy of 156 W h kg⁻¹ at a specific power of 0.34 kW kg⁻¹ and 60.2 W h kg⁻¹ at 19.4 kW kg⁻¹, establishing a benchmark among state-of-the-art systems in the field. These results underscore the critical role of supramolecular organization for optimizing the performance of organic electrode materials for practical and sustainable energy storage technologies.

The detrimental impact of non-geminate recombination on high-performance organic photovoltaics has been recognised and primarily attributed to bimolecular recombination. However, the recent surge in Y-series acceptor-based systems has drawn attention to deep-trap-assisted monomolecular recombination. This study reveals the morphological origin of deep traps in the prototypical PM6:Y6 system, identifying isolated crystalline and amorphous Y6 domains as key contributors. The findings underscore the importance of improving inter-acceptor domain connectivity for effective trap passivation. For the first time, we have pinpointed a crucial metric for inversely quantifying the inter-acceptor domain connectivity: the crystalline domain fractal dimension (D_f). Due to the self-similar nature of fractal structures, the fractal dimension propagates across multi-length scales and can be controlled by tuning local intermolecular aggregation motifs. Remarkably, combining diiodide benzene (DIB) as the additive and layer-by-layer (LBL) processing effectively promotes the more extended backbone order of Y6 molecules, consequently reducing the fractal dimensions and passivating deep traps. By applying this strategy to another high-performance system, D18:L8BO, a benchmark efficiency of 19.6% is achieved, among the highest efficiencies reported for LBL OPVs.

Quantum walks on photonic platforms represent a physics-rich framework for quantum measurements, simulations and universal computing. Dynamic reconfigurability of photonic circuitry is key to controlling the walk and retrieving its full operation potential. Universal quantum processing schemes based on time-bin encoding in gated fibre loops have been proposed but not demonstrated yet, mainly due to gate inefficiencies. Here we present a scalable quantum processor based on the discrete-time quantum walk of time-bin-entangled photon pairs on synthetic temporal photonic lattices implemented on a coupled fibre-loop system. We utilize this scheme to path-optimize quantum state operations, including the generation of two- and four-level time-bin entanglement and the respective two-photon interference. The design of the programmable temporal photonic lattice enabled us to control the dynamic of the walk, leading to an increase in the coincidence counts and quantum interference measurements without recurring to post-selection. Our results show how temporal synthetic dimensions can pave the way towards efficient quantum information processing, including quantum phase estimation, Boson sampling and the realization of topological phases of matter for high-dimensional quantum systems in a cost-effective, scalable and robust fibre-based setup.

Van der Waals engineering serves as a powerful tool to tailor material properties and design excitonic devices. Here we report quantum-entangled photon pair generation through van der Waals engineering with two-dimensional materials. We align two van der Waals thin layers perpendicular to each other, yielding polarization-entangled photon pairs through the interference of biphoton emission in the two flakes. The polarization-entangled state is measured with a fidelity up to 86 ± 0.7%. The compatibility of van der Waals engineering with on-chip photonics opens new possibilities for entangled photon source integration at the subwavelength scale.

Sustainability along the battery value chain is a much talked about goal but currently comes third after cost and performance. Historically, improved sustainability comes with a penalty in terms of cost and performance. This interplay will certainly evolve in the coming years. Ecological and social aspects driven by legislative frameworks guarantee recycling of lithium-ion batteries (LIBs) to prevent hazardous waste in landfills. The trend in the electric vehicle (EV) sector towards low-cost chemistries like lithium iron phosphate (LFP) represents a double-edged sword, as the recycling profitability of such materials is extremely low for the established recycling methods. Extending battery lifetime and enabling direct recycling, where anode and cathode materials maintain their structure and functionality, are key strategies to increase sustainability and profitability. However, their implementation necessitates a shift in LIB design priorities. This Perspective highlights design for circularity as an enabler for improved battery longevity and direct recycling and represents a key tipping element for reducing cost and increasing sustainability in LIB production and disposition concurrently. We outline challenges and opportunities in battery production with special focus on the European EV sector and define actions required from various stakeholders along the value chain to overcome the mindset of linear economies.

State-of-the-art organic photovoltaic (OPV) devices are based on Y-type acceptors, with power conversion efficiencies now exceeding 20%. However, the basic structure–photophysics–performance relationship of these materials remains unclear, hindering rational material development and engineering. Here we investigate a broad range of Y-type acceptors using a combination of experimental and theoretical studies. We first show that a transient electroabsorption (TEA) signal is universal in neat Y-type acceptor films upon photoexcitation, which is caused by the formation of intermolecular charge-transfer (ICT) states in tightly packed molecular aggregates (i.e. ordered regions of the film). Tracking the TEA signal growth dynamics can monitor the migration of excitons from disordered to ordered regions in various Y-type acceptor films on the sub-picosecond timescale. Importantly, our results reveal that Y-type acceptors with moderately reduced intermolecular interaction strength can generally achieve faster exciton migration, better structural uniformity and higher device performance, thereby providing insights for future OPV material development and engineering.

Cobalt-based oxides are potential alternatives to noble metal catalysts for the acidic oxygen evolution reaction (OER); however, their activity and stability are limited by the surface reorganization of cobalt oxide into the Co(IV)O active phase of pure Co₃O₄ with retarded OER kinetics. Herein, we report a geometrically reconstructed active site F–Co–O of Co₃O_4−xF_x phase by forming an F electron-dominated sharing effect, which prominently regulates the Co pre-OER feature of the pure Co₃O₄ catalyst, and displays an unconventional electrochemical behavior for remarkably boosted acidic water oxidation. The Co₃O_4−xF_x catalyst exhibits a relatively low overpotential of 349 mV at 10 mA cm⁻² and operation durability of 120 h at 100 mA cm⁻² for the acidic OER, making it one of the best-performing non-noble metal catalysts. The in-depth mechanistic analysis via quasi in situ/operando techniques and density functional theory proves the ability of F to adjust the Co pre-oxidation reaction on Co₃O_4−xF_x and reproduces the remarkable activity of the OER over Co₃O_4−xF_x, as well as detailing the switchable rate-determining step and catalytic mechanisms for exceptionally enhanced performance. This work opens feasible avenues for designing acidic OER catalysts of non-precious metal oxides toward commercial water electrolysis.

Triboelectric nanogenerators (TENGs) show great potential for wave energy harvesting. However, the low frequency and chaotic nature make it difficult for TENGs to generate stable electrical outputs, posing challenges for directly powering electronics and designing universal power management circuits. Inspired by the consistent and steady energy output of octave boxes, we propose a novel energy regularization triboelectric nanogenerator (ER-TENG). Chaotic wave energy is temporarily stored in coil springs by one-way bearings and then converted into a controlled rotation to drive TENGs through the synergistic effect of a gear set and a centrifugal speed limiter. The relationship between the rotational speed and the configuration of the gear set/centrifugal speed limiter is investigated to optimize the mechanical transmission efficiency. Moreover, the utilization of ternary dielectric materials and multi-layer stacked units enhances the electro-mechanical conversion efficiency, resulting in an average power density of up to 15.67 W m⁻³. Fast charging of capacitors is achieved through the ER-TENG using a simple power management circuit. In practical applications, the ER-TENG demonstrates the capability to continuously power offshore appliances. This energy regularization strategy enables TENGs to directly output a stable signal, which serves as a significant reference for the development of smart ocean systems.