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The utilization of CO2 has become an emerging area of research in response to climate change and global warming. The electrochemical CO2 reduction reaction (CO2RR) holds significant promise as a technology to address this issue by converting CO2 molecules into various commercially valuable chemicals. While CO2RR to C1 hydrocarbons has achieved high activity and selectivity, the C–C coupling to produce higher hydrocarbons remains challenging due to low energy efficiency and the prevalent hydrogen evolution reaction (HER) on the same catalyst, leading to high hydrogenation rates. In this review, we aim to elucidate the fundamental challenges of C–C coupling and explore potential strategies to enhance the selectivity for higher hydrocarbon products. We discuss the mechanisms underlying the formation of C2 and C3 products, focusing on molecular catalysts that facilitate C–C coupling by positioning CO2 molecules in close proximity. Additionally, we provide a comprehensive overview of different approaches to improve higher hydrocarbon selectivity, along with future suggestions and recommendations for new researchers in the field. This review serves as a valuable resource for both academic researchers and industrial stakeholders aiming for the commercialization of CO2RR technologies. [ABSTRACT FROM AUTHOR]

Aqueous ammonium‐ion batteries (AIBs) are considered a promising alternative for large‐scale energy storage due to their cost‐effectiveness and high safety. Prussian blue analogues (PBAs) are widely regarded as potential cathode materials for AIBs because of their high working potential and stable 3D framework. However, the low capacity of PBAs (≈60 mAh g−1 in the existing reported works) hinders their further development. Herein, the ion insertion is first proposed to double the capacity of PBAs by unlocking the inert‐site. Using NH4+‐rich copper hexacyanoferrate as a representative, trace amounts of induced ion in the electrolyte can change the electronic states of atoms at the inert site to achieve much higher capacity. What's more, the construction of NH4+‐rich high‐entropy Prussian blue (N‐HEPBA) further facilitates structural stability. N‐HEPBA unlocked by corresponding induced ions can exhibit an impressive specific capacity (129 mAh g−1 at 0.1 A g−1), which is the highest and approximately twice that of reported PBAs for aqueous AIBs. Meanwhile, it delivers excellent cycling stability with nearly 100% capacity retention achieved over 1000 cycles at 2 A g−1. This innovative unlocking method can provide an effective way to obtain high‐capacity PBAs in AIBs, thus promoting the development of large‐scale energy storage. [ABSTRACT FROM AUTHOR]

The oxygen reduction reaction (ORR) is a crucial cathode reaction for developing quasi‐solid zinc–air batteries (QZABs) with high energy density. However, the activity and stability of catalysts under extreme conditions have not been fully explore. Herein, a series of systematic experiments and theoretical calculations have been conducted to investigate the potential of introducing FexCoy into nitrogen (N)‐doped porous carbon (NPC) via one‐step pyrolysis to form a core–shell structure that can effectively enhance the activity of the catalysts, particularly at low temperatures. Due to the difference in the work function of 5.12, 5.11, and 5.06 eV, the spin‐polarized charge is transferred to the pyridinic‐N site on the surface under the charge transfer. Consequently, the pyridinic‐N site on the surface exhibits varying degrees of magnetic moment 0.024 µB, which is crucial for forming OOH* and enhances ORR activity. The Fe5Co5@NPC catalyst is evaluated for QZABs at −40 °C and achieved a power density of up to 117.6 mW cm−2, which is only 18.7% lower than normal temperature, and a cycle life of up to 300 h. This study provides a means to realize the design of QZABs catalysts in extreme environments and explore their application potential. [ABSTRACT FROM AUTHOR]

Electron spin polarization (ESP) refers to the alignment of electron spins in a specified direction, with burgeoning research underscoring its pivotal role in enhancing rechargeable batteries. This review delves into the theoretical underpinnings of ESP and its intricate connection to the performance of rechargeable batteries, elucidating its potential to augment charge/discharge efficiency, elevate energy density, and refine overall battery functionality. The review further encompasses an overview of experimental methodologies employed to probe ESP in rechargeable battery systems, spotlighting seminal discoveries from contemporary studies and evaluating the hurdles and prospects linked to its practical applications. The profound advantages of ESP for rechargeable batteries are underscored, suggesting that harnessing this phenomenon can empower researchers and engineers to develop batteries with superior energy storage capacities, swifter charging rates, and extended cycle lifespans. Such advancements can expedite the adoption of electric vehicles and the seamless integration of renewable energy sources into power grids, among other high‐energy‐demand applications. In conclusion, this review offers invaluable perspectives on rechargeable batteries through the lens of ESP, with the insights presented here expected to catalyze further research and innovation in the energy storage sector, thereby advancing the development of sustainable and efficient rechargeable battery technologies. [ABSTRACT FROM AUTHOR]

Carbon-based nanomaterials are gaining attention in electrocatalysis. This study investigates the inherent nitrate reduction activity (NO3RR) of commercial carbon paper as a substrate. Results showed that carbon paper, without additional catalysts, achieved approximately 80.42% NH3 Faradaic efficiency (FE) at -2.1 V vs. Hg/HgO in alkaline conditions, 83.51% NH3 FE at -1.9 V vs. Ag/AgCl in neutral conditions, and 14.53% NH3 FE at -1.9 V vs. MSE in acidic conditions. Density Functional Theory (DFT) calculations revealed energy barriers of 2.66 eV, 0.95 eV, and 1.37 eV, respectively. Molecular physisorption on the carbon paper surface generates an induced electric field, promoting charge transfer between the carbon paper and the adsorbed molecules, thus enhancing the activity of the carbon paper. These findings highlight the importance of considering the intrinsic catalytic properties of carbon substrates in catalyst design and evaluation, as overlooking these properties can lead to inaccurate performance assessments. This study emphasizes the need for a comprehensive approach to optimize catalytic systems., (© 2024 Wiley‐VCH GmbH.)

The utilization of CO 2 has become an emerging area of research in response to climate change and global warming. The electrochemical CO 2 reduction reaction (CO 2 RR) holds significant promise as a technology to address this issue by converting CO 2 molecules into various commercially valuable chemicals. While CO 2 RR to C 1 hydrocarbons has achieved high activity and selectivity, the C-C coupling to produce higher hydrocarbons remains challenging due to low energy efficiency and the prevalent hydrogen evolution reaction (HER) on the same catalyst, leading to high hydrogenation rates. In this review, we aim to elucidate the fundamental challenges of C-C coupling and explore potential strategies to enhance the selectivity for higher hydrocarbon products. We discuss the mechanisms underlying the formation of C 2 and C 3 products, focusing on molecular catalysts that facilitate C-C coupling by positioning CO 2 molecules in close proximity. Additionally, we provide a comprehensive overview of different approaches to improve higher hydrocarbon selectivity, along with future suggestions and recommendations for new researchers in the field. This review serves as a valuable resource for both academic researchers and industrial stakeholders aiming for the commercialization of CO 2 RR technologies.

Despite the immense potential of Dual Single-Atom Compounds (DSACs), the challenges in their synthesis process, including complexity, stability, purity, and scalability, remain primary concerns in current research. Here, we present a general strategy, termed "Entropy-Engineered Middle-In Synthesis of Dual Single-Atom Compounds" (EEMIS-DSAC), which is meticulously crafted to produce a diverse range of DSACs, effectively addressing the aforementioned issues. Our strategy integrates the advantages of both bottom-up and top-down paradigms, proposing an insight into optimizing the catalyst structure. The as-fabricated DSACs exhibited excellent activity and stability in the nitrate reduction reaction (NO 3 RR). In a significant advancement, our prototypical CuNi DSACs demonstrated outstanding performance under conditions reminiscent of industrial wastewater. Specifically, under a NO 3 - concentration of 2000 ppm, it yielded a Faradaic efficiency (FE) for NH 3 of 96.97%, coupled with a mass productivity of 131.47 mg h -1 mg -1 and an area productivity of 10.06 mg h -1 cm -2 . Impressively, even under a heightened NO 3 - concentration of 0.5 M, the FE for NH 3 peaked at 90.61%, with a mass productivity reaching 1024.50 mg h -1 mg -1 and an area productivity of 78.41 mg h -1 cm -2 . This work underpins the potential of the EEMIS-DSAC approach, signaling a frontier for high-performing DSACs.

Downsizing silicon-based transistors can result in lower power consumption, faster speeds, and greater computational capacity, although it is accompanied by the appearance of short-channel effects. The integration of high-mobility 2D semiconductor channels with ultrathin high dielectric constant (high-κ) dielectric in transistors is expected to suppress the effect. Nevertheless, the absence of a high-κ dielectric layer featuring an atomically smooth surface devoid of dangling bonds poses a significant obstacle in the advancement of 2D electronics. Here, ultrathin van der Waals (vdW) lanthanum oxychloride (LaOCl) dielectrics are successfully synthesized by precisely controlling the growth kinetics. These dielectrics demonstrate an impressive high-κ value of 10.8 and exhibit a remarkable breakdown field strength (E bd ) exceeding 10 MV cm -1 . Remarkably, the conventional molybdenum disulfide (MoS 2 ) field-effect transistor (FET) featuring a dielectric made of LaOCl showcases an almost negligible hysteresis when compared to FETs employing alternative gate dielectrics. This can be attributed to the flawlessly formed vdW interface and excellent compatibility established between LaOCl and MoS 2 . These findings will motivate the further exploration of rare-earth oxychlorides and the development of more-than-Moore nanoelectronic devices., (© 2023 Wiley-VCH GmbH.)

MXenes, two-dimensional nanomaterials, are gaining traction in catalysis and biomedicine. Yet, their oxidation instability poses significant functional constraints. Gaining insight into this oxidation dynamic is pivotal for designing MXenes with tailored functionalities. Herein, we crafted VO x C nanosheets by oxidatively engineering V 4 C 3 MXene. Interestingly, while pristine V 4 C 3 displays pronounced antioxidant behavior, its derived VO x C showcases enhanced peroxidase-like activity, suggesting the crossover between antioxidant and pro-oxidant capability. The mixed valence states and balanced composition of V in VO x C drive the Fenton reaction through multiple pathways to continually generate hydroxyl radicals, which was proposed as the mechanism underlying the peroxidase-like activity. Furthermore, this unique activity rendered VO x C effective in dopamine and glutathione detection. These findings underscore the potential of modulating MXenes' oxidation state to elicit varied catalytic attributes, providing an avenue for the judicious design of MXenes and derivatives for bespoke applications., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

2D room-temperature magnetic materials are of great importance in future spintronic devices while only very few are reported. Herein, a plasma-enhanced chemical vapor deposition approach is exploited to construct the 2D room-temperature magnetic MnGa 4 -H single crystal with a thickness down to 2.2 nm. The employment of H 2 plasma makes hydrogen atoms can be easily inserted into the MnGa 4 lattice to modulate the atomic distance and charge state, thereby ferrimagnetism can be achieved without destroying the structural configuration. The as-obtained 2D MnGa 4 -H crystal is high-quality, air-stable, and thermo-stable, demonstrating robust and stable room-temperature magnetism with a high Curie temperature above 620 K. This work enriches the 2D room-temperature magnetic family and opens up the possibility for the development of spintronic devices based on 2D magnetic alloys., (© 2023 Wiley-VCH GmbH.)