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Single‐atom nanozymes (SAzymes) with atomically dispersed active sites are potential substitutes for natural enzymes. A systematic study of its multiple functions can in‐depth understand SAzymes's nature, which remains elusive. Here, we develop a novel ultrafast synthesis of sputtered SAzymes by in situ bombarding‐embedding technique. Using this method, sputtered copper (Cu) SAzymes (CuSA) is developed with unreported unique planar Cu‐C3 coordinated configuration. To enhance the tumor‐specific targeting, we employ a bioorthogonal approach to engineer CuSA, denoted as CuSACO. CuSACO not only exhibits minimal off‐target toxicity but also possesses exceptional ultrahigh catalase‐, oxidase‐, peroxidase‐like multienzyme activities, resulting in reactive oxygen species (ROS) storm generation for effective tumor destruction. Surprisingly, CuSACO can release Cu ions in the presence of glutathione (GSH) to induce cuproptosis, enhancing the tumor treatment efficacy. Notably, CuSACO′s remarkable photothermal properties enables precise photothermal therapy (PTT) on tumors. This, combined with nanozyme catalytic activities, cuproptosis and immunotherapy, efficiently inhibiting the growth of orthotopic breast tumors and gliomas, and lung metastasis. Our research highlights the potential of CuSACO as an innovative strategy to utilize multiple mechanism to enhance tumor therapeutic efficacy, broadening the exploration and development of enzyme‐like behavior and physiological mechanism of action of SAzymes. [ABSTRACT FROM AUTHOR]

Single‐atom nanozymes (SAzymes) with atomically dispersed active sites are potential substitutes for natural enzymes. A systematic study of its multiple functions can in‐depth understand SAzymes's nature, which remains elusive. Here, we develop a novel ultrafast synthesis of sputtered SAzymes by in situ bombarding‐embedding technique. Using this method, sputtered copper (Cu) SAzymes (CuSA) is developed with unreported unique planar Cu‐C3 coordinated configuration. To enhance the tumor‐specific targeting, we employ a bioorthogonal approach to engineer CuSA, denoted as CuSACO. CuSACO not only exhibits minimal off‐target toxicity but also possesses exceptional ultrahigh catalase‐, oxidase‐, peroxidase‐like multienzyme activities, resulting in reactive oxygen species (ROS) storm generation for effective tumor destruction. Surprisingly, CuSACO can release Cu ions in the presence of glutathione (GSH) to induce cuproptosis, enhancing the tumor treatment efficacy. Notably, CuSACO′s remarkable photothermal properties enables precise photothermal therapy (PTT) on tumors. This, combined with nanozyme catalytic activities, cuproptosis and immunotherapy, efficiently inhibiting the growth of orthotopic breast tumors and gliomas, and lung metastasis. Our research highlights the potential of CuSACO as an innovative strategy to utilize multiple mechanism to enhance tumor therapeutic efficacy, broadening the exploration and development of enzyme‐like behavior and physiological mechanism of action of SAzymes. [ABSTRACT FROM AUTHOR]

The efficient conversion of CO2 to value‐added products represents one of the most attractive solutions to mitigate climate change and tackle the associated environmental issues. In particular, electrochemical CO2 reduction to fuels and chemicals has garnered tremendous interest over the last decades. Among all products from CO2 reduction, formic acid is considered one of the most economically vital CO2 reduction products. P‐block metals (especially Bi, Sn, In, and Pb) have been extensively investigated and recognized as the most efficient catalytic materials for the CO2 electroreduction to formate. Despite remarkable progress, the future implementation of this technology at the industrial‐scale hinges on the ability to solve remaining roadblocks. In this review, the current research status, challenges, and prospects of p‐block metal‐based catalysts primarily for CO2 electroreduction to formate are comprehensively reviewed. The rational design and nanostructure engineering of these p‐block metal catalysts for the optimization of their electrochemical performances are discussed in detail. Subsequently, the recent progress in the development of state‐of‐the‐art operando characterization techniques together with the design of advanced electrochemical cells to uncover the intrinsic catalysis mechanism is discussed. Lastly, a perspective on future directions including tackling critical challenges to realize its early industrial implementation is presented. [ABSTRACT FROM AUTHOR]

Due to the complex reaction process involving six‐electron transfer, high overpotential and slow kinetic rate of methanol oxidation, the development process of direct methanol fuel cells (DMFC) has been hampered. Herein, a simple one‐step solvent reduction approach was employed to simultaneously reduce metal ions supported on carbon nanotubes and prepared ternary metal alloy nanoparticles supported on carbon nanotubes electrocatalyst (PtRuPd@CNT). Compared with PtRu@CNT binary metal catalyst, the as‐prepared PtRuPd@CNT ternary metal catalyst displayed more outstanding methanol oxidation reaction (MOR) catalytic performance and good CO anti‐poisoning ability. In the case of using 8 M methanol, the MOR performance of PtRuPd@CNT was 1.8 times better than the PtRu@CNT electrocatalyst. The addition of the Pd atom regulates the surface electronic structure of PtRu alloy, and the strong electronic interaction enhances the MOR activity of the PtRu@CNT catalyst. Furthermore, the addition of the Pd atom in the PtRuPd@CNT electrocatalyst also diminishes adsorption of CO intermediate species on the Pt surface, boosting the CO anti‐poisoning ability of the catalyst and improving the stability. Therefore, the PtRuPd@CNT electrocatalyst incorporating the Pd atoms could actualize the practical application prospect as an efficient concentrated DMFC anode catalyst. [ABSTRACT FROM AUTHOR]

Layered metallic transition-metal dichalcogenides (TMDCs) are ideal platforms for exploring their fascinating electronic properties at two-dimensional limits, such as their charge density wave (CDW) and superconductivity. Therefore, developing ways to improve the crystallization quality of TMDCs is urgently needed. Here we report superconductively tunable NbSe2 grown by a two-step vapor deposition method. By optimizing the sputtering conditions, superconducting NbSe2 films were prepared from highly crystalline Nb films. The bilayer NbSe2 films showed a superconducting transition temperature that was up to 3.1 K. Similar to the salt-assisted chemical vapor deposition (CVD) method, superconducting monolayer NbSe2 crystals were also grown from a selenide precursor, and the growth strategy is suitable for many other TMDCs. Our growth method not only provides a way to improve the crystalline quality of TMDC films, but also gives new insight into the growth of monolayer TMDCs. It holds promise for exploring two-dimensional TMDCs in fundamental research and device applications. [ABSTRACT FROM AUTHOR]

Low-coordinated single atom catalysts compared to M-N4 are appealing in optimized electronic structure for CO2 electro-reduction, but the preparation is still very challenging. Herein, a novel single Ni atom catalyst with Ni-N1-C3 configuration is in-situ evolved on curved carbon nanotubes. The obtained Ni-N1-C3 catalyst exhibits a superior CO Faradaic efficiency of 97% and turnover frequency of 2,890 h−1 at −0.9 V versus the reversible hydrogen electrode, as well as long-term stability over 45 h. High current densities exceeding 200 mA·cm−2 and CO Faradaic efficiency of 99% are achieved in flow-cell. Moreover, in-situ potential-and time-dependent Raman spectra identify the key intermediates of *COOH and *CO during CO2-to-CO conversion. Theoretical calculations reveal that the upward-shifted d-band center and charge-rich Ni sites of Ni-N1-C3 facilitate the electron transfer to *COOH and thus reduce the *COOH formation energy barrier. This work demonstrates a strategy for modulating the coordination environment for efficient CO2 reduction. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of carbon dioxide (CO2) to ethanol is a promising strategy for global warming mitigation and resource utilization. However, due to the intricacy of C─C coupling and multiple proton–electron transfers, CO2‐to‐ethanol conversion remains a great challenge with low activity and selectivity. Herein, it is reported a P‐doped graphene aerogel as a self‐supporting electrocatalyst for CO2 reduction to ethanol. High ethanol Faradaic efficiency (FE) of 48.7% and long stability of 70 h are achieved at −0.8 VRHE. Meanwhile, an outstanding ethanol yield of 14.62 µmol h−1 cm−2 can be obtained, outperforming most reported electrocatalysts. In situ Raman spectra indicate the important role of adsorbed *CO intermediates in CO2‐to‐ethanol conversion. Furthermore, the possible active sites and optimal pathway for ethanol formation are revealed by density functional theory calculations. The graphene zigzag edges with P doping enhance the adsorption of *CO intermediate and increase the coverage of *CO on the catalyst surface, which facilitates the *CO dimerization and boosts the EtOH formation. In addition, the hierarchical pore structure of P‐doped graphene aerogels exposes abundant active sites and facilitates mass/charge transfer. This work provides inventive insight into designing metal‐free catalysts for liquid products from CO2 electroreduction. [ABSTRACT FROM AUTHOR]

Electroreduction of N2 to NH3 at ambient conditions using renewable electricity is promising, but developing efficient electrocatalysts is still challenging due to the inertness of N≡N bonds. Layer double hydroxides (LDHs) composed of first‐row transition metals with empty d‐orbitals are theoretically promising for N2 electroreduction (NRR) but rarely reported. Herein, hollow NiCo‐LDH nanocages with different Ni/Co ratios were prepared, and their electronic structures and atomic arrangements were critical. The synergetic mechanisms of Ni and Co ions were revealed, and the optimized catalytic sites were proposed. Besides, in‐situ Raman spectroscopy and 15N2 isotopic labeling studies were applied to detect reaction intermediates and confirm the origin of NH3. As a result, high NH3 yield of 52.8 μg h−1 mgcat−1 and faradaic efficiency of 11.5 % were obtained at −0.7 V, which are top‐ranking among Co/Ni‐based NRR electrocatalysts. This work elucidates the structure–activity relationship between LDHs and NRR and is instructive for rational design of LDH‐based electrocatalysts. [ABSTRACT FROM AUTHOR]

Facilely tailored electrocatalyst with high-efficiency and durability for carbon dioxide (CO2) to carbon monoxide (CO) conversion is appealing but remains challenging. Herein, small nickel nanoparticles (about 19.4 nm) confined in nitrogen-doped carbon (Ni NPs@N–C) with narrow size distribution are successfully constructed via a facile one-step calcination strategy of Ni containing MOF compounds. By virtue of the protective N-doped graphitized carbon shell and the uniformly distributed fine Ni nanoparticles in a narrow range from 13 to 21 nm, the as-obtained Ni NPs@N–C can exclusively convert CO2 into CO with excellent Faradaic efficiency (FE) of 96.8% at − 1.0 V (vs. RHE), as well as the superior long-term catalytic stability over 24 h. Moreover, a high current density of more than 200 mA cm−2 with a stable CO FE of 92% can be achieved in a flow cell configuration. This work paves a new way for the facile and potentially scale preparation of small metal nanoparticles for efficient CO2- to-CO conversion. [ABSTRACT FROM AUTHOR]

The ability to manipulate the binding strengths of intermediates on a catalyst is extremely challenging but essential for active and selective CO2 electroreduction (CO2RR). Single-atom copper anchored on a nitrogenated carbon (Cu–N–C) structure is still rarely unexplored for efficient CO production. Herein, we demonstrate a plausible hydrogen-bonding promoted strategy that significantly enhances the *COOH adsorption and facilitates the *CO desorption on a Cu–N–C catalyst. The as-prepared Cu–N–C catalyst with Cu–N3 coordination achieves a high CO faradaic efficiency (FE) of 98% at −0.67 V (vs. reversible hydrogen electrode) as well as superior stability (FE remains above 90% over 20 h). Notably, in a three-phase flow cell configuration, a remarkable CO2 to CO FE of 99% at −0.67 V accompanying a large CO partial current density of 131.1 mA cm−2 at −1.17 V was observed. Density functional theory calculations reveal that the Cu–N3 coordination is potentially stabilized by an extended carbon plane with six nitrogen vacancies, while three unoccupied N sites are spontaneously saturated by protons during the CO2RR. Therefore, the hydrogen bonds formed between the adsorbed *COOH and adjacent protons significantly reduce the energy barrier of *COOH formation. After the first proton-coupled electron transfer process, the adsorbed *CO species are easily released to boost the CO production. [ABSTRACT FROM AUTHOR]

Earth-abundant elements are highly desirable electrocatalysts for artificial N2 fixation (NRR). However, most earth-abundant elements are inactive for the NRR, and the competitive hydrogen evolution reaction (HER) causes inferior faradaic efficiency. Thus, facile modification methods to transform an NRR-unfavorable electrocatalyst into its NRR-favorable counterpart are highly demanded. Herein, we present an efficient hydrophobic carbon layer incorporation strategy on tin monosulfide (SnS@C) to greatly boost the NRR activity of SnS. The hydrophobic carbon layer can limit proton availability at the electrode surface while integrating the advantages of strong N2 adsorption and better conductivity that synergistically improve the NRR performance. Specifically, SnS@C delivers a high faradaic efficiency of 14.56% and NH3 yield of 7.95 × 10−11 mol s−1 cm−2 (24.33 μgNH3 h−1 mgcat−1) at −0.5 V versus the reversible hydrogen electrode. It also exhibits durable stability for consecutive electrolysis over 18 h. Adequate control and 15N isotopic labeling experiments confirm the reliability of N sources. Density functional theory calculations reveal that the superior activity is attributed to the redistribution and bias of electrons between the SnS and carbon-layer interface. This work highlights that the simple hydrophobic carbon layer incorporation strategy could guide the design and modification of advanced NRR catalysts. [ABSTRACT FROM AUTHOR]

This paper presents a compact high-temperature superconducting (HTS) diplexer using single-resonance and dual-resonance spiral resonators. The single-resonance spiral resonators (SSRs) are used separately in each individual channel of the diplexer, and the dual-resonance spiral resonators (DSRs) are used as common resonators of both channels. DSRs are designed using a modified stub-loaded resonator, which can produce two resonant frequencies for both the channels of the diplexer. Because the SSRs and the DSRs are dissimilar resonators, their different spurious frequencies result in a wide stopband. Moreover, resonators are connected by a novel coupling diagram to ensure both high performance and compact size. The size of the diplexer can be greatly reduced while the isolation is kept well. Based on the method, a diplexer is designed for 1.8-GHz mobile and 2.4-GHz wireless area networks systems. The diplexer is fabricated on a YBa2Cu3Oy polished MgO substrate wafer, which has a compact size of $0.12~\lambda g \times 0.073~\lambda g$ . The measured frequency responses agree well with the simulated results. The isolations in both channels are larger than 39 dB, and the measured insertion losses of both channels are less than 0.41 dB. [ABSTRACT FROM AUTHOR]

A novel compact microstrip diplexer for UMTS and WCDMA system is proposed in this letter. The diplexer is mainly composed of three dual-mode stub-loaded microstrip resonators. Two resonant modes of a stub-loaded resonator work together with one mode produced by the common stub-loaded resonator to form a passband or operating band of the proposed diplexer. Extensive study is then conducted on coupling scheme involved in various parts of the diplexer. In particular, the resonance of a resonator is employed to create a desired transmission zero in the stopband, thus improving the isolation between two passbands. The proposed diplexer is in final fabricated and measured. A good agreement between EM simulated and measured results evidently validates the proposed methodology. [ABSTRACT FROM PUBLISHER]