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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]

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]

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]

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]

Nanozyme catalytic therapy triggered by the tumor microenvironment (TME)-responsive enzyme-like catalytic activities is an emerging approach for tumor treatment. However, the poor catalytic efficiency of nanozymes in tumors and the toxic side effects on normal tissues limit their further development, primarily due to the limited uptake and penetration depth of nanozyme in tumor tissues. Here, a tumor-targeting TME and electric field stimuli-responsive nanozyme (AgPt@CaCO 3 -FA) is developed, which is capable of catalyzing the generation of ROS to induce cell death and releasing carbon monoxide (CO) specifically in tumor tissues for on-demand CO therapy and immunotherapy. Benefiting from the endogenous H 2 S activated NIR-II fluorescence (FL) imaging guidance, AgPt@CaCO 3 -FA can be delivered into the deeper site of tumor tissues resulted from the TME regulation via generated CO during the electrolysis process to improve the catalytic efficiency of nanozymes in tumors. Moreover, CO effectively relieve immunosuppression TME via reeducating tumor-supportive M2-like macrophages to tumoricidal M1-like macrophages and induce mitochondrial dysfunction by reducing mitochondrial membrane potential, triggering tumor cells apoptosis. The enzyme-like activities combined with CO therapy arouse distinct immunogenic cell death (ICD) effect. Therefore, AgPt@CaCO 3 -FA permits synergistic CO gas, catalytic therapy and immunotherapy, effectively eradicating orthotopic breast tumors and preventing tumor metastasis and recurrence., (© 2024 Wiley‐VCH GmbH.)

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-C 3 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., (© 2024 Wiley-VCH GmbH.)

Electrochemical reduction of carbon dioxide (CO 2 ) 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, CO 2 -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 CO 2 reduction to ethanol. High ethanol Faradaic efficiency (FE) of 48.7% and long stability of 70 h are achieved at -0.8 V RHE . 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 CO 2 -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 CO 2 electroreduction., (© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.)