We synthesized a series of carbon‐supported atomic metal‐N‐C catalysts (M‐SACs: M=Mn, Fe, Co, Ni, Cu) with similar structural and physicochemical properties to uncover their catalytic activity trends and mechanisms. The peroxymonosulfate (PMS) catalytic activity trends are Fe‐SAC>Co‐SAC>Mn‐SAC>Ni‐SAC>Cu‐SAC, and Fe‐SAC displays the best single‐site kinetic value (1.65×105 min−1 mol−1) compared to the other metal‐N‐C species. First‐principles calculations indicate that the most reasonable reaction pathway for 1O2 production is PMS→OH*→O*→1O2; M‐SACs that exhibit moderate and near‐average Gibbs free energies in each reaction step have a better catalytic activity, which is the key for the outstanding performance of Fe‐SACs. This study gives the atomic‐scale understanding of fundamental catalytic trends and mechanisms of PMS‐assisted reactive oxygen species production via M‐SACs, thus providing guidance for developing M‐SACs for catalytic organic pollutant degradation.

clinical cancer treatments. [1] Though some conventional methods, such as surgery, radiotherapy, and chemotherapy, have been used to treat malignant melanoma in clinics, these methods have exhibited limited treatment efficiencies in inhibiting tumor growth, leading to low patient survival rates. Therefore, more creative and efficient ways are urgently needed to overcome these clinical bottlenecks; for instance, gene therapy, photodynamic therapy (PDT), photothermal therapy, sonodynamic therapy (SDT), and immunotherapy. [2][3][4][5][6] However, due to the diversity, complexity, and heterogeneity of the MM tumor, [7] mono-modal therapy has been found to show limited treatment efficiency for MM tumors. Consequently, searching for integrated therapeutic strategies with multi-modal therapeutics is highly necessary to achieve remarkable antitumor effects. [8][9][10][11][12] The SDT and PDT have been selected as potential clinical methods for treating a wide range of superficial and localized tumors. They utilize the sono-irradiation or photoexcitation to generate highly reactive oxygen species (ROS), such as singlet oxygen ( 1 O 2 ) and hydroxyl radicals (•OH). [13][14][15][16][17] Owing to the temporal and spatial management over the localization of the sound or light, the ROS can be generated precisely in the tumor tissues instead of normal tissue, thus minimizing the side effects. [18][19][20] The unique quantity of deep tissue penetration and little side The diversity, complexity, and heterogeneity of malignant tumor seriously undermine the efficiency of mono-modal treatment. Recently, multi-modal therapeutics with enhanced antitumor efficiencies have attracted increasing attention. However, designing a nanotherapeutic platform with uniform morphology in nanoscale that integrates with efficient chem-/sono-/phototrimodal tumor therapies is still a great challenge. Here, new and facile Pd-single-atom coordinated porphyrin-based polymeric networks as biocatalysts, namely, Pd-Pta/Por, for chem-/sono-/photo-trimodal tumor therapies are designed. The atomic morphology and chemical structure analysis prove that the biocatalyst consists of atomic Pd-N coordination networks with a Pd-N 2 -Cl 2 catalytic center. The characterization of peroxidase-like catalytic activities displays that the Pd-Pta/Por can generate abundant •OH radicals for chemodynamic therapies. The ultrasound irradiation or laser excitation can significantly boost the catalytic production of 1 O 2 by the porphyrin-based sono-/photosensitizers to achieve combined sono-/photodynamic therapies. The superior catalytic production of •OH is further verified by density functional theory calculation. Finally, the corresponding in vitro and in vivo experiments have demonstrated their synergistic chem-/sono-/photo-trimodal antitumor efficacies. It is believed that this study provides new promising single-atom-coordinated polymeric networks with highly efficient biocatalytic sites and synergistic trimodal therapeutic effects, which may inspire many new findings in rea...

oxidation, [3] the oxygen reduction reaction, [4] hydrogen oxidation reaction, [5] and hydrogen evolution reaction (HER). [6] The scarcity and high cost of Pt have necessitated the development of catalytic systems with increased activity, utilization, and durability of Pt atoms. In this respect, the increase of Pt dispersion on supports by downsizing metals to the atomic scale is of significance for maximizing the Pt utilization and consequently increasing the mass activity and turnover frequency (TOF). [7,8] However, in most cases, the electronic properties of the supported Pt atoms are highly dependent on coordination/supporting environments, which have been shown to be crucial for enabling the Pt catalysts with high intrinsic activity. [9] In recent years, abundant efforts have been made to synthesize the atomic Pt catalysts with tailored coordination environments on diverse supports, such as the N/S-doped carbon materials (Pt 1 /NC, [10] PtRuC [11] ), metal oxides (PtCoO, [12] PtFe 2 O 3 [13] ), metal sulfides (PtMoS 2 [14] ), etc. Anchoring Pt atoms by neighboring strong electronegative atoms will lead to a large charge transfer from Pt to coordinated O/N/S atoms, Platinum-based catalysts occupy a pivotal position in diverse catalytic applications in hydrogen chemistry and electrochemistry, for instance, the hydrogen evolution reactions (HER). While adsorbed Pt atoms on supports often cause severe mismatching on electronic structures and HER behaviors from metallic Pt due to the different energy level distribution of electron orbitals.Here, the design of crystalline lattice-confined atomic Pt in metal carbides using the Pt-centered polyoxometalate frameworks with strong PtO-metal covalent bonds is reported. Remarkably, the lattice-confined atomic Pt in the tungsten carbides (Pt doped @WC x , both Pt and W have atomic radii of 1.3 Å) exhibit near-zero valence states and similar electronic structures as metallic Pt, thus delivering matched energy level distributions of the Pt 5d z 2 and H 1s orbitals and similar acidic hydrogen evolution behaviors. In alkaline conditions, the Pt doped @WC x exhibits 40 times greater mass activity (49.5 A mg Pt −1 at η = 150 mV) than the Pt@C because of the favorable water dissociation and H* transport. These findings offer a universal pathway to construct urgently needed atomic-scale catalysts for broad catalytic reactions.

Developing low-cost electrocatalysts for efficient and robust oxygen evolution reaction (OER) is the key for scalable water electrolysis, for instance, NiFebased materials. Decorating NiFe catalysts with other transition metals offers a new path to boost their catalytic activities but often suffers from the low controllability of the electronic structures of the NiFe catalytic centers. Here, we report an interfacial atomsubstitution strategy to synthesize an electrocatalytic oxygen-evolving NiFeV nanofiber to boost the activity of NiFe centers. The electronic structure analyses suggest that the NiFeV nanofiber exhibits abundant high-valence Fe via a charge transfer from Fe to V. The NiFeV nanofiber supported on a carbon cloth shows a low overpotential of 181 mV at 10 mA cm À 2 , along with long-term stability (> 20 h) at 100 mA cm À 2 . The reported substitutional growth strategy offers an effective and new pathway for the design of efficient and durable non-noble metal-based OER catalysts.

MetalN-coordinated centers supported by carbonaceous substrates have emerged as promising artificial metalloenzymes (AMEs) to mimic the biocatalytic effects of their natural counterparts. However, the synthesis of well-defined AMEs that contain different atomic metalN centers but present similar physicochemical and coordination structures remains a substantial challenge. Here, 20 different types of AMEs with similar geometries and welldefined atomic metalN-coordinated centers are synthesized to compare and disclose the catalytic activities, substrate selectivities, kinetics, and reactive oxygen species (ROS) products. Their oxidase (OXD)-, peroxidase (POD)-, and halogen peroxidase (HPO)-mimetic catalytic behaviors are systematically explored. The Fe-AME shows the highest OXD-and HPO-mimetic activities compared to the other AMEs due to its high v max (0.927 × 10 −6 m s −1 ) and low K m (1.070 × 10 −3 m), while the Cu-AME displays the best POD-like performance. Furthermore, theoretical calculation reveals that the ROS-catalytic paths and activities are highly related to the electronic structures of the metal centers. Benefiting from its facile adsorption of H 2 O 2 molecule and lower energy barrier to generating •O 2 − , the Fe-AME displays higher ROS-catalytic performances than the Mn-AME. The engineered AMEs show not only remarkably high ROS-catalytic performances but also provide new guidance toward developing metalN-coordinated biocatalysts for broad application fields.The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adma.202200255.

Electrocatalysts In article number 2206368, Yi Wang, Li Qiu, Yang‐Gang Wang, Chong Cheng, and co‐workers report on engineering crystalline‐lattice‐confined atomic Pt in metal carbides, which exhibits near‐zero valence states, similar electronic structures, and matched hydrogen evolution behaviors as the Pt(111) surface. Remarkably, the Pt‐doped@WCx catalyst delivers 40 times greater mass activity than Pt@C‐20% in alkaline conditions.

The dramatically increasing demands in enzyme-like catalytic biosynthesis and biotherapeutics have promoted thrilling innovations to engineer artificial enzymes (AEs), [1][2][3][4][5][6][7][8] especially the haloperoxidase (HPO)-like AEs that can generate potent reactive oxygen species (ROS), [9][10][11][12] including • OH, • O 2 -, and HClO/HBrO, for antibacterial and antitumor applications. [13][14][15][16][17][18][19][20][21] Despite the fast flourishment of HPO-like AEs, further enhancing their biocatalytic performances is still a confusing black box since their electronic structures of metal centers and ROScatalytic mechanisms remain largely unclear. [22] The grand challenge is to develop new ideas and precise theoretical guidance for the de novo design of HPOlike AEs and clarify the corresponding electronic structures and catalytic behaviors of metal centers. [23,24] In particular, the vanadium oxide (V 2 O 5 ) is one of the most representative nanomaterials that displays HPO-like activities, which shows broad application potentials from killing pathogenic cells to preventing marine biofouling by catalyzing H 2 O 2 to potent ROS. Compared to natural HPO, the V 2 O 5 -based AEs provide a costeffective, stable, and broad reaction condition pathway. However, the currently reported strategies, [25,26] such as size tuning, modification of composition, and crystal facets engineering, present limited effects on further enhancing the biocatalytic performances of V 2 O 5 -based AEs. Pathways that can efficiently augment the intrinsic ROS-catalytic activities of metal centers in V 2 O 5 -based AEs are still missing.In V 2 O 5 -based AEs, the V centers possess depressed d electrons density due to its coordination with neighboring electronegative oxygen atoms, [27,28] which causes the V-d 2 z electrons (this d 2 z orbital is perpendicular to the basal plane) to become more accessible to form head-on-head sigma bonds with O-p z orbital. Therefore, the V centers in V 2 O 5 possess strong interaction with H 2 O 2 and suppressed dissociation of oxygenintermediates, [25] consequently resulting in reduced reaction dynamics. The de novo design of the d electrons of V centers to modulate the adsorption-energy between the H 2 O 2 and metal sites is essential for further enhancing their intrinsic ROS-catalytic activities. [29] One approach to weaken the accessibility of d 2 z electrons of metal centers is the filling of d yz orbitals near Nanomaterials-based artificial enzymes (AEs) have flourished for more than a decade. However, it is still challenging to further enhance their biocatalytic performances due to the limited strategies to tune the electronic structures of active centers. Here, a new path is reported for the de novo design of the d electrons of active centers by modulating the electron transfer in vanadium-based AEs (VO x -AE) via a unique Zn-O-V bridge for efficient reactive oxygen species (ROS)-catalysis. Benefiting from the electron transfer from Zn to V, the V site in VO x -AE exhibits a lower valence state tha...

Exploring high‐efficiency reactive oxygen species (ROS)‐elimination materials is of great importance for combating oxidative stress in diverse diseases, especially stem‐cell‐based biotherapeutics. By mimicking the FeN active centers of natural catalase, here, an innovative concept to design ROS‐elimination artificial biocatalysts with Ru catalytic centers for stem‐cell protection is reported. The experimental studies and theoretical calculations have systematically disclosed the activity merits and structure diversities of different Ru sites when serving as ROS‐elimination artificial biocatalysts. Benefiting from the metallic electronic structures and synergetic effects of multiple sites, the artificial biocatalysts with Ru cluster centers present exceptional ROS‐elimination activity; notably, it shows much higher catalytic efficiency per Ru atom on decomposing H2O2 when compared to the isolated single‐atom Ru sites, which is more efficient than that of the natural antioxidants and recently reported state‐of‐the‐art ROS‐scavenging biocatalysts. The systematic stem‐cell protection studies reveal that the catalase‐like artificial biocatalysts can provide efficient rescue ability for survival, adhesion, and differentiation functions of human mesenchymal stem cells in high ROS level conditions. It is suggested that applying these artificial biocatalysts with Ru cluster centers will offer a new pathway for engineering high‐performance ROS‐scavenging materials in stem‐cell‐based therapeutics and many other ROS‐related diseases.