Due to integrated advantages in electrochemical functionalities for energy conversion, 2D nonlayered heterostructure nanosheets offer new and fascinating opportunities for electrocatalysis but their fabrication is challenging when compared with the widely studied 2D layered heterostructure. Herein, a bottom‐up approach is established for facile synthesis of holey 2D transition metal carbide/nitride heterostructure nanosheets (h‐TMCN) with regulated hole sizes by controlled thermal annealing of the Mo/Zn bimetallic imidazolate frameworks (Mo/Zn BIFs). Ex situ phase and structural identifications disclose that the Mo/Zn BIFs precursor experiences interconnected three steps of transformation to produce h‐TMCN. Especially, the slow successive solid‐state diffusion of nitrogen and carbon into immediate noncrystalline molybdenum oxides allows the intergrowth of Mo2C and Mo2N into the 2D nonlayered heterostructure. X‐ray fine structure analysis coupled with high resolution X‐ray photoelectron spectroscopy demonstrate that Mo2C and Mo2N in the microdomains can chemically bond with each other, producing the abundant active N–Mo–C interfaces toward water splitting. Consequently, h‐TMCN affords low overpotentials, high turnover frequencies, rapid charge transfer, and superior long‐term stability toward electrocatalytic water oxidation. The present work demonstrates the feasibility of developing a broad range of 2D nonlayered heterostructures for high efficiency chemical energy conversion.

We demonstrate the stabilization of the localized surface plasmon resonance (LSPR) in a semiconductor-based core–shell heterostructure made of a plasmonic CuS core embedded in an amorphous-like alloyed CuPdxS shell. This heterostructure is prepared by reacting the as-synthesized CuS nanocrystals (NCs) with Pd2+ cations at room temperature in the presence of an electron donor (ascorbic acid). The reaction starts from the surface of the CuS NCs and proceeds toward the center, causing reorganization of the initial lattice and amorphization of the covellite structure. According to density functional calculations, Pd atoms are preferentially accommodated between the bilayer formed by the S–S covalent bonds, which are therefore broken, and this can be understood as the first step leading to amorphization of the particles upon insertion of the Pd2+ ions. The position and intensity in near-infrared LSPRs can be tuned by altering the thickness of the shell and are in agreement with the theoretical optical simulation based on the Mie–Gans theory and Drude model. Compared to the starting CuS NCs, the amorphous CuPdxS shell in the core–shell nanoparticles makes their plasmonic response less sensitive to a harsh oxidation environment (generated, for example, by the presence of I2).

Zeolitic imidazolate frameworks (ZIFs) are a rapidly emerging class of versatile porous material with many potential applications. Here, we report the construction of an amorphous ZIF (a-ZIF) model from a near-perfect continuous random network model of a-SiO 2 . The radial distribution function is in good agreement with measurements for amorphous a T ZIF-4 but with notable fine differences. The electronic structure and properties of a-ZIF model are critically compared with three crystalline ZIF phases: ZIF-4, ZIF-zni, and ZIF-8 using density functional theory methods. We confirm the retention of the metal tetrahedral bonding coordination in a-ZIF and the nearly identical short range ordering found in crystalline ZIFs. The considerable Zn-N bond strength plays a key role in retaining the tetrahedrally bonded network structure. The calculated optical properties of a-ZIF show a complex absorption spectrum with an ultralow refractive index n of 1.327 and a plasmon frequency of 15.810 eV.

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Electrochemical reduction of O 2 to produce H 2 O 2 provides the most promising alternative to the current anthraquinone process, whereas an electrocatalyst that is costeffective and has rich resources, excellent oxygen reduction reaction (ORR) activity, and dominant two-electron (2e − ) selectivity is highly required. Herein, by using inexpensive and earth-abundant anthracite coal as the precursor along with the KOH activation method, a defective graphene-like carbon (DGLC) nanomaterial has been successfully constructed. The as-prepared DGLC material features a graphene-like morphology, a hierarchical porous structure, a high surface area, abundant defects/edges, and a high content of ether functional groups, which endow it with excellent ORR activity, dominant 2e − selectivity, and high stability toward H 2 O 2 synthesis in alkaline media. Remarkably, when employed as the electrocatalyst in H-cell, it can achieve a high H 2 O 2 production rate of 355.0 mmol L −1 h −1 cm −2 g cat −1 with nearly 100% Faraday efficiency, which is superior to most carbon-based ORR catalysts. Experimental and theoretical studies describe that such high ORR activity and selectivity of DGLC are highly associated with its defect degree and ether groups (C−O−C) content, respectively, which contribute together to boost the superior 2e − ORR performance. This finding will be very helpful for designing a carbon-based 2e − ORR electrocatalyst toward H 2 O 2 synthesis.

Metal-free carbon-based materials are considered one of the most promising two-electron oxygen reduction reaction (2e– ORR) electrocatalysts for the green synthesis of hydrogen peroxide (H2O2). However, most reported carbon electrocatalysts perform much more effectively in alkalis than in acids. Herein, by creatively using fullerene (C60) as the precursor subject to ammonia treatment, we designed and synthesized a pentagonal defect-rich nitrogen-doped carbon nanomaterial (PD/N–C). It achieves outstanding ORR activity, 2e– selectivity, and stability in acidic electrolytes, surpassing the benchmark PtHg4 alloy catalyst. Impressively, the flow cell based on the PD/N–C catalyst achieves nearly 100% Faraday efficiency with a remarkable H2O2 yield, representing the best improvement among all the metal-free catalysts. Experimental and theoretical results reveal that such superb 2e– ORR performance of PD/N–C originates from the synergism between pentagonal defects and nitrogen dopants. This work presents an effective strategy for the design and construction of highly efficient acid-resistant carbon electrocatalysts for H2O2 production and beyond.