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The water‐soluble salt‐template technique holds great promise for fabricating 3D porous materials. However, an equipment‐free and pore‐size controllable synthetic approach employing salt‐template precursors at room temperature has remained unexplored. Herein, we introduce a green room‐temperature antisolvent precipitation strategy for creating salt‐template self‐assembly precursors to universally produce 3D porous materials with controllable pore size. Through a combination of theoretical simulations and advanced characterization techniques, we unveil the antisolvent precipitation mechanism and provide guidelines for selecting raw materials and controlling the size of precipitated salt. Following the calcination and washing steps, we achieve large‐scale and universal production of 3D porous materials and the recycling of the salt templates and antisolvents. The optimized nitrogen‐doped 3D porous carbon (N‐3DPC) materials demonstrate distinctive structural benefits, facilitating a high capacity for potassium‐ion storage along with exceptional reversibility. This is further supported by in situ electrochemical impedance spectra, in situ Raman spectroscopy, and theoretical calculations. The anode shows a high rate capacity of 181 mAh g−1 at 4 A g−1 in the full cell. This study addresses the knowledge gap concerning the room‐temperature synthesis of salt‐template self‐assembly precursors for the large‐scale production of porous materials, thereby expanding their potential applications for electrochemical energy conversion and storage. [ABSTRACT FROM AUTHOR]

Changing the composition is an important way to regulate the electrocatalytic performance of the oxygen evolution reaction (OER) for metallic compounds. Clarifying the synergistic mechanism among different compositions is a key scientific problem to be solved urgently. Here, based on first-principles calculations, a Ni–O–Fe multisite dynamic synergistic reaction mechanism (MDSM) for the OER of Fe-doped NiOOH (NiFeOOH) has been discovered. Based on the MDSM, Fe/O/Ni are triggered as the active sites in turn, resulting in an overpotential of 0.33 V. The factors affecting the deprotonation, O–O coupling, and O2 desorption during the OER process are analyzed. The electron channels related to the magnetic states among Fe–O–Ni is revealed, which results in the decoupling between OER sites and the oxidation reaction sites. O–O coupling and O2 desorption are affected by ferromagnetic coupling and the instability of the lattice O during the OER process, respectively. The results give a comprehensive understanding of the active sites in NiFeOOH and provide a new perspective on the synergistic effects among different compositions in metal compounds during the OER process. [ABSTRACT FROM AUTHOR]

To support the global goal of carbon neutrality, numerous efforts have been devoted to the advancement of electrochemical energy conversion (EEC) and electrochemical energy storage (EES) technologies. For these technologies, transition metal dichalcogenide/carbon (TMDC/C) heterostructures have emerged as promising candidates for both electrode materials and electrocatalysts over the past decade, due to their complementary advantages. It is worth noting that interfacial properties play a crucial role in establishing the overall electrochemical characteristics of TMDC/C heterostructures. However, despite the significant scientific contribution in this area, a systematic understanding of TMDC/C heterostructures' interfacial engineering is currently lacking. This literature review aims to focus on three types of interfacial engineering, namely interfacial orientation engineering, interfacial stacking engineering, and interfacial doping engineering, of TMDC/C heterostructures for their potential applications in EES and EEC devices. To accomplish this goal, a combination of experimental and theoretical approaches was used to allow the analysis and summary of the fundamental electrochemical properties and preparation strategies of TMDC/C heterostructures. Moreover, this review highlights the design and utilization of the interfacial engineering of TMDC/C heterostructures for specific EES and EEC devices. Finally, the challenges and opportunities of using interfacial engineering of TMDC/C heterostructures in practical EES and EEC devices are outlined. We expect that this review will effectively guide readers in their understanding, design, and application of interfacial engineering of TMDC/C heterostructures. [ABSTRACT FROM AUTHOR]