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Jiang, Wei; He, Dayin; Ma, Xianhui; Zhou, Huang; Wu, Yuen

doi: 10.1002/smll.202504360pmid: 40289442

Acetylene (C2H2), a critical chemical feedstock derived from natural gas or coal, faces sustainability challenges due to high CO₂ emissions from conventional production methods. These emissions not only contribute to carbon footprints but also hinder the upgrading of C2H2. Herein, a two‐step electrochemical and thermochemical cascade system that directly converts CO₂‐contaminated crude acetylene into C6+ esters is proposed. In the first step, CO₂ from crude acetylene is captured by hydroxide to form bicarbonate, which is subsequently released in situ at the cathode under electrolysis. Using a Ni single‐atom catalyst, CO is efficiently generated with a Faradaic efficiency of 97.8 ± 0.84% at 100 mA cm−2. The generated CO then reacts with acetylene in the second step, where a Pd‐based catalyst enables the production of dimethyl butenedioate at 7.83 ± 0.31 mmol L−1 h−1 and selective dimethyl maleate synthesis (>65% selectivity). Furthermore, replacing methanol with ethanol or butanol in the carbonylation step allows for tunable synthesis of diethyl or dibutyl butenedioate, demonstrating broad applicability. Techno‐economic analysis indicates a 46.9% cost reduction compared to the traditional reverse water‐gas shift system, attributed to lower energy demands and eliminated separation steps. This work provides a green strategy for valorizing low‐value acetylene streams while mitigating CO₂ emissions.

Zhou, Boran; Liu, Kaiyuan; Yu, Kedi; Zhou, Qiang; Gao, Yan; Gao, Xin; Chen, Zhengbo; Chen, Wenxing; Chen, Pengwan

doi: 10.1002/smll.202501917pmid: 40237142

A recent development in catalytic research, single‐atom catalysts (SACs) are one of the most significant categories of catalytic materials. During preparation, individual atoms migrate and agglomerate due to the high surface free energy. The rapid thermal shock strategy addresses this challenge by employing instantaneous high‐temperature pulses to synthesize SACs, while minimizing heating duration to prevent metal aggregation and substrate degradation, thereby preserving atomic‐level dispersion. The resultant SACs exhibit exceptional catalytic activity, remarkable selectivity, and long‐term stability, which have attracted extensive attention in electrocatalysis. In this paper, cutting‐edge ultrafast synthesis techniques such as Joule heating, microwave radiation, pulsed discharge, and arc discharge are comprehensively analyzed. Their ability is emphasized to achieve uniform dispersion of separated metal atoms and optimize the catalytic activity for electrocatalytic applications. A systematic summary of SACs synthesized by these rapid methods is provided, with particular emphasis on their implementation in carbon dioxide reduction reaction (CO2RR), oxygen evolution reaction (OER), hydrogen evolution reaction (HER), and oxygen reduction reaction (ORR) systems. The review provides an in‐depth discussion on the rapid synthesis strategy for development trend, remaining challenges, and the application prospects in electrocatalysis.

Tu, Meilian; Zhu, Zhixiao; Yang, Hao; Balogun, M.‐Sadeeq; Huang, Yongchao; Tong, Yexiang

doi: 10.1002/smll.202502063pmid: 40256845

Electrochemical water splitting is a promising approach for sustainable hydrogen production, but the oxygen evolution reaction (OER) remains a bottleneck due to sluggish kinetics, poor activity, and limited stability and scalability. Here, a Mo2N‐functionalized nickel is designed foam (NF@Mo2N) and subsequently transform into a Mo2N/NiSe/Ni2P multi‐phase heterostructure through selenization and phosphorization, to address these challenges. The optimized NF@Mo2N/NiSe/Ni2P catalyst integrates three key strategies: (I) functionalizing NF with Mo2N to enhance conductivity and charge transfer, (II) engineering a collaborative multi‐interface heterostructure to optimize active sites and reaction kinetics, and (III) precisely controlling phase formation through selenization and phosphorization to mitigate surface reconstruction and ensure long‐term stability. The catalyst not only achieves an overpotential of 242 mV@10 mA cm−2 and remarkable stability over 350 h, but also achieves a low overpotential of 395 mV at a high current density of 800 mA cm−2, outperforming the pristine other control samples. Theoretical analysis reveals that the Mo2N‐stabilized NiSe/Ni2P heterostructure on NF enhances conductivity and optimizes adsorption energies of OER intermediates, leading to improved catalytic performance and stability. This work provides a new strategy for designing high‐performance, non‐precious metal OER catalysts for industrial applications and advancing sustainable hydrogen production.

Zhang, Zhi‐Jie; Xu, Hui‐Min; Song, Chen‐Yu; Shuai, Ting‐Yu; Zhan, Qi‐Ni; Zhu, Hong‐Rui; Fominski, Vyacheslav Yu.; Li, Gao‐Ren

doi: 10.1002/smll.202500689pmid: 40177913

The development of oxygen reduction reaction (ORR) catalysts with high catalytic activity, high stability, and low cost is of great significance for the development of rechargeable zinc–air batteries (ZABs). Designing heterostructures within the catalyst can regulate the charge distribution to enhance the electron transfer rate during the catalytic process, and optimize the adsorption of oxygen‐containing intermediates, resulting in high‐performance ORR catalysts. In this study, Fe2P/ZnS heterostructures supported on N‐doped porous carbon (Fe2P/ZnS@NC) are designed and fabricated through one‐step synthesis via high‐temperature pyrolysis. N‐doped carbon can significantly enhance the conductivity of carbon. The Fe2P/ZnS heterostructures optimize the electronic structure of the catalyst, thereby optimizing the adsorption of key intermediate *O at the Fe site and enhancing the ORR catalytic performance of Fe2P/ZnS@NC, with a half‐wave potential of 0.885 V. The Fe2P/ZnS@NC‐based ZABs show a maximum power density of 148.5 mW cm−2, an energy density of 818.2 mA h g−1, and excellent cycling stability (≈800 h), surpassing 40 wt.% Pt/C‐based ZABs. The above results show that the Fe2P/ZnS heterostructures play a key role in improving ORR catalytic performance for ZABs.