Highlights Fabrication, characterizations and photothermal properties of MXenes are systematically described. Photothermal-derived antibacterial performances and mechanisms of MXenes-based materials are summarized and reviewed. Recent advances in the derivative applications relying on antibacterial properties of MXenes-based materials, including in vitro and in vivo sterilization, solar water evaporation and purification, and flexible antibacterial fabrics, are investigated. Abstract The pernicious bacterial proliferation and emergence of super-resistant bacteria have already posed a great threat to public health, which drives researchers to develop antibiotic-free strategies to eradicate these fierce microbes. Although enormous achievements have already been achieved, it remains an arduous challenge to realize efficient sterilization to cut off the drug resistance generation. Recently, photothermal therapy (PTT) has emerged as a promising solution to efficiently damage the integrity of pathogenic bacteria based on hyperthermia beyond their tolerance. Until now, numerous photothermal agents have been studied for antimicrobial PTT. Among them, MXenes (a type of two-dimensional transition metal carbides or nitrides) are extensively investigated as one of the most promising candidates due to their high aspect ratio, atomic-thin thickness, excellent photothermal performance, low cytotoxicity, and ultrahigh dispersibility in aqueous systems. Besides, the enormous application scenarios using their antibacterial properties can be tailored via elaborated designs of MXenes-based materials. In this review, the synthetic approaches and textural properties of MXenes have been systematically presented first, and then the photothermal properties and sterilization mechanisms using MXenes-based materials are documented. Subsequently, recent progress in diverse fields making use of the photothermal and antibacterial performances of MXenes-based materials are well summarized to reveal the potential applications of these materials for various purposes, including in vitro and in vivo sterilization, solar water evaporation and purification, and flexible antibacterial fabrics. Last but not least, the current challenges and future perspectives are discussed to provide theoretical guidance for the fabrication of efficient antimicrobial systems using MXenes.

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Achieving scalable synthesis of nanoscale transition‐metal carbides (TMCs), regarded as substitutes for platinum‐group noble metals, remains an ongoing challenge. Herein, a 100‐g scale synthesis of single‐phased cobalt carbide (Co2C) through carburization of Co‐based Prussian Blue Analog (Co‐PBA) is reported in CO2/H2 atmosphere under mild conditions (230 °C, ambient pressure). Textural property investigations indicate a successful preparation of orthorhombic‐phased Co2C nanomaterials with Pt‐group–like electronic properties. As a demonstration, Co2C achieves landmark photo‐assisted thermal catalytic CO2 conversion rates with photo‐switched product selectivity, which far exceeds the representative Pt‐group‐metal–based catalysts. This impressive result is attributed to the excellent activation of reactants, colorific light absorption, and photo‐to‐thermal conversion capacities. In addition to CO2 hydrogenation, the versatile Co2C materials show huge prospects in antibacterial therapy, interfacial water evaporation, electrochemical hydrogen evolution reaction, and battery technologies. This study paves the way toward unlocking the potential of multi‐functional Co2C nanomaterials.

Solar-driven interfacial steam generation is considered as a sustainable and cost-effective approach to produce freshwater from seawater or sewage, whereas unavoidable microbial contamination and low evaporation efficiency remain challenges. Herein, we report a high-performance and antibacterial 3D Ag/MXene@chitosan hydrogel (described as AM/Ch gel) evaporator through incorporation of two-dimensional (2D) Ag/MXene composites into three-dimensional (3D) chitosan hydrogel. Thanks to the synergistic contributions from chitosan hydrogel matrix and Ag/MXene composites, 3D AM/Ch gel could completely eradicate both E. coli and S. aureus under simulated solar light irradiation, ensuring the production of microbial-free drinkable water. Benefiting from the superb photo-to-thermal conversion behavior and feasible water transportation in the 3D networks, the prepared AM/Ch gel-based evaporator exhibits intriguing solar steam generation performances, with evaporation rate and solar energy utilization efficiency of 3.22 kg m–2 h–1 and 94.9% under irradiation of 0.2 W cm–2, respectively. As a demonstration, the quality of collected liquid water evaporated from seawater adopted from the Yellow Sea, China, well satisfies the requirement for drinking water from World Health Organization. Moreover, the AM/Ch gel exhibits high flexibility and chemical stability, excellent dye molecules adsorption capacity and self-cleaning ability, indicating its promising potential for durable and sustainable water distillation.