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The advancement of economical and readily available electrocatalysts for the oxygen reduction reaction (ORR) holds paramount importance in the advancement of fuel cells and metal‐air batteries. Recently, 2D non‐metallic materials have obtained substantial attention as viable alternatives for ORR catalysts due to their manifold advantages, encompassing low cost, ample availability, substantial surface‐to‐volume ratio, high conductivity, exceptional durability, and competitive activity. The augmented ORR performances observed in metal‐free 2D materials typically arise from heteroatom doping, defects, or the formation of heterostructures. Here, the authors delve into the realm of electrocatalysts for the ORR, pivoting around metal‐free 2D materials. Initially, the merits of metal‐free 2D materials are explored and the reaction mechanism of the ORR is dissected. Subsequently, a comprehensive survey of diverse metal‐free 2D materials is presented, tracing their evolutionary journey from fundamental concepts to pragmatic applications in the context of ORR. Substantial importance is given on the exploration of various strategies for enhancing metal‐free 2D materials and assessing their impact on inherent material performance, including electronic properties. Finally, the challenges and future prospects that lie ahead for metal‐free 2D materials are underscored, as they aspire to serve as efficient ORR electrocatalysts. [ABSTRACT FROM AUTHOR]

The 1T phase of MoS2 exhibits much higher electrocatalytic activity and better stability than the 2H phase. However, the harsh conditions of 1T phase synthesis remain a significant challenge for various extensions and applications of MoS2. In this work, a simple hydrothermal‐based synthesis method for the phase transition of MoS2 is being developed. For this, the NH2‐MIL‐125(Ti) (Ti MOF) is successfully utilized to induce the phase transition of MoS2 from 2H to 1T, achieving a high conversion ratio of ≈78.3%. The optimum phase‐induced MoS2/Ti MOF heterostructure demonstrates enhanced oxygen evolution reaction (OER) performance, showing an overpotential of 290 mV at a current density of 10 mA cm−2. The density functional theory (DFT) calculations are demonstrating the benefits of this phase transition, determining the electronic properties and OER performance of MoS2. [ABSTRACT FROM AUTHOR]

The harsh operating conditions of the oxygen evolution reaction (OER) in water electrolysis severely degrade the activity and stability of the electrocatalysts due to elemental leaching or particle agglomeration. Therefore, it is crucial to incorporate support materials that effectively immobilize catalyst particles for developing efficient OER catalysts. This review aims to highlight the role of MXene as a support material to improve the performance of OER catalysts. First, the extended OER mechanism is briefly described in terms of the effect of MXene support on OER catalysts. Then, various synthesis methods of MXene and catalyst‐MXene compounds are introduced, and important properties of MXene that are beneficial to improve OER performances are discussed. The electrocatalytic results of the enhanced OER catalysts due to the effective MXene support are also summarized. Finally, future challenges and prospects are proposed for utilizing MXene as an excellent support material for various electrocatalysis. [ABSTRACT FROM AUTHOR]

Plastics, which are versatile and widely used materials, are being improperly disposed of in landfills or water bodies, leading to significant environmental damage. Traditional methods for plastic waste management, such as thermal decomposition and gasification, require high energy input. Recycling plastics back into their original form is a sustainable option, but demands high purity of recycled plastics and complex pre- and post-treatments. Electrochemical upcycling has recently emerged as a new alternative, which utilizes electrochemical reactions to transform plastic waste into valuable chemical compounds. Its advantages include the ability to operate under mild conditions, the use of eco-friendly energy sources, and increased energy efficiency. This review article provides an overview of electrochemical upcycling technologies for various types of waste plastics and explores their potential for generating value-added products. It also highlights the importance of understanding reaction mechanisms, electrochemical reaction systems, and catalyst development. We believe that the integration of electrochemical upcycling and chemical depolymerization has the potential to contribute to a circular economy and mitigate the environmental impact of plastic waste. [ABSTRACT FROM AUTHOR]