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Electrochemical CO2 reduction reaction (CO2RR) coupled with renewable electricity holds promises for efficient mitigation of carbon emission impacts on the environment and turning CO2 into valuable chemicals. One important task in CO2RR development is the design and fabrication of efficient electrodes for stable operation in the long term. Gas‐diffusion electrodes (GDEs) have been employed to continuously feed CO2 to the electrolyzers. Despite significant advances in GDE design and tailoring GDE properties, the present GDEs often suffer from the critical issue of flooding due to the electrowetting of carbon‐based substrates, which hinders the transition to industrial application. To address flooding, GDEs with intrinsically hydrophobic polymeric substrates have been recently fabricated and have shown promising performances. Herein, the advances and challenges associated with carbon‐free GDEs are reviewed for CO2RR. This review first briefly outlines GDE and electrolyzers basics. Through critical discussion around the shortcomings of conventional carbon‐based GDEs, the most recent efforts to resolve flooding are summarized. Subsequently, the advances, advantages, and challenges of carbon‐free GDEs are elaborated. Finally, priorities for future studies are suggested, with the aim to support the advancement and scale‐up of carbon‐free GDEs and extend them to other electrochemical systems where gas and the electrolyte are in contact. [ABSTRACT FROM AUTHOR]

An ever-increasing market demand has stimulated the soaring enthusiasm of researchers to develop wide-temperature super-capacitors (SCs). The active electrode is one of the most important parts of SC, which is directly related to the energy density, power transmission and long-term cyclability of the device in the wide-temperature environment. Compared with the SC electrodes aimed for room-temperature application, the SC electrodes for operating at wide-temperature scene often face greater challenges. In this review, the main challenges of SC electrodes under various temperature conditions, including low, high and cross-fade temperatures, are summarized. The relevant performance decay and failure mechanisms of wide-temperature SC electrodes are analyzed. In addition, this review deals with the recent studies and developments in robust wide-temperature SC electrodes with respect to the rational design of electrode structures and the exploitation of advanced active materials. Finally, the future directions for exploring reliable wide-temperature SCs are also proposed. [ABSTRACT FROM AUTHOR]