Advances in CO₂ Electroreduction over Hollow Fiber Gas Diffusion Electrodes

CO 2 electroreduction (CO 2 RR) to high‐value chemicals by renewable energy is a promising route for achieving carbon cycling. Traditional two‐dimensional planar electrodes applied in CO 2 RR are faced with problems of high mass transfer resistance, carbonate precipitation, flooding, and complicated structures, seriously limiting their CO 2 RR efficiency and application. Three‐dimensional hollow fiber gas diffusion electrodes (HFGDEs) are promising candidates due to their rich specific surface area, low mass transfer resistance, simplified component, and no flooding trouble, which are beneficial for achieving high current density as well as high CO 2 RR efficiency. In this review, we provide inspirations and positive paradigms for the rational design of HFGDE toward CO 2 RR by following part: 1. The mechanism of CO 2 RR. 2. The classification of the typical metal‐based CO 2 RR catalysts. 3. The preparation process of HFGDEs. 4. Recent advanced HFGDE studies for CO 2 RR. 5. Challenges at this stage and future development of HFGDEs towards accelerating application of industrial CO 2 reduction electrolyzers.