Carbon materials for high-performance potassium-ion energy-storage devices

Potassium-ion energy-storage devices have emerged as important candidates of next-generation energy-storage devices. Carbon materials have established themselves as vital roles in electrode of potassium-ion device due to environmentally friendly nature, low-cost, and large-current charge/discharge capability, ultra-long life and wide operation temperature region. In this timely review, a brief introduction of the state-of-the-art developments about carbon materials was provided. Subsequently, synthetic routes to carbon materials and their electrochemical performances in energy-storage devices were stated in detail. The relationships between rationally designed structures and electrochemical performances of carbon electrode materials were summarized to try to provide basic guidelines for material design. Potential research directions and important scientific problems of carbon materials were also proposed in the hope of solving the emerging problems of carbon-based energy-storage devices.