Capacitive deionization (CDI) works by using the electrical double layer on various materials including nanoporous carbons to separate ions from saline water. To help realize industrial application, there has been an increasing interest in the exploration of carbon materials from low cost, eco-friendly and abundant biomass for CDI to align with the demands of sustainable development strategies. Herein we report pyrolysis of xylose with KHCO₃ to prepare hierarchically porous carbon nanoflakes which display a satisfactory salt adsorption capacity of 16.29 mg g⁻¹. This novel strategy can design highly efficient carbon materials from naturally-developed biomass materials with its low preparation cost, environmentally friendliness and superior desalination performance. Our xylose-derived hierarchically porous carbon nanoflakes are promising for potential industrial application for CDI.

电容去离子（CDI）的工作原理是在包括纳米孔碳在内的各种材料上使用双电层，以将离子与盐水分离。为了帮助实现工业应用，越来越多的兴趣探索碳材料的低成本，生态友好和丰富的生物质用于CDI，以适应可持续发展战略的要求。在此，我们报道木糖与KHCO _3的热解作用，从而制备出分层多孔的碳纳米薄片，该薄片表现出令人满意的16.29 mg g ^-1的盐吸附能力。。这种新颖的策略可以以较低的制备成本，环境友好性和出色的脱盐性能，从天然开发的生物质材料中设计出高效的碳材料。我们的木糖衍生的多孔碳纳米薄片有望用于CDI的潜在工业应用。