Soil contamination by heavy metals constitutes an important environmental problem, whereas field applicability of existing remediation technologies has encountered numerous obstacles, such as long operation time, high chemical cost, large energy consumption, secondary pollution, and soil degradation. Here we report the design and demonstration of a remediation method based on a concept of asymmetrical alternating current electrochemistry that achieves high degrees of contaminant removal for different heavy metals (copper, lead, cadmium) at different initial concentrations (from 100 to 10,000 ppm), all reaching corresponding regulation levels for residential scenario after rational treatment time (from 30 min to 6 h). No excessive nutrient loss in treated soil is observed and no secondary toxic product is produced. Long-term experiment and plant assay show the high sustainability of the method and its feasibility for agricultural use.

重金属污染土壤是一个重要的环境问题，而现有修复技术的现场适用性却遇到了许多障碍，例如运行时间长，化学药品成本高，能源消耗大，二次污染和土壤退化。在这里，我们报告了基于不对称交流电化学概念的修复方法的设计和演示，该方法可在不同的初始浓度（100至10,000 ppm）下，对不同重金属（铜，铅，镉）实现高度的污染物去除，经过合理的治疗时间（从30分钟到6小时），所有这些都达到了针对居住场景的相应法规水平。在处理过的土壤中没有观察到过多的养分流失，也没有产生次生毒性产物。