In this study, biochars (BCs) derived from corn stalk treated at various pyrolysis temperatures (350–950 °C) were prepared and then loaded with Cu²⁺ to form highly efficient algaecide, i.e. Cu²⁺-doped BC composites (Cu-BCs). The results showed BCs pyrolyzed at higher temperatures suppressed the growth of Microcystis aeruginosa in the order of BC550 ≫ BC750 > BC950, while BC350 accelerated cell growth due to the release of inorganic nutrients. The difference could be attributed to the physicochemical characteristics, including specific surface area, adsorption capacity of nutrients and the presence of particularly persistent free radicals. Furthermore, Cu-BCs exhibited the improved inactivation performance, but the 72 h growth inhibition rates and reaction activities of Cu-BCs were still influenced by the Cu²⁺ loading ratio and pyrolysis temperature. These results, reported for the first time, demonstrated the algae inactivation efficiency of pristine BCs, and Cu-BCs were principally manipulated by the biochar pyrolysis temperature.

在本研究中，以不同热解温度（350-950 °C）处理的玉米秸秆为原料制备生物炭（BC），然后负载Cu ²⁺形成高效除藻剂，即Cu ²⁺掺杂的BC复合材料（Cu- BC）。结果表明，较高温度下热解的BC对铜绿微囊藻的生长有抑制作用，其顺序为BC550≫BC750>BC950，而BC350则因释放无机营养物质而加速细胞生长。这种差异可能归因于物理化学特性，包括比表面积、营养物质的吸附能力以及特别持久的自由基的存在。此外，Cu-BCs表现出改善的灭活性能，但Cu-BCs的72 h生长抑制率和反应活性仍然受到Cu ²⁺负载率和热解温度的影响。这些结果是首次报道，证明了原始BC的藻类灭活效率，而Cu-BC主要受生物炭热解温度控制。