Biocarbon with different microstructures derived from corn husks and their potassium storage properties

In this paper, biocarbon was prepared from corn husks as anode materials for potassium ion batteries at temperatures ranging from 700 to 1600 degrees C. The prepared biocarbon materials have amorphous phase structure and possess larger interlayer spacing than graphite. The biocarbon exhibits enhanced graphitic degree and decreased amounts of surface defects, while the carbonization temperature gradually increases. The obtained potassium ion battery electrode at 1300 degrees C acquired high reversible capacity up to 216.6 mAh.g(-1) at 0.1 A.g(-1) after 100 cycles, and retained 128.6 mAh.g(-1) at 1 A.g(-1) even after 500 cycles. The results indicate that the samples prepared at 1300 degrees C have better electrochemical performance than other samples prepared at different temperatures, which was attributed to the decisive influence of microstructure on surface-induced and intercalating potassium storage.

Automated summary

Biocarbon prepared from corn husks was used as anode material for potassium ion batteries, with the sample prepared at 1300 degrees Celsius showing the best electrochemical performance. The biocarbon exhibited higher graphitic degree and lower surface defects, leading to stable reversible capacity during cycling tests.