Biochar is an important bio-material used to mitigate environmental and agronomic problems. The complex outdoor environment, which includes exposure to solar radiation, greatly influences biochar structure, which in turn impacts its functions when it is used in outdoors. The objective of this study is to understand the dynamics associated with the physical and chemical changes that occur in bamboo biochar (BB) prepared at different final temperatures during exposure to damaging radiation. The basic physical and chemical properties of fresh and accelerated weathered BBs were investigated by measuring the chemical element, ash content, BET surface area, color changes. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, thermogravimetry analysis and differential scanning calorimetry were used to determine the changes in functional groups, the variation in the surface element species distribution and the differences in thermochemical property of BBs. The experimental results showed that clear changes in BBs were obtained after 400 h of accelerated weathering. The C and N contents of BBs declined, and its O content increased. The average changes in color and decrease in residue yield of BBs were 1.02 and 1.58%, respectively. The average growth rates of O/C ratio (determined by elemental analysis), C4, and O2 of BBs were 17.04%, 13.88% and 86.63%, respectively. These results illustrate that the BBs underwent a series of photooxidation reactions when exposed to UV radiation. The increase of surface oxygen-containing functional groups may improve the surface activities of BB with respect to soil-amelioration applications, pollutant-degradation efficiency and the adsorbability toward aqueous contaminants.

生物炭是用于减轻环境和农学问题的重要生物材料。复杂的户外环境（包括暴露于太阳辐射下）极大地影响了生物炭的结构，进而影响了其在户外使用时的功能。这项研究的目的是了解在暴露于有害辐射期间在不同最终温度下制备的竹生物炭（BB）中发生的物理和化学变化相关的动力学。通过测量化学元素，灰分，BET表面积，颜色变化，研究了新鲜的和加速风化的BB的基本物理和化学性质。傅里叶变换红外光谱，X射线光电子能谱，用热重分析和差示扫描量热法测定了功能基团的变化，表面元素种类分布的变化以及BBs的热化学性质的差异。实验结果表明，在加速风化400小时后，BB的变化明显。BBs的C和N含量下降，O含量增加。BB的平均颜色变化和残渣产率降低分别为1.02和1.58％。BB的O / C比（通过元素分析确定），C4和O2的平均增长率分别为17.04％，13.88％和86.63％。这些结果说明，BBs暴露于紫外线辐射后发生了一系列的光氧化反应。