Synthesis of new hollow nano-composite photocatalysts based yeast biomass has been considered as a future innovation technology to control air pollution. This work demonstrates that a green, environmentally friendly, sustainable, and facile hydrothermal carbonization route of low-cost and renewable yeast biomass used to fabricate natural doping N-colloidal carbon spheres (NCSs) as a hard template for hollow N-TiO₂/MnO₂. The presence of natural doping nitrogen serves as a stabilizer and reductant. Hence, the yeast provided a solid frame with deposits nitrogen to form the hybrid N/yeast precursor. The resulting NCSs were obtained by hydrothermal method at 180 °C for 6 h. The characterization was performed using SEM, TEM, XRD, FTIR and N₂ adsorption/desorption analysis. It was found that the findings fully retained the morphology of the yeast cells and the size of the hollow spheres was about 1.5–2 μm. The results of catalytic test showed that the new hollow nanosphere N-TiO₂/MnO₂ possessed a higher photodegradation activity for gaseous formaldehyde under visible irradiation than the commercial TiO₂, due to their higher surface area (160 m² g⁻¹), hollow structure and superior reducibility. Its catalytic efficiency was attained to be more than 90%, which is about 10 times higher than that of the conventional catalyst TiO₂–P25.

基于中空纳米复合光催化剂的新型酵母生物质的合成已被视为控制空气污染的未来创新技术。这项工作证明了低成本，可再生酵母生物质的绿色，环保，可持续和便捷的热液碳化路线，可用于制造天然掺杂的N-胶体碳球（NCS）作为中空N-TiO ₂ / MnO的硬模板₂。天然掺杂氮的存在充当稳定剂和还原剂。因此，酵母提供了具有沉积氮的固体框架，以形成杂化的N /酵母前体。通过水热法在180  °C下加热6  h得到NCS 。使用SEM，TEM，XRD，FTIR和N _2进行表征吸附/解吸分析。结果发现，这些发现完全保留了酵母细胞的形态，空心球的大小约为1.5–2μm  。催化试验结果表明，新型中空纳米球N-TiO ₂ / MnO ₂由于具有较高的表面积（160 m ² g ^-1），因此在可见光下对气态甲醛的光降解活性比市售TiO ₂高。中空结构和出色的还原性。它的催化效率达到了90％以上，是传统催化剂TiO ₂ -P25的约10倍。