Spherical mesoporous tin dioxides are emerging sensing materials for fabrication of gas sensor applied in various fields. However, the synthesis of spherical mesoporous SnO₂ with uniform shape and small diameter (i.e., <100 nm) is still challenging. Herein, spherical mesoporous SnO₂ materials with tunable diameter (55−110 nm), large pore size (∼5.8 nm) and high specific surface area (80.9-185.6 m²/g) are synthesized via a self-template strategy by direct thermal decomposition of tin-polyphenol-formaldehyde polymers (TPFPs). Spherical TPFPs are synthesized via a sol-gel process using a low-cost, nontoxic and renewable natural polyphenol (i.e., tannic acid) as a ligand, formaldehyde as a cross-linking agent, tin ions as a metal source in alkaline conditions. Block copolymers can regulate the polymerization process and promote the formation of uniform spheres. The diameter of TPFPs and their derived spherical mesoporous SnO₂ can be adjusted by changing the amount of block copolymers. The gas sensors fabricated from spherical mesoporous SnO₂ exhibit excellent sensitivity to ethanol (18.9@50 ppm), fast response and recovery time (4 s / 44 s), good repeatability and long-term stability. This work demonstrates a reliable method for synthesis of spherical mesoporous SnO₂, which could be potentially applied in catalysis, sensing and energy storage.

球形中孔二氧化锡是新兴的传感材料，用于制造应用于各个领域的气体传感器。然而，具有均匀形状和小直径（即，＜100nm）的球形中孔SnO ₂的合成仍然具有挑战性。在此，采用自模板策略通过直接热合成具有可调直径（55-110 nm），大孔径（〜5.8 nm）和高比表面积（80.9-185.6 m ² / g）的球形介孔SnO ₂材料。锡多酚甲醛聚合物（TPFP）的分解。球形TPFP通过溶胶-凝胶工艺使用低成本，无毒且可再生的天然多酚（即（单宁酸）为配体，甲醛为交联剂，锡离子为碱性条件下的金属源。嵌段共聚物可以调节聚合过程并促进均匀球的形成。TPFP及其衍生的球形中孔SnO ₂的直径可以通过改变嵌段共聚物的量来调节。由球形中孔SnO ₂制成的气体传感器表现出对乙醇的出色灵敏度（18.9@50 ppm），快速响应和恢复时间（4 s / 44 s），良好的重复性和长期稳定性。这项工作证明了一种可靠的合成球形中孔SnO _2的方法，可以潜在地应用于催化，传感和能量存储。