In this study, in situ detection of the transient cavitation intensity during the sonochemical synthesis of Zinc-based Oxide (ZBO) is realized. At a fixed ethanol/water ratio of 25%, the transient cavitation intensity initially increases to a certain level during the nucleation stage of ZBO since the growth units of ZBO serve as supplementary induction sites for transient cavitation bubbles. Once the process surpasses the critical supersaturation point of ZBO growth units, a decrease of transient cavitation intensity is observed because the formation of massive ZBO nanocrystals may cause ultrasonic scattering attention. As a result, high-aspect-ratio ZBO nanorods are formed due to the preferential growth along the [001] direction. In addition, by increasing the ethanol/water ratio, a similar but decreasing trend in the time-dependent transient cavitation intensity during the ZBO synthesis process is obtained. This results in fewer ethanol molecules detaching from the ZBO (001) crystal surface, due to reduced cavitation bubble explosions, thereby inhibiting ZBO growth along the [001] direction. At an ethanol/water ratio of 75%, a morphological transition from slender nanorods to ultra-thin Zn(NO)(OH)·2HO nanoflakes is facilitated. These ultra-thin nanoflakes demonstrate promising photocatalytic performance. This work provides a rational sonochemical approach for synthesizing facet-controlled growth of nanocrystals.

中文翻译：

---

超声空化调制锌基氧化物纳米晶面生长

本研究实现了声化学合成锌基氧化物（ZBO）过程中瞬态空化强度的原位检测。在乙醇/水比例固定为 25% 时，ZBO 成核阶段的瞬时空化强度最初增加到一定水平，因为 ZBO 的生长单元充当瞬时空化气泡的补充诱导位点。一旦该过程超过ZBO生长单元的临界过饱和点，就会观察到瞬态空化强度的降低，因为大量ZBO纳米晶体的形成可能会引起超声散射的关注。结果，由于沿[001]方向优先生长，形成高纵横比的ZBO纳米棒。此外，通过增加乙醇/水的比例，在ZBO合成过程中获得了类似但随时间变化的瞬态空化强度下降的趋势。由于空化气泡爆炸减少，这导致从 ZBO (001) 晶体表面脱离的乙醇分子减少，从而抑制 ZBO 沿 [001] 方向生长。当乙醇/水比例为75%时，促进了从细长纳米棒到超薄Zn(NO)(OH)·2HO纳米片的形态转变。这些超薄纳米薄片表现出有前景的光催化性能。这项工作为合成纳米晶体的面控制生长提供了合理的声化学方法。