Koo Kunmo, Li Zhiwei, Liu Yukun, Ribet Stephanie M, Fu Xianbiao, Jia Ying, Chen Xinqi, Shekhawat Gajendra, Smeets Paul J M, Dos Reis Roberto, Park Jungjae, Yuk Jong Min, Hu Xiaobing, Dravid Vinayak P
Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208, USA.
The NUANCE Center, Northwestern University, Evanston, IL 60208, USA.
Sci Adv. 2024 Jan 19;10(3):eadj6417. doi: 10.1126/sciadv.adj6417. Epub 2024 Jan 17.
Utilization of in situ/operando methods with broad beams and localized probes has accelerated our understanding of fluid-surface interactions in recent decades. The closed-cell microchips based on silicon nitride (SiN) are widely used as "nanoscale reactors" inside the high-vacuum electron microscopes. However, the field has been stalled by the high background scattering from encapsulation (typically ~100 nanometers) that severely limits the figures of merit for in situ performance. This adverse effect is particularly notorious for gas cell as the sealing membranes dominate the overall scattering, thereby blurring any meaningful signals and limiting the resolution. Herein, we show that by adopting the back-supporting strategy, encapsulating membrane can be reduced substantially, down to ~10 nanometers while maintaining structural resiliency. The systematic gas cell work demonstrates advantages in figures of merit for hitherto the highest spatial resolution and spectral visibility. Furthermore, this strategy can be broadly adopted into other types of microchips, thus having broader impact beyond the in situ/operando fields.
近几十年来，使用宽束和局部探针的原位/操作方法加速了我们对流体-表面相互作用的理解。基于氮化硅（SiN）的闭孔微芯片被广泛用作高真空电子显微镜内的“纳米级反应器”。然而，该领域因封装产生的高背景散射（通常约为100纳米）而停滞不前，这严重限制了原位性能的品质因数。对于气室而言，这种不利影响尤为显著，因为密封膜主导了整体散射，从而模糊了任何有意义的信号并限制了分辨率。在此，我们表明，通过采用背支撑策略，可以在保持结构弹性的同时，将封装膜大幅减少至约10纳米。系统的气室工作证明了在品质因数方面的优势，实现了迄今为止最高的空间分辨率和光谱可见性。此外，该策略可广泛应用于其他类型的微芯片，从而在原位/操作领域之外产生更广泛的影响。
