In situ chemoresistive sensing in the environmental TEM: probing functional devices and their nanoscale morphology

Abstract

In situ transmission electron microscopy provides exciting opportunities to address fundamental questions and technological aspects related to functional nanomaterials, including the structure-property relationships of miniaturized electronic devices. Herein, we report the in situ chemoresistive sensing in the environmental transmission electron microscope (TEM) with a single SnO nanowire device, studying the impact of surface functionalization with heterogeneous nanocatalysts. By detecting toxic carbon monoxide (CO) gas at ppm-level concentrations inside the microscope column, the sensing properties of a single SnO nanowire were characterized before and after decoration with hybrid Fe-Pd nanocubes. The structural changes of the supported nanoparticles induced by sensor operation were revealed, enabling direct correlation with CO sensing properties. Our novel approach is applicable for a broad range of functional nanomaterials and paves the way for future studies on the relationship between chemoresistive properties and nanoscale morphology.

Computational Modeling of Nanoparticle Coalescence

“…[125] Potential applications for nanoparticulated films include biomaterials, [87,126] structural and electronic ceramics, [127] catalysts, sensors, etc. [54,[128][129][130] Various parameters can characterize these films, such as: i) Morphology: for example, flat metallic scaffolds do not enable the adhesion and organization of living cells, but rough, biocompatible implant scaffolds need to be designed instead. [92,126] ii) Porosity: in high surface-area applications such as catalysis, porosity is of utmost importance since it determines both catalytic activity and selectivity.…”

“…However, this is no trivial task since nanoparticle deposition is a complicated, random process, which is very sensitive to subtle changes in various parameters such as cluster size or deposition energy . Potential applications for nanoparticulated films include biomaterials, structural and electronic ceramics, catalysts, sensors, etc …”

NanoMaterialsCAD: Flexible Software for the Design of Nanostructures

“…[26,27,48] Especially in the field of chemical (bio-) sensing, the nature of the NP-oxide support interface and the resulting interactions can determine the sensitivity and selectivity of the sensor device. [49][50][51] Ab initio theoretical studies based on reallife experimental data are often necessary to characterize these interfaces accurately. To this end, HRTEM is a valuable tool, providing detailed information with atomic resolution on real systems.…”

Atomic-scale structure and chemical sensing application of ultrasmall size-selected Pt nanoparticles supported on SnO2

“…Magnetron sputtering inert-gas condensation, a versatile technique for the growth of single-and multicomponent nanoparticles with controlled size and morphology, [21][22][23] was employed for the deposition of pre-formed, size-selected Pt nanoparticles. A wide range of nanoparticle functionalities has been achieved with this method, e.g., percolating nanoparticle films for chemoresistive sensing, [24][25][26][27][28][29][30] nanoparticle-decorated metal oxide nanowire devices for chemoresistive sensing, [31][32][33] supported nanoparticles for catalysis and electrochemistry, [34][35][36][37] magnetic nanoparticles, 30,[38][39][40] nanoparticles embedded in multi-layered anodes for lithium ion batteries 41 and nanoportals for hydrogen storage applications. 42 Here, we demonstrate a new approach for the surface functionalization of micro-machined chemical sensor devices realized in complementary metal-oxide-semiconductor (CMOS) technology, in particular by depositing ultrasmall Pt nanocatalysts by magnetron sputtering inert-gas condensation onto nanocrystalline SnO 2 thin films integrated on a suspended microhotplate platform.…”