@article{gutierrez2023combined,

title = {A combined experimental and DFT study on the zero valent iron/reduced graphene oxide doped QCM sensor for determination of trace concentrations of As using a Flow-batch system},

author = {Julián Gutiérrez and Yael N Robein and Julián Juan and Mar'ia S Di Nezio and Carolina Pistonesi and Estela A González and Rodrigo Santos and Marcelo F Pistonesi},

url = {https://www.sciencedirect.com/science/article/abs/pii/S0925400523019512},

doi = {https://doi.org/10.1016/j.snb.2023.135233},

year  = {2023},

date = {2023-12-30},

urldate = {2023-12-30},

journal = {Sensors and Actuators B: Chemical},

pages = {135233},

publisher = {Elsevier},

abstract = {A sensor based on a gold Quartz Crystal Microbalance (QCM) modified with nanoscale zero-valent iron nanoparticles (nZVI) anchored to reduced graphene oxide (rGO) was developed. An automated measurement microsystem was employed using QCM (modified and unmodified) as an arsine detector device. The QCM measurements of frequency changes are associated with total As concentration (III/V) in the samples. The gold surface QCM modification with nZVI/rGO improved the sensitivity in total As determination. The limit of detection (LOD) was 0.0062 

 for QCM-Au/nZVI/rGO, 100 times higher than the unmodified QCM-Au sensor. Moreover, studies of adsorption energy and electron density of As with QCM-Au/nZVI/rGO and QCM-Au systems were performed. For this purpose, Density Functional Theory (DFT) methodology was used employing arsine adsorption on magnetite nanoparticles supported on graphene, and also on Au as models. This theoretical-experimental research allows us to acquire knowledge of the interaction of Au/nZVI/rGO with As and confirms the experimental results.},

keywords = {Arsenic, Functional Theory (DFT) Calculations, LOD, nZVI/rGO, openQCM, QCM},

pubstate = {published},

tppubtype = {article}

}

@article{wang2023determination,

title = {Determination of electric and thermoelectric properties of molecular junctions by AFM in peak force tapping mode},

author = {Xinati Wang and Angelo Lamantia and Michael Jay and Hatef Sadeghi and Colin J Lambert and Oleg V Kolosov and Benjamin Robinson},

url = {https://iopscience.iop.org/article/10.1088/1361-6528/acdf67/meta},

doi = {https://doi.org/10.1088/1361-6528/acdf67},

year  = {2023},

date = {2023-06-19},

urldate = {2023-06-19},

journal = {Nanotechnology},

abstract = {Molecular thin films, such as self-assembled monolayers (SAMs), offer the possibility of translating the optimised thermophysical and electrical properties of high-Seebeck-coefficient single molecules to scalable device architectures. However, for many scanning probe-based approaches attempting to characterise such SAMs, there remains a significant challenge in recovering single-molecule equivalent values from large-area films due to the intrinsic uncertainty of the probe-sample contact area coupled with film damage caused by contact forces. Here we report a new reproducible non-destructive method for probing the electrical and thermoelectric properties of small assemblies (10 – 103) of thiol-terminated molecules arranged within a SAM on a gold surface, and demonstrate the successful and reproducible measurements of the equivalent single-molecule electrical conductivity and Seebeck values. We have used a modified thermal-electric force microscopy (TEFM) approach, which integrates the conductive-probe atomic force microscope, a sample positioned on a temperature-controlled heater, and a probe-sample peak-force feedback that interactively limits the normal force across the molecular junctions. The experimental results are interpreted by density functional theory calculations allowing quantification the electrical quantum transport properties of both single molecules and small clusters of molecules. Significantly, this approach effectively eliminates lateral forces between probe and sample, minimising disruption to the SAM while enabling simultaneous mapping of the SAMs nanomechanical properties, as well as electrical and/or thermoelectric response, thereby allowing correlation of the film properties.},

keywords = {Functional Theory (DFT) Calculations, Molecular Thin Films, openQCM, openQCM Q-1, QCM, QCM-D, Self-Assembled Monolayers (SAMs)},

pubstate = {published},

tppubtype = {article}

}