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1. Synthesis of volatile, reactive coinage metal 5,5-bicyclic amidinates with enhanced thermal stability for chemical vapor deposition

   https://doi.org/10.1039/c9dt01202h  

   Tong, Liuchuan; Davis, Luke M.; Gong, Xian; Feng, Jun; Beh, Eugene S.; Gordon, Roy G. (January 2019, Dalton Transactions)

   Many microelectronic devices require thin films of silver or gold as wiring layers. We report silver( i ) and gold( i ) bicyclic amidinate complexes, wherein the constrained ligand geometry lessens the propensity for thermal decomposition. These new volatile compounds provide metallic films of silver and gold during CVD with hydrogen below 230 °C. 

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2. Macrocyclic and acyclic supramolecular elements for co-precipitation of square-planar gold( iii ) tetrahalide complexes

   https://doi.org/10.1039/D0QO01562H  

   Shaffer, Cassandra C.; Smith, Bradley D. (March 2021, Organic Chemistry Frontiers)

   null (Ed.)

   Macrocyclic hosts have long been used for guest encapsulation, and recently a new application has emerged; employment as supramolecular elements for capture and recovery of gold through host/guest co-precipitation. The guests are square-planar tetrahaloaurate anions, practically important gold complexes with a capacity to engage in non-covalent interactions such as hydrogen bonding and Au–π interactions. The successful macrocyclic hosts for co-precipitation include cyclodextrins, cucurbiturils, and cyclophanes, with recent expansion of the structural scope to include acyclic amides. 

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3. Heat Transfer in Gold Interfaces Capped with Thiolated Polyethylene Glycol: A Molecular Dynamics Study

   https://doi.org/10.1021/acs.jpcb.3c05238  

   Shavalier, Sydney A.; Gezelter, J. Daniel (November 2023, The Journal of Physical Chemistry B)

   Reverse nonequilibrium molecular dynamics simulations were used to study heat transport in solvated gold interfaces which have been functionalized with a low-molecular weight thiolated polyethylene glycol (PEG). The gold interfaces studied included (111), (110), and (100) facets as well as spherical nanoparticles with radii of 10 and 20 Å. The embedded atom model (EAM) and the polarizable density-readjusted embedded atom model (DR-EAM) were implemented to determine the effect of metal polarizability on heat transport properties. We find that the interfacial thermal conductance values for thiolated PEG-capped interfaces are higher than those for pristine gold interfaces. Hydrogen bonding between the thiolated PEG and solvent differs between planar facets and the nanospheres, suggesting one mechanism for enhanced transfer of energy, while the covalent gold sulfur bond appears to create the largest barrier to thermal conduction. Through analysis of vibrational power spectra, we find an enhanced population at low-frequency heat-carrying modes for the nanospheres, which may also explain the higher mean interfacial thermal conductance (G) value. 

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4. Gold Catalysts Synthesized Using a Modified Incipient Wetness Impregnation Method for Propylene Epoxidation

   https://doi.org/10.1002/cctc.202001053  

   Lu, Zheng; Kunisch, Jacob; Gan, Zhuoran; Bunian, Muntaseer; Wu, Tianpin; Lei, Yu (September 2020, ChemCatChem)

   Abstract Propylene epoxidation in the presence of oxygen and hydrogen were measured for a series of Au/TS‐1 catalysts prepared by a modified incipient wetness impregnation (mIWI) method. This method enables precise control of the Au : Ti ratio in the Au/TS‐1 catalysts. The optimized Au/TS‐1 catalyst exhibited 12 % propylene conversion, 87 % PO selectivity, and 25 % hydrogen efficiency. The particle size of gold nanoparticles prepared by the modified IWI was between 2 and 3 nm, as demonstrated by XRD patterns, STEM images, and X‐ray absorption spectroscopy at the Au L₃edge. XPS spectra showed that the surface species on the catalysts were similar. UV‐Vis spectra suggested that in the modified IWI method, the chlorine ligands in Au(Cl)₄⁻were replaced by hydroxyl groups, which contributes to form small gold nanoparticles. Kinetic studies showed that the active sites of Au(mIWI)/TS‐1 are similar to the Au(DP)/TS‐1 prepared by deposition precipitation. 

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5. Programmable Electrochemical Stimulation on a Large-Scale CMOS Microelectrode Array

   https://doi.org/10.1109/BioCAS54905.2022.9948674  

   Joshi, Pushkaraj S.; Hu, Kangping; Larkin, Joseph W.; Rosenstein, Jacob K. (October 2022, IEEE)

   In this paper we present spatio-temporally controlled electrochemical stimulation of aqueous samples using an integrated CMOS microelectrode array with 131,072 pixels. We demonstrate programmable gold electrodeposition in arbitrary spatial patterns, controllable electrolysis to produce microscale hydrogen bubbles, and spatially targeted electrochemical pH modulation. Dense spatially-addressable electrochemical stimulation is important for a wide range of bioelectronics applications. 

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