Publications by authors named "D J Stacchiola"

The van der Waals (vdW) assemblies are the most common structures of materials. However, direct mapping of intermolecular electron clouds of a vdW assembly has never been obtained, even though the intramolecular electron clouds were visualized by atomic-resolution techniques. In this report, we unprecedentedly mapped the intermolecular electron cloud of the assemblies of ethanol molecules via ethyl groups with high-resolution atomic force microscopy and scanning tunneling microscopy at 5 K, leading to the first visualization of vdW molecular chains, in which ethanol molecules assemble into twin vdW molecular chains in a reverse parallel configuration on the Ag(111) plane.

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In this perspective, we discuss the potential impact on studies under controlled environments of a novel multimodal spectroscopic technique, optical photothermal infrared + Raman spectroscopy, which enables the simultaneous collection of infrared and Raman scattering spectra, along with hyperspectral imaging and chemical imaging with wavelength-independent sub-500 nm spatial resolution. A brief review of the current literature regarding the O-PTIR technique is presented along with recent work from our own lab on determining the crystallinity of soft and inorganic materials. The results highlight the possibility of resolving differences in the crystallinity of soft materials associated with changes in material processing.

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The sp-hybridized carbon chain (carbyne) is a representative 1D atomic material, whose bonding structure and chemical reactivity have remained a mystery for a century. Here, we report the unexpected alternating bond orders of 1.4 and 2.

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High areal capacitance for a practical supercapacitor electrode requires both large mass loading and high utilization efficiency of electroactive materials, which presents a great challenge. Herein, we demonstrated the unprecedented synthesis of superstructured NiMoO@CoMoO core-shell nanofiber arrays (NFAs) on a Mo-transition-layer-modified nickel foam (NF) current collector as a new material, achieving the synergistic combination of highly conductive CoMoO and electrochemical active NiMoO. Moreover, this superstructured material exhibited a large gravimetric capacitance of 1,282.

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Palladium-silver-based alloy catalysts have a great potential for CO-free hydrogen production from formic acid for fuel cell applications. However, the structural factors affecting the selectivity of formic acid decomposition are still debated. Herein, the decomposition pathways of formic acid on Pd-Ag alloys with different atomic configurations have been investigated to identify the alloy structures yielding high H selectively.

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