Conversion Mechanism of Soluble Alkylamide Precursors for the Synthesis of Colloidal Nitride Nanomaterials.

There are few molecular precursors that chemically convert to nitride nanomaterials, which severely limits the development of this important class of materials. Alkylamides are soluble and stable nitride precursors that can be based on the same primary amines that are often used in colloidal nanomaterial synthesis, but their conversion involves the breaking of stable C-N bonds through a mechanism that remained unknown up to now. A critical aspect of this conversion mechanism is uncovered here, involving a prelimary step whereby alkylamides are oxidized to N-alkylimines to yield NH2- amide species that are postulated to be the actual reactive precursors in the formation of indium nitride nanomaterials. Interestingly, this step also involves the concomitant reduction of indium(III) to In(0) nanodroplets, which consequently catalyze the growth of InN nanomaterials. The elucidation of the origin of the surprising reactivity of otherwise stable molecular precursors opens the door to the development of new solution-phase approaches for the synthesis of nitride materials.

Art in Alzheimer's care: promoting well-being in people with late-stage Alzheimer's disease.

The purpose of this qualitative study was to explore the responses of people with late-stage Alzheimer's disease (AD) to a creative bonding intervention (CBI). The CBI consisted of simple art activities. Guided by Reed's self-transcendence theory, research questions were "Will persons with late-stage AD show evidence of self-transcendence during the CBI?" and "Will persons with late-stage AD show evidence of well-being during the CBI?" Twelve CBI sessions, documented by videotape and field notes, were conducted with four participants. Themes emerged within two clusters: trusting/thirsting/following and choosing/connecting/reminiscing. An overarching category of "cocooning" described participants' world during the CBI as they displayed evidence of self-transcendence and well-being. The CBI is a strategy that can be implemented by staff families, and volunteers. Nurses are positioned to provide transformation leadership for implementation of creative approaches during care of people with late-stage AD, but administrative and financial support are needed.

Direct Deposition of Crystalline Ta3N5 Thin Films on FTO for PEC Water Splitting.

Tantalum nitride is a promising photoanode material for solar water splitting, but further study and practical use are constrained by the harsh conditions of the synthesis from Ta metal. Here, we report the direct deposition of crystalline Ta3N5 on fluorine-doped tin oxide (FTO) substrate via a custom-built atomic layer deposition (ALD) system. A combination of TaCl5 (Ta precursor) and ammonia (N source) was sequentially pulsed into the ALD reactor with the substrate heated to 550 °C to deposit compact and thin films of Ta3N5 with controllable thicknesses on FTO substrates. Importantly, it is shown that the FTO is chemically and structurally stable under the reducing conditions of ammonia at 550 °C. These electrodes produced an exceptional photocurrent onset potential of ∼0.3 V versus reversible hydrogen electrode (RHE) with a maximum photocurrent of ∼2.4 mA cm-2 at 1.23 V versus RHE. Results of photoelectrochemical investigations as a function of film thickness and illumination direction reveal that the performance of Ta3N5 is controlled by a hole diffusion length of ∼50 nm. These results are crucial for the successful integration of Ta3N5 in efficient unassisted water-splitting applications.

As Precious as Platinum: Iron Nitride for Electrocatalytic Oxidation of Liquid Ammonia.

The electrolysis of ammonia (NH3), a potential carrier for hydrogen fuel, has only been studied in detail in systems employing expensive, noble metal anodes such as platinum, ruthenium, and iridium. For NH3 to serve as a practical hydrogen storage medium, the electrolysis process must be energy efficient, scalable, and inexpensive. Clearly, alternatives to precious metals would greatly reduce costs if the performance of less expensive, more abundant metals rivaled those of their expensive counterparts. In this regard, no metal is less expensive than iron. Iron exhibits complex anodic behavior in liquid ammonia (NH3(l)), with a high sensitivity to trace amounts of dissolved water, and a tendency to corrosively dissolve with appropriate applied bias. However, with sufficient applied overpotential in distilled NH3(l), an iron nitride film forms in situ that is resistant to dissolution. On this in situ-modified surface, dinitrogen evolution out-performs anodic dissolution with an efficiency of over 95%. Amazingly, the onset potential for dinitrogen evolution in NH3(l) on this in situ-modified iron surface is almost identical to what is measured on a platinum electrode.