Deep Eutectic Solvent with Prussian Blue and Tungsten Oxide for Green and Low-Cost Electrochromic Devices

Tungsten oxide clusters deposited on rutile TiO2 (110) single crystals were used as a model system for heterogenous oxide-oxide bifunctional catalysts. The population of different thermal reaction routes in methanol...

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Lifetime of electrochromic optical transition cycling of ethyl viologen diperchlorate-based electrochromic devices

SN Applied Sciences ◽

10.1007/s42452-021-04552-1 ◽

2021 ◽

Vol 3 (5) ◽

Author(s):

Logan G. Kiefer ◽

Christian J. Robert ◽

Taylor D. Sparks

Keyword(s):

Optical Transition ◽

Low Cost ◽

Cycling Performance ◽

Power Measurement ◽

Electrochromic Devices ◽

Metal Oxide Films ◽

Cycle Times ◽

Vis Spectroscopy ◽

Multiple Devices ◽

Measurement Devices

AbstractElectrochromic materials and devices are enabling a variety of advanced technologies. Gel-based organic electrochromic molecules such as ethyl viologen diperchlorate are attractive options due to their simple device design and low cost processing options relative to the more expensive and complex transition metal oxide films. However, electrochromic devices are subject to extensive cycling in which failure and fatigue can eventually occur. This work presents the lifetime cycling performance of ethyl viologen diperchlorate-based electrochromic devices using two different anodic compounds, hydroquinone and ferrocene, which are cycled at different voltages, 3 V and 1.2 V, respectively. Multiple devices are cycled until failure with periodic device characterization via UV–Vis spectroscopy, electrical resistance and power measurement, and transition duration measurement. Devices with hydroquinone can transition quickly. Cycle times are $$\sim$$ ∼ 30 s in these samples, however, these samples also typically fail before 3000 cycles. On the other hand, devices using ferrocene transition more slowly (total cycle time $$\sim$$ ∼ 2 min), but have superior cycling performance with all samples surviving beyond 10,000 cycles while complying with ASTM E2141-14 standard.

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Organotrialkoxysilane-Functionalized Prussian Blue Nanoparticles-Mediated Fluorescence Sensing of Arsenic(III)

Nanomaterials ◽

10.3390/nano11051145 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1145

Author(s):

Prem. C. Pandey ◽

Shubhangi Shukla ◽

Roger J. Narayan

Keyword(s):

Prussian Blue ◽

Chemical Reduction ◽

Low Cost ◽

Three Dimensional ◽

Heterogeneous Systems ◽

Lattice Points ◽

Radiative Energy ◽

Fluorescence Sensing ◽

Emission Signal ◽

Prussian Blue Nanoparticles

Prussian blue nanoparticles (PBN) exhibit selective fluorescence quenching behavior with heavy metal ions; in addition, they possess characteristic oxidant properties both for liquid–liquid and liquid–solid interface catalysis. Here, we propose to study the detection and efficient removal of toxic arsenic(III) species by materializing these dual functions of PBN. A sophisticated PBN-sensitized fluorometric switching system for dosage-dependent detection of As3+ along with PBN-integrated SiO2 platforms as a column adsorbent for biphasic oxidation and elimination of As3+ have been developed. Colloidal PBN were obtained by a facile two-step process involving chemical reduction in the presence of 2-(3,4-epoxycyclohexyl)ethyl trimethoxysilane (EETMSi) and cyclohexanone as reducing agents, while heterogeneous systems were formulated via EETMSi, which triggered in situ growth of PBN inside the three-dimensional framework of silica gel and silica nanoparticles (SiO2). PBN-induced quenching of the emission signal was recorded with an As3+ concentration (0.05–1.6 ppm)-dependent fluorometric titration system, owing to the potential excitation window of PBN (at 480–500 nm), which ultimately restricts the radiative energy transfer. The detection limit for this arrangement is estimated around 0.025 ppm. Furthermore, the mesoporous and macroporous PBN-integrated SiO2 arrangements might act as stationary phase in chromatographic studies to significantly remove As3+. Besides physisorption, significant electron exchange between Fe3+/Fe2+ lattice points and As3+ ions enable complete conversion to less toxic As5+ ions with the repeated influx of mobile phase. PBN-integrated SiO2 matrices were successfully restored after segregating the target ions. This study indicates that PBN and PBN-integrated SiO2 platforms may enable straightforward and low-cost removal of arsenic from contaminated water.

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