To understand the electrical and charge transport phenomena in either single or large‐scale molecular junctions, direct current (DC) measurements are mainly utilized. The current–voltage data obtained from DC measurements on molecular junctions (MJs) are employed to infer charge transport parameters, including barrier height, contact resistance, attenuation factor (β), and underlying transport mechanisms. However, DC measurements can not separate the individual electrical components, as it produces a total current that flows in the molecular junctions. Contact resistance obtained from the DC measurements by extrapolating plot of resistance versus chain length can not make exact value. In addition, defected SAMs‐based MJs or junctions having a protective layer, DC measurements alone can predict neither proper electrical values nor the correct transport mechanisms and it lacks frequency response. Electrical impedance spectroscopy (EIS) along with the circuit model enables the identification of individual electrical components of the molecular junctions and faultless contact resistance values that facilitate the model of actual transport mechanisms. In this Review, the working principle of electrical impedance spectroscopy and circuit modeling to digitize the experimental results on various molecular junctions, is discussed. Overall, the EIS technique can serve as an excellent analytical tool for the proper electrical characterization that is highly desirable for molecular electronics.

We have shed light on the recent advances in imprinting chirality into achiral inorganic nanomaterials using organic chiral molecules, their structural analysis, growth mechanism, optical, optoelectronic, and bio-applications.

The present era has seen tremendous demands for low-cost electrochromic materials for visible-region multicolor display technology, paper-based, flexible, and wearable electronic devices, smart windows, and optoelectronic applications. Towards this goal, the authors report large-scale, high-yield and robust polyelectrochromic devices fabricated on rigid to flexible ITO substrates comprising novel anthracene containing viologen, (1,1″-bis(anthracen-9-ylmethyl)-[4,4″-bipyridine]-1,1'-diium bromide, abbreviated as AnV 2+ ), and polythiophene (P3HT). Interestingly, the devices show three states of reversible visible color in response to the applied bias, sub-second to second switching time (0.7 s/1.6 s), high coloration efficiency (484 cm 2 /C), and longer cycling stability up to 9,000 s (3,000 switching cycles). Introduction of the anthracene moieties to viologen inhibits the formation of an undesired dimer of cation radicals in response to the applied bias, otherwise the device's color-switching would be hampered when the bias polarity is reversed. The fabricated electrochromic devices are tested with commercially available low-cost cells to perform-a unique approach toward practical applications. The computational study facilitates the understanding of experimental results. Alternating current (AC)-based electrical impedance spectroscopy reveals that P3HT facilitates enhanced charge transfer to AnV 2+ . This work shows CMOS compatibility and can pave the way for developing cost-effective flexible and wearable electrochromic devices.

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