arXiv subjects

Ranjeev Kumar Parashar

Publications and source records attributed to Ranjeev Kumar Parashar.

3 recordsLinked to original sources

arXiv2024

Metal-organic Frameworks in Semiconductor Devices: A Revised Version

Metal-organic frameworks (MOFs) are a specific class of hybrid, crystalline, nano-porous materials made of metal-ion-based nodes and organic linkers. Most of the studies on MOFs largely focused on porosity, chemical and structural diversity, gas sorption, sensing, drug delivery, catalysis, and separation applications. In contrast, much less reports paid attention to understanding and tuning the electrical properties of MOFs. Poor electrical conductivity of MOFs reported in earlier studies, impeded their applications in electronics, optoelectronics, and renewable energy storage. To overcome this drawback, the MOF community has adopted several intriguing strategies for electronic applications. The present review focuses on creatively designed bulk MOFs and surface-anchored MOFs (SURMOFs) with different metal nodes (from transition metals to lanthanides), ligand functionalities, and doping entities, allowing tuning and enhancement of electrical conductivity. Diverse platforms for MOFs-based electronic device fabrications, conductivity measurements, and underlying charge transport mechanisms are also addressed. Overall, the review highlights the pros and cons of MOFs-based electronics, followed by an analysis of the future directions of research, including optimization of the MOF compositions, heterostructures, electrical contacts, device stacking, and further relevant options which can be of interest for MOF researchers and result in improved devices performance.

cond-mat.mtrl-sci↗

arXiv2023

Molecular lighting goes less powering

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, we report large-scale 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 AnV2+), and polythiophene (P3HT). Inter-estingly, 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), and high coloration efficiency (484 cm2/C), longer cycling stability up to 3000 s (103 switching cycles). Thanks to the anthracenes moieties introduced to viologen that inhibit formation of undesired dimer of cation radicals formed in response to the applied bias, other-wise it would hamper the devices reconfiguration. The devices are fully characterized, and electrochromic performances are ensured by bias-dependent UV-Vis, and Raman spectroscopy. The fabricated electro-chromic devices are tested with the commercially available low-cost cells to perform, which is highly de-sired for practical applications. The computational study facilitates the understanding of experimental re-sults. The alternating current (AC)-based electrical impedance spectroscopy reveals that P3HT facilitates reducing charge transfer resistance of the devices. Our work shows CMOS compatibility and one of the best-performing devices that could pave the way for developing cost-effective flexible, and wearable electrochromic devices.

cond-mat.mtrl-sci↗

arXiv2022

Metal-Organic Frameworks in Semiconductor Devices: Recent Advancements and a Bright Future

Metal-organic frameworks (MOFs) symbolize the particular class of hybrid crystalline, nano-porous materials made of either discrete metal ions or clusters with organic linkers. Past studies on MOFs-based materials largely focused on porosity, chemical and structural diversity, gas sorption, sensing, drug delivery, catalysis, and separation applications. However, initial efforts either neglected or have not gained much attention to refine the electrical conductivity of MOFs materials. MOFs reported earlier with poor electrical conductivity impeded to employ in electronics, optoelectronics, and renewable energy storage applications. To overcome this issue, the MOFs community has been engaged in improving electrical conductivity by adopting several intriguing strategies. We shed light on the charge transport mechanisms which are mainly two processes, either through a bond or through space. This review aims to showcase the current scenario on creatively designed MOF materials followed by fabrication advancement of high-quality molecular thin films, and semiconductor device fabrication for stimuli-responsive current-voltage (I-V) studies. Overall, the review addresses the pros and cons of the MOFs-based electronics, followed by our prediction on improvement MOFs composition, mechanically stable interfaces, device stacking, further relevant experiments which can be of great interest to the MOFs researchers in improving further devices performances.

cond-mat.mtrl-sci↗