Publications by authors named "Brijesh Tripathi"

Dye-sensitized solar cells (DSSCs) have emerged as a potential candidate for third-generation thin film solar energy conversion systems because of their outstanding optoelectronic properties, cost-effectiveness, environmental friendliness, and easy manufacturing process. The electron transport layer is one of the most essential components in DSSCs since it plays a crucial role in the device's greatest performance. Silver ions as a dopant have drawn attention in DSSC device applications because of their stability under ambient conditions, decreased charge recombination, increased efficient charge transfer, and optical, structural, and electrochemical properties.

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In organic semiconductors, optical absorption is pivotal for the performance of optoelectronic devices. The absorption by the semiconductors generates excitons which dissociate into free charge carriers, resulting in energy conversion. Although high performance has been achieved in non-fullerene organic solar cells, their charge generation behavior is far from being well understood.

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Potential induced degradation of the shunt type (PID-s) in multi-crystalline silicon (mc-Si) solar cells is becoming critical for performance reduction of solar panels in large scale photovoltaic (PV) power plants. In this article PID-s has been investigated by applying high voltage stress on mc-Si solar cells for their degradation and recovery and results have been explained on the basis of DC and AC characterization. The efficiency decreases drastically from 15.

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A key challenge for researchers in the field of organic solar cells (OSCs) is to develop a physical model for a device that correctly describes the charge carrier transport phenomenon. In this article, an analytical study on the charge carrier transport phenomenon in an OSC is reported, which expresses a balance between free charge carrier generation and recombination in low mobility PTB7:PC71BM blend layers. First, the current density-voltage (J-V) data for the fabricated OSC were extracted from experiments by varying the incident power light intensity (IPL) and then analysis through theoretical simulation was used to quantify the dominant interface recombination parameters limiting the device's performance.

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Hematite (α-Fe2O3) nanostructures have been extensively studied as photo-anodes for the conversion of sunlight into chemical fuels by water splitting. A number of factors limit the photo-activity of pristine hematite nanostructures, including poor electrical conductivity and long penetration depth of light. Previous studies have shown that use of tin (Sn) as an n-type dopant can substantially enhance the photoactivity of hematite photoanodes by modifying their morphological, optical and electrical properties.

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The design and fabrication of better excitonic solar cells are the need of the hour for futuristic energy solutions. This designing needs a better understanding of the charge transport properties of excitonic solar cells. One of the popular methods of understanding the charge transport properties is the analysis of the J-V characteristics of a device through theoretical simulation at varied illumination intensity.

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Background: The hypomotility of colon observed in Hirschsprung’s disease (HD) has been attributed to congenital aganglionosis only. So far, it is not clear whether the contractility of colonic smooth muscle in this condition is altered or not. Therefore, the present study attempted to understand the contractile status of colonic segments of HD patients by examining carbachol and endothelin (ET-1) evoked colonic smooth muscle contractions in vitro .

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The present work reports a detailed electro-analytical framework for studying commercially available mono-crystalline silicon solar cells under varying illumination conditions to explore their application in the up-and-coming field of low concentration photovoltaics (LCPVs). The effect of low concentration illumination (>1-12 suns) on performance indicating parameters, i.e.

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Photoelectric conversion efficiency of a dye-sensitized solar cell was improved by trapping more light into the absorbing region using Ag nanoparticle. Improved light transmission is observed experimentally in silver nanoparticle coated FTO glass. The size of Ag nanoparticle is estimated as 110 nm by comparing theoretical results with experimental data.

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