Publications by authors named "Dibyashree Koushik"

Phosphorus oxide (PO ) capped by aluminum oxide (AlO) has recently been discovered to provide excellent surface passivation of crystalline silicon (c-Si). In this work, insights into the passivation mechanism of PO /AlO stacks are gained through a systematic study of the influence of deposition temperature ( = 100-300 °C) and annealing temperature ( = 200-500 °C) on the material and interface properties. It is found that employing lower deposition temperatures enables an improved passivation quality after annealing.

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Monolithic [Cs(MA FA )]Pb(IBr)/Cu(In,Ga)Se (perovskite/CIGS) tandem solar cells promise high performance and can be processed on flexible substrates, enabling cost-efficient and ultra-lightweight space photovoltaics with power-to-weight and power-to-cost ratios surpassing those of state-of-the-art III-V semiconductor-based multijunctions. However, to become a viable space technology, the full tandem stack must withstand the harsh radiation environments in space. Here, we design tailored and measurements to show that perovskite/CIGS cells retain over 85% of their initial efficiency even after 68 MeV proton irradiation at a dose of 2 × 10 p/cm.

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Ultrathin metal oxides prepared by atomic layer deposition (ALD) have gained utmost attention as moisture and thermal stress barrier layers in perovskite solar cells (PSCs). We have recently shown that 10 cycles of ALD AlO deposited directly on top of the CHNHPbICl perovskite material, are effective in delivering a superior PSC performance with 18% efficiency (compared to 15% of the AlO-free cell) with a long-term humidity-stability of more than 60 days. Motivated by these results, the present contribution focuses on the chemical modification which the CHNHPbICl perovskite undergoes upon growth of ALD AlO.

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In this work, we present an extensive characterization of plasma-assisted atomic-layer-deposited SnO layers, with the aim of identifying key material properties of SnO to serve as an efficient electron transport layer in perovskite solar cells (PSCs). Electrically resistive SnO films are fabricated at 50 °C, while a SnO film with a low electrical resistivity of 1.8 × 10 Ω cm, a carrier density of 9.

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This paper reports dehalogenation of various organohalides, especially aliphatic halocarbons and pesticides at reduced graphene oxide-silver nanocomposite (RGO@Ag). Several pesticides as well as chlorinated and fluorinated alkyl halides were chosen for this purpose. The composite and the products of degradation were characterized thoroughly by means of various microscopic and spectroscopic techniques.

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