Publications by authors named "Roja Singh"

Enhancing reproducibility, repeatability, as well as facilitating transferability between laboratories will accelerate the progress in many material domains, wherein perovskite-based optoelectronics are a prime use case. This study presents fully automated perovskite thin film processing using a commercial spin-coating robot in an inert atmosphere. We successfully apply this novel processing method to antisolvent quenching.

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The long-term stability of perovskite solar cells (PSCs) remains a bottleneck for commercialization. While studies on the stoichiometry and morphology of PSCs with regard to performance are prevalent, understanding the influence of these factors on their long-term stability is lacking. In this work, we evaluate the impact of stoichiometry and morphology on the long-term stability of cesium formamidinium-based PSCs.

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The recent tremendous progress in monolithic perovskite-based double-junction solar cells is just the start of a new era of ultra-high-efficiency multi-junction photovoltaics. We report on triple-junction perovskite-perovskite-silicon solar cells with a record power conversion efficiency of 24.4%.

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Optical interference filters (OIFs) are vital components for a wide range of optical and photonic systems. They are pivotal in controlling spectral transmission and reflection upon demand. OIFs rely on optical interference of the incident wave at multilayers, which are fabricated with nanometer precision.

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Monolithic two-terminal (2T) perovskite/CuInSe (CIS) tandem solar cells (TSCs) combine the promise of an efficient tandem photovoltaic (PV) technology with the simplicity of an all-thin-film device architecture that is compatible with flexible and lightweight PV. In this work, we present the first-ever 2T perovskite/CIS TSC with a power conversion efficiency (PCE) approaching 25% (23.5% certified, area 0.

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Lanthanide-based upconversion (UC) allows harvesting sub-bandgap near-infrared photons in photovoltaics. In this work, we investigate UC in perovskite solar cells by implementing UC single crystal BaF:Yb, Er at the rear of the solar cell. Upon illumination with high-intensity sub-bandgap photons at 980 nm, the BaF:Yb, Er crystal emits upconverted photons in the spectral range between 520 and 700 nm.

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