Publications by Hobeom Kim | EPFL Graph Search

Ultra-uniform perovskite crystals formed in the presence of tetrabutylammonium bistriflimide afford efficient and stable perovskite solar cells

Mohammad Khaja Nazeeruddin, Paul Joseph Dyson, Zhaofu Fei, Yong Ding, Jianxing Xia, Hiroyuki Kanda, Hobeom Kim, Jaekeun Lim, Alwani Imanah Rafieh

Compositional engineering of organic-inorganic metal halide perovskite allows for improved optoelectrical properties, however, phase segregation occurs during crystal nucleation and limits perovskite solar cell device performance. Herein, we show that by a ...

2024

Shallow-level defect passivation by 6H perovskite polytype for highly efficient and stable perovskite solar cells

Mohammad Khaja Nazeeruddin, Paul Joseph Dyson, Farzaneh Fadaei Tirani, Pascal Alexander Schouwink, Yong Ding, Hiroyuki Kanda, Hobeom Kim, So-Min Yoo

The power conversion efficiency of perovskite solar cells continues to increase. However, defects in perovskite materials are detrimental to their carrier dynamics and structural stability, ultimately limiting the photovoltaic characteristics and stability ...

Nature Research2024

Photonic nanostructures mimicking floral epidermis for perovskite solar cells

Mohammad Khaja Nazeeruddin, Hobeom Kim

Here, we report photonic nanostructures replicated from the adaxial epidermis of flower petals onto light-polymerized coatings using low-cost nanoimprint lithography at ambient temperature. These multifunctional nanocoatings are applied to confer enhanced ...

ELSEVIER2022

Employing 2D-Perovskite as an Electron Blocking Layer in Highly Efficient (18.5%) Perovskite Solar Cells with Printable Low Temperature Carbon Electrode

Mohammad Khaja Nazeeruddin, Hiroyuki Kanda, Hobeom Kim, So-Min Yoo, Jaekeun Lim, Dmitry Bogachuk

Interface engineering and passivating contacts are key enablers to reach the highest efficiencies in photovoltaic devices. While printed carbon-graphite back electrodes for hole-transporting material (HTM)-free perovskite solar cells (PSCs) are appealing f ...

WILEY-V C H VERLAG GMBH2022

Strain effects on halide perovskite solar cells

Mohammad Khaja Nazeeruddin, Ulf Anders Hagfeldt, Hobeom Kim, Bowen Yang, Jiajia Suo

Halide perovskite solar cells (PSCs) have achieved power conversion efficiencies (PCEs) approaching 26%, however, the stability issue hinders their commercialization. Due to the soft ionic nature of perovskite materials, the strain effect on perovskite fil ...

Royal Society of Chemistry2022

Asymmetrically Substituted 10H,10 ' H-9,9 '-Spirobi[acridine] Derivatives as Hole-Transporting Materials for Perovskite Solar Cells

Mohammad Khaja Nazeeruddin, Paul Joseph Dyson, Bin Ding, Jianxing Xia, Yi Zhang, Hiroyuki Kanda, Hobeom Kim, Nadja Isabelle Desiree Klipfel

Hole-transporting materials (HTMs) based on the 10H, 10 ' H-9,9 '-spirobi [acridine] core (BSA50 and BSA51) were synthesized, and their electronic properties were explored. Experimental and theoretical studies show that the presence of rigid 3,6-dimethoxy- ...

Wiley-VCH Verlag GmbH2022

Superhalogen Passivation for Efficient and Stable Perovskite Solar Cells

Mohammad Khaja Nazeeruddin, Hobeom Kim

Metal-halide perovskites are optoelectronic materials applied to solar cells as a light absorber due to their excellent optoelectronic properties. The power conversion efficiency of perovskite solar cells (PSCs) reaches 25.7% certified, which stands in com ...

WILEY-V C H VERLAG GMBH2022

Phase-Pure Quasi-2D Perovskite by Protonation of Neutral Amine

Mohammad Khaja Nazeeruddin, Hiroyuki Kanda, Hobeom Kim, Cansu Igci, So-Min Yoo, Marc Dessimoz

Phase control of low-dimensional metal-halide perovskites (LDPs) greatly affects their optoelectronic properties, and phase-pure LDPs are desirable to achieve efficient perovskite optoelectronic devices such as solar cells and light-emitting diodes. Herein ...

AMER CHEMICAL SOC2021

Piezo-electric and -phototronic effects of perovskite 2D|3D heterostructures

Mohammad Khaja Nazeeruddin, Hobeom Kim

Dimensionally-engineered perovskite heterostructures are highly attractive, as recently shown to be useful for enhancing the stability and efficiency in perovskite solar cells. Here, we first report piezo-electric and -phototronic effects found in two-dime ...

Elsevier2021

Advances in solution-processed near-infrared light-emitting diodes

Mohammad Khaja Nazeeruddin, Hobeom Kim

A summary of recent advances in the near-infrared light-emitting diodes that are fabricated by solution-processed means, with coverage of devices based on organic semiconductors, halide perovskites and colloidal quantum dots. ...

Nature Publishing Group2021