Department of Mechanical and Materials engineering

Nanomaterials, Organic Photovoltaic and Perovskite Solar Cell

Ph.D (Material Science), Indian Institute of Technology (IIT), Delhi, India 2015

(1) B. Tyagi, N. Kumar, H.B. Lee, Y.M. Song, S. Cho, J. Lee, J.-W. Kang* "Compact-Porous Hole-Transport-Layer for Highly Efficient Near-Infrared Region Transparent Perovskite Solar Cells for Tandem Applications" in submission (2022)

(2) M.M. Ovhal, H.B. Lee, S. Boud, K.-J. Ko, W.-Y. Jin, N. Kumar, B. Tyagi, J.-W. Kang* “Free-Standing, Stripe-Shaped Organic Solar Cells based on 3D-Printed Transparent Conducting Electrodes” Adv. Funct. Mat. in Submission (2022).

(3) H.B. Lee, N. Kumar, S. Cho, S. Hong, H.H. Lee, H.J. Kim, J.-S. Lee, J.-W. Kang* “Intercalation of Ammonium Cationic Ligands Enabled Grain Surface Passivation in Sequential-Deposited Perovskite Solar Cells” Adv. Energy & Sustainability Res in Revision (2022).

(4) H.B. Lee, R. Sahani, V. Devaraj, N. Kumar, B. Tyagi, J.-W. Oh, J.-W. Kang* “Complex Additive-Assisted Crystal Growth and Phase Stabilization of α-FAPbI3 Film for Highly Efficient, Air-Stable Perovskite Photovoltaics” Adv. Mater. Interface in Press (2022).

(5) S. He, H.B. Lee, N. Kumar, K.-J. Ko, M. Song, W. Kim, J.-W. Kang* "Realizing Full-color Perovskite Quantum Dots Light-Emitting Diodes via Contemporary Surface Ligand/Anion Engineering" Mat. Today Chem 26, 101012 (2022)

(6) B. Tyagi, H.B. Lee, N. Kumar, W.-Y. Jin, K.-J. Ko, M.M. Ovhal, R. Sahani, H.-J. Jung, J. Seo, J.-W. Kang* “High-performance, large-area semitransparent and tandem perovskite solar cells featuring highly scalable a-ITO/Ag mesh 3D top electrodes” Nano Energy 95, 106978 (2022).

(7) N. Kumar, H.B. Lee, R. Sahani, B. Tyagi, S. Cho, J.-S. Lee, J.-W. Kang* “Room-Temperature Spray Deposition of Large-area SnO2 Electron Transport Layer for High Performance, Stable FAPbI3-based Perovskite Solar Cells” Small Methods 6, 2101127 (2022).

(8) H.B. Lee, N. Kumar, V. Devaraj, K.-J. Ko, S. He, B. Tyagi, J.-W. Oh*, J.-W. Kang* “Trifluoromethyl-group bearing, hydrophobic bulky cations as defect passivators for highly efficient, stable perovskite solar cells” Solar RRL 5, 2000589 (2021).

(9) M.M. Ovhal, N. Kumar, H.B. Lee, B. Tyagi, K.-J. Ko, S. Boud, J.-W. Kang* “Roll-to-Roll 3D-Printing of Flexible, Transparent, All-Solid-State Supercapacitor” Cell Reports Physical Science 2, 100562 (2021).

(10) S. He, N. Kumar, H.B. Lee, K.-J. Ko, Y.-J. Jung, J.I. Kim, S. Bae, J.-H. Lee*, J.-W. Kang* “Tailoring the Refractive Index of CsPbBr3 Quantum Dots via Alkyl Cation-Engineering for Efficient Perovskite Light-Emitting Diodes” Chem. Eng. J. 425, 130678 (2021).

(11) H.B. Lee, N. Kumar, B. Tyagi, S. He, R. Sahani, J-W Kang* “Bulky Organic Cations Engineered Lead-halide Perovskites: A Review on Dimensionality and Optoelectronic Applications” Mat. Today Energy. 21, 100759 (2021).

(12) H.B. Lee, N. Kumar, B. Tyagi and J.-W. Kang* “Dimensionality and defect engineering using fluoroaromatic cations for efficiency and stability enhancement in perovskite photovoltaics” RRL Solar 5, 2000589 (2021).

(13) M.M. Ovhal, N. Kumar, S. Lim,* J.-W. Kang* “Large-Area (64 cm2), Semi-transparent, Flexible All-Solid-State Supercapacitor using D-Bar Coating Process” Appl. Surf. Sci. 529, 147072 (2020)

(14) H.B. Lee, N. Kumar, M.M. Ovhal, Y.J. Kim, Y.M. Song and J.-W. Kang* "Dopant-free, amorphous-crystalline heterophase SnO2 electron transport bilayer enables >20% efficiency in triple-cation perovskite solar cells" Adv. Funct. Mater. 30, 2001559 (2020).

(15) B.Tyagi, H.B. Lee, N. Kumar, and J.-W. Kang* "Double-halide interfacial engineered perovskite solar cells demonstrating outstanding performance and stability" ACS Appl. Energy Mater 3, 8595 (2020).

(16) H.B. Lee, W.-G. Kim, M. Lee, J.-M. Lee, S. He, N. Kumar, V. Devaraj, E.J. Choi, I. Jeon, M. Song, J.-W. Oh* and J.-W. Kang* "Gap-plasmon of virus-templated biohybrid nanostructures uplifting the performance of organic optoelectronic devices" Adv. Opt. Mater. 8, pp. 1902080 (2020)

(17) N. Kumar, H.B. Lee, S. Hwang and J.-W. Kang* "Large-area, green solvent spray deposited nickel oxide films for scalable fabrication of triple-cation perovskite solar cells" J. Mater. Chem. A 8, pp.3357 (2020).

(18) M.M. Ovhal, N. Kumar, S.-K. Hong, H.-W. Lee*, and J.-W. Kang* "Asymmetric supercapacitor featuring carbon nanotubes and nickel hydroxide grown on carbon fabric: A synergistic study on self-discharging characteristic" J. Alloys Compd. 828, 154447 (2020).

(19) H.B. Lee, M.-K. Jeon, N. Kumar, B. Tyagi, and J.-W. Kang* "Boosting the efficiency of SnO2-triple cation perovskite system beyond 20% using non-halogenated antisolvent" Adv. Funct. Mater. 29, 1903213 (2019).

(20based on metal mesh for organic optoelectronic device applications: A Review" J. Mater. Chem. C 7, pp.1087-1110 (2019).

(21) N. Kumar, H.B. Lee, S. Hwang, T.-W. Kim*, J.-W. Kang* "Fabrication of plasmonic gold-nanoparticle-transition metal oxides thin films for optoelectronic applications" J. Alloys Compd. 775, pp.39-50 (2019).

(22) K.-J. Ko, H.B. Lee, H.M. Kim, G.J. Lee, S.-R. Shin, N. Kumar, Y.M. Song*, J.-W. Kang*, "High-performance, color-tunable fiber shaped organic light-emitting diodes" Nanoscale 10, pp.16184-16192 (2018).

(23) N. Kumar, R.T. Ginting, J.-W. Kang* "Flexible, large-area, all-solid-state supercapacitors using spray deposited PEDOT:PSS/reduced-graphene oxide" Electrochimica Acta 270, pp.37-47 (2018).