Unraveling Hydride-Driven Multiphasic Reduction Toward Tunable Germanium Structures for Lithium-Ion Batteries Gijung Lee, Jieun Kang, Jin Yong Kwon, Woori Bae, Noh‐Moon Lee, et al. Advanced Science, 2026 Germanium (Ge) stands out as a promising anode due to its high theoretical capacity combined with intrinsically superior ionic and electronic conductivities. Nevertheless, the high cost and pronounced volume expansion upon lithiation pose significant challenges for its practical implementation. Herein, sodium hydride (NaH)‐driven multiphasic reduction is introduced to synthesize micrometre Ge with a tailored porous and hybrid nanocrystalline‐amorphous structure, which uniquely emerges under off‐stoichiometric reduction conditions. By elucidating the underlying multiphase reaction pathways, this structural evolution can be attributed to the dual role of NaH decomposition, where hydrogen regulates porosity and crystallinity while metallic Na acts as the primary reductant for germanium dioxide. This synthesized Ge exhibits outstanding reversibility and an exceptionally cycling stability even at high current density compared to commercial Ge microparticles, while also preserving the electrode integrity throughout cycling. This study offers mechanistic insights into extending NaH‐driven reduction beyond GeO 2 to other metal oxides, paving the way for the development of high‐capacity anodes.
Effect of Atomic Layer Deposition of Ultra-Thin Oxide on Reactivity and Durability of Perovskite Oxygen Electrodes Jongsu Seo, SungHyun Jeon, Hyunseung Kim, San Kwak, DongHwan Oh, et al. Advanced Materials, 2026 Conductive perovskite oxides (ABO 3 ) are key oxygen electrode materials for energy conversion applications, but they suffer from irreversible performance degradation at elevated temperatures due to surface chemical instability. In this study, we investigate how the surface chemical environment and oxygen exchange kinetics of thin‐film La 0.6 Sr 0.4 CoO 3 are affected by the atomic layer deposition of binary oxides—specifically HfO 2 and Al 2 O 3 . We observe that both HfO 2 and Al 2 O 3 overcoats successfully maintain the rapid oxygen exchange rate on the electrode surface. Interestingly, however, their effects on the electrode surface chemistry differ significantly, as do the ideal coating thicknesses, as revealed by X‐ray photoelectron spectroscopy, secondary ion mass spectrometry, and transmission electron microscopy analyses. These findings suggest two distinct mechanisms for stabilizing the perovskite surface: the oxide overcoats (1) reduce oxygen vacancies that attract Sr ions to the surface and (2) act as a scavenger, consuming excess surface Sr, and suggest the design principle of a new strategy based on atomic layer deposition to improve perovskite surface durability.
Designing Supported Nanoparticles via Synergistic Ex-Solution and Phosphorization for Tailored Active Site Generation Jun Kyu Kim, Sangwoo Kim, Yong Beom Kim, Bonjae Koo, DongHwan Oh, et al. Advanced Materials, 2025 Supported nanoparticles incorporating catalytically attractive nonmetal elements have gained significant attention as a promising strategy for enhancing catalytic activity in various industrial applications. This study presents an innovative one‐pot synthesis method for fabricating hybrid catalysts, which simultaneously modifies surface properties through the precipitation of nanoparticles with the concurrent incorporation of nonmetal elements. The underlying concept is to synchronize the temperature required for particle formation with that of nonmetal incorporation by adjusting the oxygen chemical potential of the host oxide. As a case study, Ir‐ and Ru‐doped WO3 are selected as the starting material, with phosphorus (P) as the representative nonmetal for surface functionalization. Notably, the hybrid catalyst, composed of amorphous (Ir,Ru)Px particles dispersed on P‐rich WO2.9 sheets, is synthesized through a single heat treatment at 500 °C, avoiding undesirable sintering of the host material. When used as a hydrogen evolution catalyst, this material exhibits outstanding mass activity, durability, compared to state‐of‐the‐art Pt/C catalysts. Density functional theory calculations further reveal that the superior performance of the hybrid catalysts attributes to improved water dissociation and favorable adsorption and desorption of key reaction intermediates. This novel synthesis strategy offers considerable potential for advancing diverse areas of heterogeneous catalysis.
An Ideal Surface Reveals How Active It Is and Why It Degrades: SrTi 0.5 Fe 0.5 O 3−δ Model Thin Film with Atomically Flat Terraces─A Case Study H Kim, J Liu, K Jang, B Koo, JK Kim, J Seo, C Jung, PP Choi, F Ciucci, ... Journal of the American Chemical Society , 2026 2026
Cesium-Promoted Nickel-Ceria Anodes for Enhanced Stability and Performance in Low-Temperature Solid Oxide Fuel Cells DK Lim, J Kim, S Nam, B Koo, JH Kim, B Jeong, Y Choi, WC Jung ACS nano , 2026 2026 Citations: 2
Anchored nanocatalysts enable efficient oxygen reduction in barium cobaltite cathodes IS Lim, HS Yoo, DH Oh, G Heo, S Oh, B Koo, W Lee, JH Kim Nanoscale 18 (17), 9444-9452 , 2026 2026
Unraveling Hydride‐Driven Multiphasic Reduction Toward Tunable Germanium Structures for Lithium‐Ion Batteries G Lee, J Kang, JY Kwon, W Bae, NM Lee, B Park, Y Park, C Sun, J Yoon, ... Advanced Science, e74278 , 2026 2026 Citations: 1
Effect of Atomic Layer Deposition of Ultra‐Thin Oxide on Reactivity and Durability of Perovskite Oxygen Electrodes J Seo, SH Jeon, H Kim, S Kwak, DH Oh, B Koo, J Kim, JH Kim, WC Jung Advanced Materials, e13655 , 2026 2026
Hollow Bi 2 Te 3 nanowire supported Ir for highly active and durable oxygen evolution reaction in proton exchange membrane water electrolysis YH Yun, KS Yoon, S Byun, HJ Park, G Doo, SK Kim, MJ Kim, HS Cho, ... Nano Research 18 (11), 94908097 , 2025 2025 Citations: 2
Oxide-Type Materials for Catalytic CO 2 Methanation: Recent Advances and Future Perspectives: Oxide-Type Materials for Catalytic B Koo Korean Journal of Chemical Engineering 42 (13), 3153-3172 , 2025 2025 Citations: 1
Promotion of Reversible Fuel-Power Generation in Protonic Ceramic Electrochemical Cell via Water-Mediated Ex-Solution S Ahn, D Kim, I Jeong, HC Kang, IS Lim, G Heo, DK Lim, JK Kim, KM Roh, ... ACS Energy Letters 10 (10), 4948-4956 , 2025 2025 Citations: 4
Ni–deficient NiO/downsized RuO2 composite catalyst with rivalrous size evolution for rechargeable Li–CO2 batteries DK Boo, H Kim, SJ Kwak, HJ Lee, Y Lim, Y Yoo, H Park, J Tak, JH Lee, ... Composites Part B: Engineering, 113004 , 2025 2025 Citations: 2
Suppressing grain growth and thermo-chemical decomposition of perovskite oxide nanoparticles via B-site cation surface stabilization N Tsvetkov, HG Seo, J Seo, B Koo, H Kim, KH Kim, S Ahn, JK Kang, ... Chemical Engineering Journal, 168008 , 2025 2025 Citations: 2
Designing Supported Nanoparticles via Synergistic Ex‐Solution and Phosphorization for Tailored Active Site Generation JK Kim, S Kim, YB Kim, B Koo, DH Oh, H Kim, K Kim, JW Han, WC Jung Advanced Materials 37 (26), 2417576 , 2025 2025 Citations: 4
Enhanced Alkaline Water Electrolysis by the Rational Decoration of RuO x with the In Situ-Grown CoFe Nanolayer S Kim, J Lee, YB Kim, DH Oh, JK Kim, B Koo, H Kim, G Jung, MJ Kim, ... ACS nano 19 (10), 10026-10037 , 2025 2025 Citations: 5
Tuning Intrinsic Traits of Carbon Nanofibers for Advanced Nonaqueous Li–CO 2 Batteries HJ Lee, H Kim, YJ Yoo, S Lee, SH Cho, B Koo, MS Kim, JS Nam, W Choi, ... International Journal of Energy Research 2025 (1), 4052225 , 2025 2025 Citations: 2
Performance enhancement of rechargeable zinc-air battery through synergistic ex-solution of multi-component Pt/CoWO4-x catalysts C Lee, CK Hwang, JW An, JS Jang, B Koo, JM Kim, K Shin, CS Lee, ... Applied Catalysis B: Environment and Energy 358, 124371 , 2024 2024 Citations: 10
Improvement of Mass Activity of IrO x Electrocatalyst in Acidic Oxygen Evolution Reaction Using Bi 3 TaO 7 Support YH Yun, C Lee, B Koo Electrochemical Society Meeting Abstracts prime2024, 2786-2786 , 2024 2024
Concurrent Amorphization and Nanocatalyst Formation in Cu‐Substituted Perovskite Oxide Surface: Effects on Oxygen Reduction Reaction at Elevated Temperatures (Adv. Mater. 40/2024) SH Jeon, WG Jung, H Bae, S Ahn, B Koo, WJ Yu, S Kim, DH Oh, U Kim, ... Advanced Materials 36 (40), 2470318 , 2024 2024
Concurrent Amorphization and Nanocatalyst Formation in Cu‐Substituted Perovskite Oxide Surface: Effects on Oxygen Reduction Reaction at Elevated Temperatures SH Jeon, WG Jung, H Bae, S Ahn, B Koo, WJ Yu, S Kim, DH Oh, U Kim, ... Advanced Materials 36 (40), 2404103 , 2024 2024 Citations: 16
Development of Ba 3 TiO 7 -Supported IrO x Electrocatalysts for Enhanced Mass Activity in the Acidic Oxygen Evolution Reaction CH Lee, B Koo, S Lee, MJ Kim, G Doo, H Park, H Cho Electrochemical Society Meeting Abstracts 245, 1755-1755 , 2024 2024
Rapid and ultrahighly sensitive ethanol sensing in p-type SrTi1‐xFexO3 SH Cho, MJ Choi, B Koo, J Kim, TH Lee, JM Suh, TH Eom, SY Park, T Kim, ... Sensors and Actuators B: Chemical 403, 135137 , 2024 2024 Citations: 18
An Ideal Surface Reveals How Active It Is and Why It Degrades: Atomically Flat SrTi0. 5Fe0. 5O3-δ Model Thin Film–a Case Study WC Jung, H Kim, J Liu, K Jang, B Koo, JK Kim, J Seo, C Jung, PP Choi, ... 2024
MOST CITED SCHOLAR PUBLICATIONS
A highly cross-linked polymeric binder for high-performance silicon negative electrodes in lithium ion batteries B Koo, H Kim, Y Cho, KT Lee, NS Choi, J Cho Angewandte Chemie-International Edition 51 (35), 8762-8767 , 2012 2012 Citations: 991
Magnesium (II) bis (trifluoromethane sulfonyl) imide-based electrolytes with wide electrochemical windows for rechargeable magnesium batteries SY Ha, YW Lee, SW Woo, B Koo, JS Kim, J Cho, KT Lee, NS Choi ACS applied materials & interfaces 6 (6), 4063-4073 , 2014 2014 Citations: 548
Sr segregation in perovskite oxides: why it happens and how it exists B Koo, K Kim, JK Kim, H Kwon, JW Han, WC Jung Joule 2 (8), 1476-1499 , 2018 2018 Citations: 544
Enhanced oxygen exchange of perovskite oxide surfaces through strain-driven chemical stabilization B Koo, H Kwon, YJ Kim, HG Seo, JW Han, WC Jung Energy & Environmental Science 11 (1), 71-77 , 2018 2018 Citations: 124
Growth Kinetics of Individual Co Particles Ex-solved on SrTi 0.75 Co 0.25 O 3-δ Polycrystalline Perovskite Thin Films YR Jo, B Koo, MJ Seo, JK Kim, S Lee, K Kim, JW Han, WC Jung, BJ Kim Journal of the American Chemical Society 141 (16), 6690-6697 , 2019 2019 Citations: 109
An universal oxygen electrode for reversible solid oxide electrochemical cells at reduced temperatures JH Kim, D Kim, S Ahn, KJ Kim, SH Jeon, DK Lim, JK Kim, U Kim, HN Im, ... Energy & Environmental Science 16 (9), 3803-3814 , 2023 2023 Citations: 91
Control of transition metal–oxygen bond strength boosts the redox ex-solution in a perovskite oxide surface K Kim, B Koo, YR Jo, S Lee, JK Kim, BJ Kim, WC Jung, JW Han Energy & Environmental Science 13 (10), 3404-3411 , 2020 2020 Citations: 76
Exceptional tunability over size and density of spontaneously formed nanoparticles via nucleation dynamics JK Kim, YR Jo, S Kim, B Koo, JH Kim, BJ Kim, WC Jung ACS applied materials & interfaces 12 (21), 24039-24047 , 2020 2020 Citations: 41
Highly Durable C 2 Hydrocarbon Production via the Oxidative Coupling of Methane Using a BaFe 0.9 Zr 0.1 O 3−δ Mixed Ionic and Electronic Conducting Membrane and La 2 O … G Dimitrakopoulos, B Koo, B Yildiz, AF Ghoniem ACS Catalysis 11 (6), 3638-3661 , 2021 2021 Citations: 38
Isovalent doping: a new strategy to suppress surface Sr segregation of the perovskite O 2-electrode for solid oxide fuel cells B Koo, J Seo, JK Kim, WC Jung Journal of Materials Chemistry A 8 (27), 13763-13769 , 2020 2020 Citations: 35
Effect of a novel amphipathic ionic liquid on lithium deposition in gel polymer electrolytes NS Choi, B Koo, JT Yeon, KT Lee, DW Kim Electrochimica acta 56 (21), 7249-7255 , 2011 2011 Citations: 35
Vinylene carbonate and tris (trimethylsilyl) phosphite hybrid additives to improve the electrochemical performance of spinel lithium manganese oxide/graphite cells at 60° C B Koo, J Lee, Y Lee, JK Kim, NS Choi Electrochimica Acta 173, 750-756 , 2015 2015 Citations: 34
Tris (pentafluorophenyl) borane-containing electrolytes for electrochemical reversibility of lithium peroxide-based electrodes in lithium–oxygen batteries NS Choi, G Jeong, B Koo, YW Lee, KT Lee Journal of power sources 225, 95-100 , 2013 2013 Citations: 34
Robust nano-architectured composite thin films for a low-temperature solid oxide fuel cell cathode HG Seo, Y Choi, B Koo, A Jang, WC Jung Journal of Materials Chemistry A 4 (24), 9394-9402 , 2016 2016 Citations: 32
Understanding and mitigating A-site surface enrichment in Ba-containing perovskites: A combined computational and experimental study of BaFeO 3 J Liu, JK Kim, Y Wang, H Kim, A Belotti, B Koo, Z Wang, WC Jung, ... Energy & Environmental Science 15 (10), 4069-4082 , 2022 2022 Citations: 29
Controlling the size of Pt nanoparticles with a cationic surfactant, C n TABr J Seo, S Lee, B Koo, WC Jung CrystEngComm 20 (14), 2010-2015 , 2018 2018 Citations: 26
Study of the surface reaction kinetics of (La, Sr) MnO 3− δ oxygen carriers for solar thermochemical fuel production YJ Kim, SJ Jeong, B Koo, S Lee, NW Kwak, WC Jung Journal of Materials Chemistry A 6 (27), 13082-13089 , 2018 2018 Citations: 23
Sintering-resistant platinum electrode achieved through atomic layer deposition for thin-film solid oxide fuel cells HG Seo, S Ji, J Seo, S Kim, B Koo, Y Choi, H Kim, JH Kim, TS Kim, ... Journal of Alloys and Compounds 835, 155347 , 2020 2020 Citations: 22
Rapid and ultrahighly sensitive ethanol sensing in p-type SrTi1‐xFexO3 SH Cho, MJ Choi, B Koo, J Kim, TH Lee, JM Suh, TH Eom, SY Park, T Kim, ... Sensors and Actuators B: Chemical 403, 135137 , 2024 2024 Citations: 18
Concurrent Amorphization and Nanocatalyst Formation in Cu‐Substituted Perovskite Oxide Surface: Effects on Oxygen Reduction Reaction at Elevated Temperatures SH Jeon, WG Jung, H Bae, S Ahn, B Koo, WJ Yu, S Kim, DH Oh, U Kim, ... Advanced Materials 36 (40), 2404103 , 2024 2024 Citations: 16
