Article
Engineering, Environmental
Gaoshuang He, Jie Li, Weixin Qiu, Long Chen, Keke Wang, Yang Liu, Min Liu, Wenzhang Li
Summary: To improve the PEC performance of α-SnWO4 photoanode, the atomic ratio of Sn and W on the surface is adjusted by exposing the photoanode to a Sn2+ or H+-rich microenvironment. Increasing the tin content on the surface facilitates charge separation and improves water oxidation reaction compared to the W atom. The tin-rich SnWO4 photoanode shows a 2-fold increase in photocurrent density compared to the tin-poor SnWO4 material, making it the state-of-the-art photocurrent density.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Nanoscience & Nanotechnology
Shankara S. Kalanur, Young Jae Lee, Hyungtak Seo
Summary: This study developed Pb-3[VO4](2) and PbV2O6 thin films for efficient and stable photoelectrochemical water splitting. Characterization showed that these films have suitable band edge positions for efficient reduction and oxidation. The optimized PbV2O6 thin films achieved a maximum photocurrent of 0.35 mA cm(-2), with stable production and high Faradaic efficiency for both O-2 and H-2.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Physical
Marwa Mohamed Abouelela, Go Kawamura, Wai Kian Tan, Atsunori Matsuda
Summary: By modifying ANP WO3 with Bi2S3 quantum dots, this study has successfully designed a photoanode with high current density and photoconversion efficiency, providing new insights and methods for the study of photoelectrochemical water splitting.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Chemistry, Physical
Shankara S. Kalanur, Young Jae Lee, Hyungtak Seo
Summary: The study introduces a versatile BiVO4 thin film synthesis strategy that allows for morphology tunability, feasibility of doping, and heterojunction formation in a single step. This strategy can be extended to fabricate different nanostructures by changing capping agents, and has shown the feasibility of Al doping and heterojunction formation with WO3 nanostructure for enhanced PEC activity. The proposed strategy could be exploited using new capping agents and dopants for simultaneously obtaining doped BiVO4 in heterojunction systems with unique morphology.
APPLIED SURFACE SCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Florin Andrei, Andreea Andrei, Ruxandra Birjega, Eduard Nicolae Sirjita, Alina Irina Radu, Maria Dinescu, Valentin Ion, Valentin-Adrian Maraloiu, Valentin Serban Teodorescu, Nicu Doinel Scarisoreanu
Summary: The study focused on the n-type tungsten oxide (WO3) semiconductor as a suitable photoanode for water decomposition reaction due to its physical and chemical properties. The research investigated the impacts of structural and optical changes in WO3 thin films on their photoelectrochemical PEC water-splitting properties. Results revealed that WO3 thin film prepared with a laser emitting at 355 nm wavelength exhibited the highest photocurrent density in acidic solution.
Article
Materials Science, Multidisciplinary
Wen Lei, Yingjie Yu, Haijun Zhang, Quanli Jia, Shaowei Zhang
Summary: This paper summarizes recent developments in using various techniques to introduce, characterize, and regulate defects in defect engineering. The important role of defects in high-performance defect engineered photoelectrodes for PEC water splitting application is highlighted. Current challenges and future perspectives in the field of defect engineering of nanostructures for photoelectrodes are also discussed.
Article
Chemistry, Physical
Mauricio A. Melo, Igor M. Brito, Joao V. S. B. Mello, Pamela S. M. Rocha, Isabela A. A. Bessa, Braulio S. Archanjo, Fabio S. Miranda, Ricardo J. Cassella, Celia M. Ronconi
Summary: Producing solar fuels through semiconductor-based photocatalytic water splitting is a promising solution for global adoption of renewable energy sources. This study introduces a simple method for preparing nanostructured hematite and niobium-doped hematite nanoparticles, which can be assembled into thin films for use as photoanodes in photoelectrochemical cells. The optimization of film composition and thickness significantly improves the photocurrent and enhances the efficiency of water splitting, making these materials more economically competitive.
Article
Chemistry, Physical
Shrinath Dattatray Ghadge, Moni K. Datta, Oleg Velikokhatnyi, Prashant N. Kumta
Summary: This study presents a simple and effective Mo doping approach for generating high-performance photoanodes for PEC water splitting. Mo doping can enhance light absorption ability, reduce band gap, increase carrier density and photocurrent density, while also decreasing charge transfer resistance and improving PEC stability.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Thanh Tam Thi Tran, Sohyeon Kim, Jeongsuk Seo
Summary: This study demonstrates the size dependence of perovskite-type BaNbO2N particles on the photoelectrochemical (PEC) water splitting activity. The size of Ba5Nb4O15 particles, which are precursor oxides for BaNbO2N synthesis, was dependent on the calcination temperature. The reduction in size of oxynitride particles greatly improved the PEC water splitting activity.
JOURNAL OF CATALYSIS
(2022)
Article
Electrochemistry
Tao Wang, Xiaoli Fan, Bin Gao, Cheng Jiang, Yang Li, Peng Li, Songtao Zhang, Xianli Huang, Jianping He
Summary: In this study, CuWO4-based films were prepared using a one-step hydrothermal method, leading to CuWO4/WO3 heterojunctions with urchin-like nanoarray morphology. The optimized film exhibited significantly improved photoelectrochemical performance due to its unique structure and efficient charge separation.
Article
Chemistry, Physical
Weiwei Xu, Wei Tian, Linxing Meng, Fengren Cao, Liang Li
Summary: Introducing In-O-Cd bond at the interface of ZnIn2S4/CdS heterojunction successfully converts the band structure and accelerates surface reaction kinetics, resulting in enhanced PEC performance.
ADVANCED ENERGY MATERIALS
(2021)
Article
Chemistry, Physical
Shankara S. Kalanur, Hyungtak Seo
Summary: The influence of Nb doping on the photoelectrochemical water splitting activity of BiVO4 photoanode is explored. Experimental and theoretical studies show that Nb doping enhances the photocurrent density, charge separation efficiency, and charge transfer capability of BiVO4, leading to efficient H-2/O-2 evolution.
JOURNAL OF CATALYSIS
(2022)
Article
Chemistry, Physical
Yuhei Taga, Zhenhua Pan, Kenji Katayama, Woon Yong Sohn
Summary: Developing an efficient photoanode is crucial for sustainable hydrogen energy production. By constructing a solid-state junction and applying an inverse opal structure, a BiVO4/WO3-IO photoanode was developed and demonstrated better performance in photoelectrochemical water splitting compared to a bare WO3 photoanode. This successful combination provides a promising approach for utilizing solar energy in visible-light-responsive photoanodes.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Wenrui Lin, Boyang Zhang, Kaiwei Liu, Jifang Zhang, Jiaming Wang, Guijun Ma
Summary: By controlling the orientation of crystal facets and depositing gold along the edges, the photoelectrochemical performance of WO3 photoanodes for water splitting can be significantly improved.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Physical
Burcu Oral, Elif Can, Ramazan Yildirim
Summary: In this study, machine learning techniques were used to analyze an extensive dataset on photoelectrochemical water splitting over n-type semiconductors. The results showed that association rule mining, decision tree, and random forest could identify patterns and establish relations between photocurrent density and various descriptors.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Materials Science, Multidisciplinary
Ranveer Singh, Qadeer Akbar Sial, Seung-ik Han, Sanghee Nah, Ji-Yong Park, Hyungtak Seo
Summary: The study effectively utilized hot-carriers at the nanoscale and their transfer dynamics from a non-noble metal to a metal oxide interface through real-space photocurrent mapping using local probe techniques and femtosecond transient absorption measurements. The results showed that hot carriers were injected into the metal oxide layer from the TiN layer, indicating efficient electron transfer between the layers and achieving high conversion efficiency for optoelectronic devices.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2022)
Article
Nanoscience & Nanotechnology
Hojun Seo, Sang Yeon Lee, Jeongsu Lee, Sunjin Kim, Onejae Sul, Hyungtak Seo, Seung-Beck Lee
Summary: A low-temperature process is demonstrated to transform insulating In2O3 thin-films into n-type semiconductors, enabling the development of high-performance In2O3 thin-film transistors. The H-plasma assisted annealing process, compared to thermal annealing, not only reduces processing time but also maintains the insulating nature of the untreated area.
Article
Chemistry, Multidisciplinary
Mohit Kumar, Yeong Hwan Ahn, Shahid Iqbal, Unjeong Kim, Hyungtak Seo
Summary: Emerging nonvolatile resistive switching, or memristors, rely on the composition change of active materials rather than storing charge. By stabilizing the conduction channel through manipulation of oxygen defects using electron-beam irradiation, high-performance memristor devices with adjustable switching ratios are fabricated, showcasing broad modulation of neural activities.
Article
Nanoscience & Nanotechnology
Qadeer Akbar Sial, Mohit Kumar, Shahid Iqbal, Shankara S. Kalanur, Hyungtak Seo
Summary: In this study, an acid-sensitive artificial nociceptor device is developed for electronic nose application, which can detect acid concentration and generate synaptic signals, demonstrating memory storage ability and tunability.
ADVANCED ELECTRONIC MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Le Thai Duy, Qadeer Akbar Sial, Hyungtak Seo
Summary: The study focused on utilizing a stretchable composite based on carbon nanotubes and polydimethylsiloxane for textile-based supercapacitors, exploring the positive and negative effects of washing. Strategies utilizing molybdenum trioxide nanoflakes were designed to enhance the composite's performance, showing potential for improved energy and power densities. Additionally, chemical treatment with a liquid detergent was found to significantly enhance the performance of supercapacitor electrodes.
ADVANCED MATERIALS TECHNOLOGIES
(2022)
Article
Chemistry, Multidisciplinary
Eunji Ji, Jong Hun Kim, Wanggon Lee, June-Chul Shin, Hyungtak Seo, Kyuwook Ihm, Jin-Woo Park, Gwan-Hyoung Lee
Summary: Transition metal dichalcogenides (TMDs) are promising candidates for the semiconductor industry due to their superior electrical properties. This study demonstrates the XeF2-mediated surface oxidation of 2H-MoTe2 to form a thin and uniform oxidized layer, which helps reduce contact resistance and improve field-effect hole mobility. The work provides a straightforward and effective method for 2D electronics.
NANOSCALE ADVANCES
(2022)
Article
Chemistry, Multidisciplinary
Sang Eun Yoon, Bomi Kim, So Yeon Chun, Sang Yeon Lee, Dohyeon Jeon, Minju Kim, Solin Lee, Bo Eun Seo, Kang Suh Choi, Felix Sunjoo Kim, Taekyeong Kim, Hyungtak Seo, Kyungwon Kwak, Jong H. Kim, BongSoo Kim
Summary: The study investigated the impact of molecular weight of conjugated polymers (CPs) on doping efficiency, electrical conductivity, and thermoelectric properties. Findings indicated that high molecular weight CPs tend to have higher carrier mobility and potential for maximal power generation.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Mohit Kumar, Unjeong Kim, WangGon Lee, Hyungtak Seo
Summary: This study presents a novel ReTFT memory that achieves high-speed and programmable multilevel storage, providing a solution for hardware implementation of in-memory computing. Additionally, various signal memory-processing operations are explored, offering potential applications in neuromorphic hardware.
ADVANCED MATERIALS
(2022)
Article
Chemistry, Physical
Ranveer Singh, Hyunwoo Kang, Heechul Shin, Ji-Yong Park, Hyungtak Seo
Summary: The study investigated the 2DEG phenomenon at the interface of an amorphous-Al2O3-In2O3-amorphous-Al2O3 (AIA) heterostructure on a flexible substrate, showing promising opportunities for flexible oxide electronics. The AIA device exhibited a high stability with outstanding performance, and maintained good flexibility even after bending tests.
APPLIED SURFACE SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
HanJin Lim, Jae Hyoung Choi, Gihee Cho, Jaewan Chang, Younsoo Kim, Hyung-Suk Jung, Kyoung-Sub Shin, Hyungtak Seo, Hyeongtag Jeon
Summary: The interface between a dielectric thin film and a metal electrode is studied to improve reliability and electrical properties of the metal-insulator-metal (MIM) capacitor in dynamic random-access memory (DRAM) devices. The interfacial layers between the dielectric thin film and the metal electrode play an important role in controlling the dielectric loss of MIM capacitors through band engineering, lattice modification, or dipole formation. By properly combining interfacial layers, a robust MIM capacitor for DRAM is realized with low leakage current and improved reliability.
ADVANCED MATERIALS TECHNOLOGIES
(2022)
Article
Materials Science, Ceramics
Heecheol Shin, Hyobin Choi, Jaeseong Lim, Wanggon Lee, Kumar Mohit, Younsoo Kim, Hyung-Suk Jung, Hanjin Lim, Hyungtak Seo
Summary: The shrinkage and leakage current suppression of MIM capacitors are crucial for maintaining desired charge storage and retention levels in DRAM. This study uses ARXPS, SE, and temperature dependent I-V analysis to analyze a ZrO2-based dielectric film and its interface with a TiO2/Al2O3 buffer layer, demonstrating the importance of the buffer layer in controlling leakage current.
JOURNAL OF ASIAN CERAMIC SOCIETIES
(2022)
Article
Chemistry, Multidisciplinary
Shankara S. Kalanur, Young Jae Lee, Hyungtak Seo
Summary: In this study, a multijunction strategy with stoichiometrically engineered hole extraction layer and efficient, non-toxic MoOx catalyst layer sandwiched in Cu2O photocathode was proposed for enhanced charge separation and stable H2 production. The optimized multijunction system achieved high photocurrent and significant anodic shift in noble metal-free Cu2O photocathodes.
MATERIALS TODAY CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Arumugam Sivanantham, Hansung Lee, Sung Won Hwang, Han Uk Lee, Sung Beom Cho, Byungmin Ahn, In Sun Cho
Summary: This study investigates the active role of vanadium in improving the electrocatalytic activity for the hydrogen evolution reaction in VxCuCoNiFeMn (x = 0, 0.5, and 1.0) high entropy alloys. The incorporation of vanadium enhances the electrical conductivity and electrochemical surface area of the alloy, leading to improved kinetics for the reaction. The findings can contribute to the development of highly active high entropy alloys for large-scale electrochemical water splitting.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Review
Chemistry, Multidisciplinary
Balasubramanian Jansi Rani, Arumugam Sivanantham, In Sun Cho
Summary: This review summarizes the impact of nanostructured morphologies on the electrochemical performance of spinel manganates. It is found that nanostructured spinel manganates with preferred A-site cation significantly improve the thermodynamics and electrochemical reaction kinetics at solid-liquid and solid-solid interfaces. Particularly, the faceted, hollow, 1D nanostructured CoMn2O4 and its nanocomposites exhibit outstanding electrochemical performance. Feasible methods of synthesizing AMO nanostructures and nanocomposites are also discussed in this review. These insights are expected to contribute to the development of efficient electrode materials for energy conversion and storage devices.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Youngho Kim, Noeul Kim, Sang Hoon Lee, Seok-Ki Hyeong, Jae-Hyun Lee, Jaeyeong Lee, Jong Seong Bae, In Sun Cho, Jae-Young Choi, Soo Young Kim, Hak Ki Yu
Summary: The development of technologies for electromagnetic wave contamination has attracted attention. For high frequencies such as those in the K and K-a ranges, there is a limitation in using only one material. To address this, it is necessary to increase the absorption coefficients by increasing the path of electromagnetic waves using internal scattering. This study accurately demonstrated the role of Sn in the growth of indium tin oxide (ITO) nano-branch structure, resulting in high-density ITO nano-branches with the thinnest possible thickness. With shielding efficiencies of 21.09 dB (K band) and 17.81 dB (K-a band), it is expected to be applied in various fields due to its high specific shielding efficiency, low thickness, and weight.
