Article
Physics, Applied
Yuli Ma, Yun Hang Hu
Summary: Surface Cu2+ dopants on WO3 photoanodes, created using a simple hydrothermal method, significantly improve the interface charge transfer efficiency and act as adsorption and activation sites for intermediate species, decreasing Gibbs free energy and enhancing the oxygen evolution reaction activity. This leads to a 600% increase in incident-photon-to-current conversion efficiency under specific light irradiation and bias conditions.
APPLIED PHYSICS LETTERS
(2021)
Article
Chemistry, Physical
Yan Li, Qiong Mei, Zejun Liu, Xingsheng Hu, Zhaohui Zhou, Jingwei Huang, Bo Bai, Hui Liu, Fei Ding, Qizhao Wang
Summary: In this study, the performance of WO3 as a photoanode was improved by doping with F and preparing F:FeOOH/BiVO4/WO3 composite photoanodes. The composite photoanodes exhibited significantly enhanced photocurrent and showed good stability and electron lifetime. Additionally, F-doped FeOOH showed better catalytic performance than FeOOH. This work may have important implications for the application of photocatalysts in PEC water splitting.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2022)
Article
Chemistry, Physical
Shankara S. Kalanur, Ranveer Singh, Hyungtak Seo
Summary: Doping WO3 with Y can improve its surface charge characteristics, increase photocurrent and oxygen production efficiency, resulting in a more efficient photoelectrochemical water splitting process.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2021)
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
Chau Thi Thanh Thuy, Gyuho Shin, Lee Jieun, Hyung Do Kim, Ganesh Koyyada, Jae Hong Kim
Summary: In this study, self-doped carbon dots with nitrogen elements (NCD) were successfully prepared using L-histidine as a precursor through a simple one-pot hydrothermal carbonization method. The effect of NCDs on photoelectrochemical (PEC) water splitting was investigated by decorating NCDs on TiO2 nanorods. The results showed improved PEC performance with the introduction of NCDs on TiO2.
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
Chemistry, Physical
Jingyi Lin, Xiujun Han, Siyuan Liu, Ying Lv, Xin Li, Yixin Zhao, Yao Li, Lianzhou Wang, Shenmin Zhu
Summary: This study presents a method to enhance the photocurrent density of bismuth vanadate (BiVO4) photoanodes using a nitrogen-doped cobalt-iron oxide (N-CFO) cocatalyst layer. The N-CFO/BVO photoanode shows higher photocurrent density compared to pure BVO and CFO/BVO with oxygen vacancies. Mechanism studies reveal that nitrogen dopants improve the electrical conductivity and reaction activity of cobalt-iron oxide. This work provides a novel strategy for designing efficient and cheap cocatalysts for photoanodes using Prussian blue analogues.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2023)
Article
Chemistry, Physical
Muhammad Asim Mushtaq, Anuj Kumar, Ghulam Yasin, Muhammad Arif, Mohammad Tabish, Shumaila Ibraheem, Xingke Cai, Wen Ye, Xiaoyu Fang, Ali Saad, Jie Zhao, Shengfu Ji, Dongpeng Yan
Summary: In this study, low-cost Mo-doped WO3@CdS porous hollow microspheres were synthesized and demonstrated as efficient catalysts for reducing gaseous N-2 into ammonia. The Mo-doping and interconnected porous heterostructures provide sufficient catalytic sites for effective photoelectrocatalytic N-2 reduction.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2022)
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
Shouli Bai, Yanling Fang, Yingying Zhao, Yongjun Feng, Ruixian Luo, Dianqing Li, Aifan Chen
Summary: The novel ternary photoanode was prepared by modifying Bi nanoparticles on the type II heterojunction of WO3-ZnWO4 using drop casting and chemical impregnation methods. The photocurrent density of the ternary photoanode reached 3.0 mA/cm2 at 1.23 V (vs. RHE), which is 6 times higher than the WO3 photoanode. The incident photon-to-electron conversion efficiency (IPCE) at 380 nm wavelength increased by 2.8 times compared to the WO3 photoanode, thanks to the formation of a type II heterojunction and the modification of Bi NPs, resulting in enhanced light capture ability and improved carrier separation efficiency.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Chemistry, Physical
Fatma Zakaria Salem, M. A. Ahmed, M. A. Sadek, Maryam G. Elmahgary
Summary: This study investigates the controllable properties of SrSnO3 perovskite as a catalyst for photocatalytic water splitting using computational analysis. The synergistic effect of hydrogen doping and oxygen vacancies on the optoelectronic properties is discussed. The results show that interstitial hydrogen defects introduce shallow defect states and increase the dielectric constant, while the HOV-OV structural configuration significantly enhances optical absorption and permittivity at high concentrations of oxygen vacancies, making it an ideal catalyst for photocatalytic water splitting.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Lei Jin, Haiguang Zhao, Zhiming M. Wang, Federico Rosei
Summary: This article summarizes the latest progress in tailoring the materials, structure, and performance of QDs-based PEC H-2 generation, and discusses the impact of specific features of QDs and charge generation and transfer on the performance of PEC devices. Future challenges and opportunities for high-efficiency and stable QDs-based PEC applications are also discussed.
ADVANCED ENERGY MATERIALS
(2021)
Article
Chemistry, Physical
Heng Wu, Qi Liu, Li Zhang, YaWen Tang, Gang Wang, GuoBing Mao
Summary: A simple hydrothermal method has been developed to prepare a WO3 nanorod array@Prussian blue (WO3@PB) composite material with core-shell heterogeneous structures, which showed higher photocurrent density compared to pure WO3. The composite material offers a promising photoelectrocatalyst for water decomposition applications and provides a way for the synthesis of environmentally friendly and low-cost photoanode materials.
ACS APPLIED ENERGY MATERIALS
(2021)
Article
Chemistry, Applied
Wen Zhang, Meng Tian, Haimiao Jiao, Hai-Ying Jiang, Junwang Tang
Summary: In this work, a highly-matched BiVO4/WO3 nanobowl photoanode was constructed and further modified to enhance its photocurrent density and photoelectrochemical performance. The photocurrent density was increased by about 5-fold compared to pristine BiVO4, achieving a faradaic efficiency of approximately 95%.
CHINESE JOURNAL OF CATALYSIS
(2022)
Article
Energy & Fuels
Sadaf Khoomortezaei, Hossein Abdizadeh, Mohammad Reza Golobostanfard
Summary: Recent research has shown that utilizing a WO3/BiFeO3 n-p heterojunction device for photo-electrochemical water splitting can achieve excellent performance, largely due to the built-in potential at the heterojunction interface and the ferroelectric-assisted photocatalytic behavior of BiFeO3.
Article
Materials Science, Ceramics
Thi Kim Thoa Huynh, Youngjae Lee, Shankara S. Kalanur, Hyungtak Seo
Summary: The study demonstrated the use of sputtering technique to coat 1-D TiO2 with a SnO2 nanolayer for surface engineering, enhancing solar water splitting activity. The optimized SnO2/TiO2 system exhibited high photocurrent, incident photon to current efficiency, and hydrogen and oxygen production efficiency.
CERAMICS INTERNATIONAL
(2022)
Article
Engineering, Environmental
Yong-Gyu Noh, Young Jae Lee, Jina Kim, Yu Kwon Kim, JungSeub Ha, Shankara S. Kalanur, Hyungtak Seo
Summary: The study proposed a new method for hydrogen production through catalytic methane pyrolysis using a multi-stage bubble column reactor with liquid metal alloy catalysts. The 3-stage bubble column reactor showed higher methane conversion rates compared to the 2-stage reactor at high temperatures. Analysis of the carbon products revealed that similar carbon-based materials can be obtained from both reactors.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Mohit Kumar, Hyungtak Seo
Summary: Hafnium oxide (HfO2) has unique multifunctional properties that make it ideal for applications like ferroelectric memory, transistors, and pyroelectric sensors. A new self-powered, ultrafast infrared pyroelectric sensor based on HfO2 has been developed with high responsivity. This sensor utilizes temporal infrared light illumination to generate pyro-photocurrent and demonstrates controllable suspension and reestablishment of the response, offering a novel concept for photoreadable memory.
ADVANCED MATERIALS
(2022)
Article
Materials Science, Ceramics
Heecheol Shin, Le Thai Duy, Hyungtak Seo
Summary: This paper presents a deposition approach based on ALD and RTA to improve the temperature coefficient of resistance (TCR) of VOX films by aluminum doping. Introducing Al3+ dopants can hinder the thermally activated phase transition of VO2 phases, leading to an improvement in TCR. However, excessive Al doping can have adverse effects on TCR.
CERAMICS INTERNATIONAL
(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
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
Engineering, Environmental
Ji Min Han, Sang Eun Yoon, Ku Hyun Jung, Onyu Bae, Donguk Kim, Unjeong Kim, Hyungtak Seo, Felix Sunjoo Kim, Ki Chul Kim, Jong H. Kim, Bong-Gi Kim
Summary: This study synthesized a new conjugated polymer with efficient doping using both electron acceptor and Lewis acid type dopants, achieving high electrical conductivities. The interaction between the electron-donating atoms in the doped polymer and the dopants influenced the conductive properties and stability.
CHEMICAL ENGINEERING JOURNAL
(2022)
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
Materials Science, Multidisciplinary
Mohit Kumar, Ji-Yong Park, Hyungtak Seo
Summary: This study demonstrates an enhancement in the self-power UV photoresponse of the silver nanowires/TiO2 Schottky photodetector by utilizing the flexoelectric phenomenon. The device shows measurable photocurrent under low-intensity UV illumination by integrating the photovoltaic and flexo-phototronic effects, resulting in improved rise/fall times and remarkable responsivity and detectivity under self-biased conditions. Microscopic evidence of the flexoelectric effect modulated photoresponse is provided by photoconductive atomic force microscopy measurements.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Chemistry, Applied
Shankara S. Kalanur, Hyungtak Seo
Summary: The study proposed a Cs intercalation strategy on the surface of BiVO4 to enhance water splitting efficiency. By regulating oxygen vacancies and improving catalytic reactions, effective separation and transportation of photogenerated charges were achieved, leading to increased photocurrent and H-2, O-2 production efficiency.
JOURNAL OF ENERGY CHEMISTRY
(2022)
Article
Nanoscience & Nanotechnology
Huije Ryu, Dong-Hyun Kim, Junyoung Kwon, Sang Kyu Park, Wanggon Lee, Hyungtak Seo, Kenji Watanabe, Takashi Taniguchi, SunPhil Kim, Arend M. Zande, Jangyup Son, Gwan-Hyoung Lee
Summary: This study presents a novel approach to simultaneously achieve channel passivation and low-resistance contacts in 2D semiconductor devices. By using monolayer fluorinated graphene as a passivation layer and contact buffer layer, the research successfully demonstrates the formation of Ohmic contacts and high carrier mobility.
ADVANCED ELECTRONIC MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Ayushi Tripathi, Bo Eun Seo, Min Joo Kim, Yoonjoo Lee, Soonyong Lee, Sang Eun Yoon, Un Jeong Kim, Young Wan Kwon, Hyungtak Seo, Kyungwon Kwak, Jong H. Kim, Han Young Woo
Summary: Three p-type thermoelectric polymers based on the indacenodithiophene moiety substituted with bis(alkylsulfanyl)methylene side-chains (IDTS) were synthesized and their thermoelectric characteristics were investigated. Compared to donor-acceptor (D-A) type polymers, the donor-donor' (D-D') type polymer PIDTSDTTT exhibited higher electrical conductivity and power factor when doped with AuCl3. The higher conductivity of PIDTSDTTT originated from its higher carrier concentration. Additionally, PIDTSDTTT showed more stable charge carriers and higher doping stability.
ADVANCED ELECTRONIC MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Ranveer Singh, Mohit Kumar, Unjeong Kim, Hyungtak Seo
Summary: In this study, a self-powered and high-performance alternating current photodetector is fabricated by coating plasmonic Au nanoparticles onto MoO3. The photodetector exhibits high detectivity and good responsivity, as well as rapid response time and nanoscale charge transport capability.
ADVANCED ELECTRONIC MATERIALS
(2022)
Article
Engineering, Electrical & Electronic
Mohit Kumar, Hyungtak Seo
Summary: This study presents a solid-state copper oxide-based device capable of adjustable optical transmittance through fine-tuning electric pulses. The device demonstrates nonvolatile multilevel memory and its working mechanism is explained by the change in stoichiometry of copper oxide induced by oxygen vacancy migration. This research offers a new avenue for the development of reconfigurable thin-film optical devices.
ACS APPLIED ELECTRONIC MATERIALS
(2022)
