Article
Energy & Fuels
Si-Ming Wu, Patrik Schmuki
Summary: This article focuses on the use of TiO2 as a light-absorbing semiconductor for photocatalytic solar energy conversion and various photocatalytic reactions. Different strategies are discussed to improve the photoresponse of TiO2-based materials, including bandgap engineering, surface sensitization, nanostructuring, and geometry optimization. The article provides a comprehensive overview of the effects of fluorine on TiO2, including morphology modifications, and the influence of surface or bulk fluorine on the photocatalytic performance of TiO2. The challenges and future prospects for the development of fluorine effects are highlighted.
Article
Chemistry, Physical
Sang Yeon Lee, Il -Han Yoo, Ranveer Singh, Young Jae Lee, Shankara S. Kalanur, Hyungtak Seo
Summary: Band structure engineering is employed to enhance photocatalytic properties of TiO2 for H-2 production and dye degradation reactions through fluorine doping, resulting in high energy carriers. Nanoscale imaging reveals insights into the enhanced photocatalytic activity of doped TiO2, particularly in the presence of Ti-F bonding in the sequential doped Pd loaded TiO2 nanorod.
APPLIED SURFACE SCIENCE
(2021)
Article
Chemistry, Physical
Suyoung Jang, Vijay C. Karade, Jun Sung Jang, Eunae Jo, Hongjae Shim, Su Gil Kim, Komal Patil, Kuldeep Singh Gour, Jin Hyeok Kim
Summary: This study investigates the optical, electrical, and structural properties of ZnO thin films co-doped with metal atoms and fluorine. The results show that F-doped thin films exhibit improved optoelectronic and structural properties compared to undoped thin films. The co-doped thin films demonstrate a surface passivation effect, leading to decreased resistivity and increased transmittance. When applied to CZTSSe thin-film solar cells, the co-doped thin films contribute to increased power conversion efficiency.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Gouranga Maharana, Reddivari Muniramaiah, J. Yuvashree, Diptendu Mandal, Supravat Mondal, M. Kovendhan, Jean Maria Fernandes, Gangalakurti Laxminarayana, D. Paul Joseph
Summary: This research utilized a co-doping strategy to modify the optoelectronic parameters of SnO2 thin films, and confirmed the success of doping and its effects through various analysis techniques.
SURFACES AND INTERFACES
(2023)
Article
Chemistry, Inorganic & Nuclear
Abdelaziz Abboudi, Sabrina Iaiche, Abdelkader Djelloul, Abdelouahed Chala, Fouzi Kezzoula, Faycal Bensouici, Mohamed Bououdina, Muhammad Humayun
Summary: Bare titanium oxide (TiO2) and fluorine (F) doped TiO2 thin films were successfully fabricated on soda lime glass substrates using the sol-gel dip-coating technique. The influence of hydrofluoric acid (HF) concentration on the structural, optical, and photocatalytic properties of the films was investigated. Characterization techniques such as X-ray diffraction, scanning electron microscopy, X-ray photo-electron spectroscopy, energy dispersive X-ray spectroscopy, atomic force microscopy, and UV-visible spectrophotometry were employed. The results showed the presence of highly crystalline anatase phase TiO2, cracked surfaces in the SEM images, and a decrease in roughness with increasing HF concentration in the AFM images.
INORGANIC CHEMISTRY COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Sichen Jiao, Yujian Sun, Junyang Wang, Dekai Shi, Yapei Li, Xiangkang Jiang, Fangwei Wang, Yuanpeng Zhang, Jue Liu, Xuelong Wang, Xiqian Yu, Hong Li, Liquan Chen, Xuejie Huang
Summary: This study experimentally unravels the multiscale mechanism of fluorination-induced performance improvement in DRX materials and highlights the necessity of adopting an advanced RMC fitting method to obtain a full view of the complex structural features in developing high-capacity DRX cathodes.
ADVANCED ENERGY MATERIALS
(2023)
Article
Chemistry, Physical
Guangxin Song, Rui Gao, Zhao Zhao, Yujun Zhang, Huaqiao Tan, Haibo Li, Dandan Wang, Zaicheng Sun, Ming Feng
Summary: By incorporating Fe as a dopant in TiO2 nanoparticles, oxygen vacancies and dopant energy levels can be generated, promoting the adsorption and activation of N2 molecules. Surface modification with F induces Fe (III) in a high spin state and upshifts the dopant energy level, facilitating Fe 3d electrons backdonation to N 1ag* orbital to promote N2 molecule activation and reduce the limiting potential of NRR. The F-Fe: TiO2 electrocatalyst achieved the highest Faradaic efficiency and maximum NH3 production rate, providing insights into designing catalyst surface electronic states for efficient N2 to NH3 conversion.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2022)
Article
Chemistry, Physical
Zhencui Wang, Jianhang Hai, Jin-Ming Wu, Hisayoshi Kobayashi, Tulai Sun, Zhe Zhang, Chao Geng, Zhenyu Zhang, Wei Wen
Summary: Surface fluorine modification can greatly improve the capacitance of anatase TiO2 up to 6.4 times, providing a new avenue for the design of high-performance electrode materials for electrochemical energy storage and other surface-diffusion-related fields.
APPLIED SURFACE SCIENCE
(2023)
Article
Nanoscience & Nanotechnology
Pei Cui, Panpan Zhang, Xueli Chen, Xiuli Chen, Tao Wan, Yu Zhou, Mingru Su, Yunjian Liu, Haolan Xu, Dewei Chu
Summary: TiNb2O7 has shown great potential as an anode material for lithium-ion batteries due to its high specific capacity and safety. However, its poor ion and electron conductivity have limited its further development. In this study, we successfully improved the ion and electron transport of TiNb2O7 by doping with chlorine and creating oxygen vacancies. These modifications regulated the energy band and crystal structure, leading to enhanced lithium-ion transport behavior and superior rate performance.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Review
Energy & Fuels
Ashraf Uddin, Haimang Yi
Summary: This review discusses the recent progress and challenges in different SnO2 ETL deposition techniques and the performance of PSC devices. It also mentions additional modifications on SnO2 that can eliminate intrinsic defects in the film. Overall, this article is of great importance for comprehending the relationship between the property of SnO2 and its ETL structure and enhancing PSCs' performance.
Article
Chemistry, Multidisciplinary
Zilong Wang, Yuhao Wang, Longyun Shen, Zhaoqing Jin, Ho Mei Law, Anbang Wang, Weikun Wang, Francesco Ciucci
Summary: By using a new nitrate-based additive TEGDN, the incompatibility between poly-DOL and LiNO3 has been successfully resolved, leading to the development of in situ polymerized quasi-solid-state lithium-metal batteries. The resulting electrolyte exhibits high ionic conductivity and oxidation stability, demonstrating excellent cycling performance and capacity retention in experimental tests.
ENERGY & ENVIRONMENTAL SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Snejana Bakardjieva, Filip Mamon, Zdenek Pinc, Radek Fajgar, Ivo Jakubec, Natalija Murafa, Eva Koci, Tatjana Brovdyova, Adriana Lancok, Stefan Michna, Rositsa Nikolova
Summary: This study focuses on Cu-modified 1DTiO(2) microrods (MRs) and their surface properties, investigating the microstructure evolution during annealing and the impact of electronically active Cu species on the bandgap of TiO2. UV absorption properties and photocatalytic hydrogen evolution efficiency were further tested to evaluate the photocatalytic activity of the Cu-doped 1DTiO(2) MRs.
Article
Environmental Sciences
Almudena Aguinaco, Beatriz Amaya, Milagrosa Ramirez-del-Solar
Summary: Fe3+-TiO2 thin films were successfully prepared using a sandwich approach, and their structural, morphological, optical, and photocatalytic properties were studied. The incorporation of Fe3+ altered the material properties to enhance photocatalytic activity.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Chemistry, Multidisciplinary
Zhi Wang, Xinming Zhuang, Binghao Wang, Wei Huang, Tobin J. Marks, Antonio Facchetti
Summary: This study investigates the correlation between polymer structure and charge transport in solution-processed indium oxide: polymer blend flexible thin film transistors. By introducing amino-polymers, it is possible to enhance electron doping capacity and carrier mobility, thereby improving the performance of TFTs.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Green & Sustainable Science & Technology
Z. Zhang, X. Liu, Y. Hu, X. Zhou
Summary: Based on density functional theory, the adsorption processes of fluorine-containing gases on different surfaces were investigated. Co and Pd doping greatly improved the adsorption properties of adsorbents for F2 and SOF2 gas molecules. New chemical bond formation occurred during the adsorption process, leading to different adsorption behaviors.
MATERIALS TODAY SUSTAINABILITY
(2023)
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)
Review
Chemistry, Multidisciplinary
Quansong Zhu, Catherine J. Murphy, L. Robert Baker
Summary: This perspective summarizes recent advances and opportunities using surface ligands to enhance the performance of nanocatalysts for electrochemical CO2 reduction. Several mechanisms are discussed, including selective permeability, modulating interfacial solvation structure and electric fields, chemical activation, and templating active site selection.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Review
Chemistry, Multidisciplinary
Somnath Biswas, L. Robert Baker
Summary: Extreme ultraviolet reflection-absorption (XUV-RA) spectroscopy is a powerful method for studying ultrafast electron dynamics at surfaces. It provides a chemical fingerprint of materials and allows for sensitive detection of oxidation state, spin state, carrier polarity, and coordination geometry. The surface sensitivity of XUV-RA spectroscopy offers new insight into electronic and structural dynamics at surfaces and interfaces.
ACCOUNTS OF CHEMICAL RESEARCH
(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
Chemistry, Physical
Emily Hruska, Jakub Husek, Savini Bandaranayake, L. Robert Baker
Summary: The photophysics of oxygen vacancy-doped anatase TiO2 were investigated using extreme ultraviolet reflection-absorption spectroscopy, revealing the presence of large and small polaron states that can be independently resolved through ultrafast electron and hole dynamics.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Savini Bandaranayake, Ananya Patnaik, Emily Hruska, Quansong Zhu, Alexander Yu. Sokolov, L. Robert Baker
Summary: CuO is commonly used as a photocathode for H-2 evolution and CO2 reduction, but its efficiency is still far below the theoretical limit. To address this, a clear understanding of CuO's electronic structure is necessary, but there is no consensus on the orbital character of the photoexcited electron. This study uses femtosecond XANES spectra to track the element-specific dynamics of electrons and holes in CuO, and reveals the charge transfer state and mixing of conduction band states, providing valuable insight for theoretical modeling of electronic structures.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Gang-Hua Deng, Quansong Zhu, Jaclyn Rebstock, Tomaz Neves-Garcia, L. Robert Baker
Summary: The electrochemical conversion of CO2 has the potential to reduce CO2 emissions and store chemical energy, but the competition between CO2 reduction (CO2R) and the H-2 evolution reaction (HER) hinders its efficient conversion in aqueous solution. This study employs vibrational sum frequency generation (VSFG) spectroscopy to directly probe the interfacial species produced during competing HER/CO2R on Au electrodes, and distinguishes between HER mechanisms based on water reduction and HCO3- reduction.
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)
