Article
Chemistry, Applied
Weiyin Wang, Lu Lin, Haifeng Qi, Wenxiu Cao, Zhi Li, Shaohua Chen, Xiaoxuan Zou, Tiehong Chen, Nanfang Tang, Weiyu Song, Aiqin Wang, Wenhao Luo
Summary: A highly efficient Rh@Al2O3@C single-atom catalyst (SAC) was developed for the hydrogenation of m-chloronitrobenzene, achieving excellent catalytic performance and a sustained selectivity of around 98% to m-chloroaniline. This was attributed to the atomic dispersion of metal and enhanced accessibility of acid function sites.
CHINESE JOURNAL OF CATALYSIS
(2021)
Article
Chemistry, Multidisciplinary
Weijie Yang, Xiaoshuo Liu, Xuelu Chen, Yue Cao, Shaoping Cui, Long Jiao, Chongchong Wu, Chuanmin Chen, Dong Fu, Ian D. Gates, Zhengyang Gao, Hai-Long Jiang
Summary: A new single-atom catalyst Fe-1-N-4-C with excellent catalytic activity and sulfur resistance has been developed for the oxidation of NO and Hg-0, showing promising potential for cleaner coal-fired power plant operations.
ADVANCED MATERIALS
(2022)
Article
Chemistry, Physical
Zhiwei Wang, Shaohua Xie, Ying Feng, Peijie Ma, Kun Zheng, Erhong Duan, Yuxi Liu, Hongxing Dai, Jiguang Deng
Summary: Fe2O3 supported single atom Pt catalysts were synthesized via a novel impregnation-pyrolysis method, showing good light-thermal conversion efficiency and high toluene oxidation performance under simulated sunlight irradiation. The role of Vis-IR light in the photothermal catalytic oxidation of toluene was highlighted, and a possible reaction pathway was proposed based on experiments.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2021)
Review
Materials Science, Multidisciplinary
Yifan Hu, Bolin Li, Changlin Yu, Haocheng Fang, Zesheng Li
Summary: A mechanochemical ball milling process can be used to synthesize single atom catalysts (SACs) and large scale nanomaterials. This review systematically summarizes the ball milling strategies for the preparation of SACs, including solvent-assisted ball milling, solvent-free ball milling, and ball milling abrasion-thermal atomization joint strategy. The latest progress and challenges in the heterogeneous catalysis applications of SACs prepared by mechanical ball milling are also summarized.
Article
Chemistry, Physical
Matteo Farnesi Camellone, Filip Dvorak, Mykhailo Vorokhta, Andrii Tovt, Ivan Khalakhan, Viktor Johanek, Tomas Skala, Iva Matolinova, Stefano Fabris, Josef Myslivecek
Summary: Single-atom catalysts are important heterogeneous catalysts. Recent studies show that single-atom sites on the catalyst substrates can significantly affect the distribution of metal nanoparticles. By controlling the atmosphere, researchers can control the size of Pt nanoparticles on ceria-based single-atom catalysts, leading to changes in catalyst activity and stability. The competition between Pt single-atom sites and Pt nanoparticles determines the morphology of Pt nanoparticle population on the ceria surface. In oxidizing atmosphere, Pt single-atom sites bond strongly with Pt atoms and cause nanoparticle shrinkage, while in reducing atmosphere, Pt single-atom sites are emptied and Pt nanoparticles grow. A generic model of Pt redispersion and coarsening on ceria substrates is proposed, providing an atomic-level explanation for various dynamic processes observed in single-atom catalysts.
Review
Chemistry, Multidisciplinary
Ruiyun Guo, Ke Zhang, Shangdong Ji, Yangzi Zheng, Mingshang Jin
Summary: This review highlights the recent progress and applications of metal nonmetal nanocrystals in the field of catalysis, discussing the different types of nonmetal atoms doped into metal nanocrystals and their applications, particularly in electrocatalysis and organic catalysis. The paper also provides insights into the catalysis-driven rational design of metal-nonmetal nanocrystals.
CHINESE CHEMICAL LETTERS
(2021)
Review
Chemistry, Physical
Shuangfei Cai, Wei Zhang, Rong Yang
Summary: The past four years have seen significant progress in single-atom nanozymes (SANs), a new generation of nanozymes used for catalytic biomedical purposes. SANs have advantages over nanoparticle-based enzymes, such as well-defined structures and efficient atomic utilization, which allows for the development of advanced nanozymes. The atomically dispersed active centers in SANs also facilitate precise control of catalytic performance and help understand mechanism. This review introduces the synthesis, surface engineering, characterization techniques of SANs, discusses their enzyme-like properties and strategies to enhance catalytic activities, and presents their biomedical applications. The challenges and opportunities of SANs are also discussed.
Article
Chemistry, Physical
Neha Antil, Ajay Kumar, Naved Akhtar, Rajashree Newar, Wahida Begum, Ashutosh Dwivedi, Kuntal Manna
Summary: The study introduces a highly efficient, chemoselective, and reusable nickel hydride catalyst for hydrogenation of nitro and nitrile compounds under mild conditions. The catalyst, based on aluminum metal-organic frameworks, has broad substrate scope and excellent functional group tolerance, and can be recycled at least 10 times. This work highlights the potential of MOF-based single-site earth-abundant metal catalysts for practical and eco-friendly production of chemical feedstocks and biofuels.
Article
Chemistry, Physical
Geyla C. Dubed Bandomo, Suvendu Sekhar Mondal, Federico Franco, Alberto Bucci, Vlad Martin-Diaconescu, Manuel A. Ortuno, Phebe H. van Langevelde, Alexandr Shafir, Nuria Lopez, Julio Lloret-Fillol
Summary: The study presents a newly devised CO2 reduction catalyst by loading single-atom centers within a bipyridyl-based COF, showing improved catalytic performance. The findings can guide the rational development of isolated single-atom sites and the enhancement of catalytic performance in reticular materials.
Review
Materials Science, Multidisciplinary
Pratibha L. Gai, Edward D. Boyes
Summary: Most heterogeneous catalytic processes occur between combinations of gases, liquids, and solids at elevated temperatures, playing a critical role for society in various fields. Single atoms and small clusters of atoms have been found to act as primary active sites in catalytic reactions. Understanding and directing reactions at the atomic level is crucial for the development of improved materials and processes. Advances in dynamic in situ microscopy allow for direct probing of heterogeneous catalysis at the atomic level in real time, leading to new knowledge and improved process management.
ANNUAL REVIEW OF MATERIALS RESEARCH
(2023)
Article
Chemistry, Physical
Wen Yan, Jingxiang Sun, Tao Hu, Shuanghong Tian, Jinxi Feng, Ya Xiong
Summary: By anchoring single atom Pt on the surface of SiO2 using ionic liquid, it was found that Pt1(0.1 %)/SiO2 exhibited a significant catalytic effect in generating H2O2, with a concentration 25.2 times and 11.6 times higher than those from pure ultrasound and sonocatalytic processes of Ptn(0.1 %)/SiO2, respectively. This enhancement can be attributed to the dual catalytic processes of Pt1, including sono-splitting of H2O to generate center dot OH as the precursor of H2O2 formation, and the combination of O2 and center dot H to selectively generate center dot OOH.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2023)
Article
Chemistry, Physical
Xiaogang Yu, Guomin Li, Shenghui Tao, Bin Wang, Ce Liu, Huanwang Jing, Feng Shi, Xinjiang Cui
Summary: Single atom catalysts (SACs) exhibit unique catalytic performance in heterogeneous reactions due to unsaturated coordination sites and high metal atom dispersion. In this study, a simple wet impregnation method was used to synthesize Fe-Al2O3 catalysts. Fourier transformation infrared spectroscopy (FTIR) revealed that abundant OH groups attached to the support (Al2O3) surface facilitated the formation of isolated Fe single atoms. High-resolution transmission electron microscope (HR-TEM) and extended X-ray absorption fine structure (EXAFS) confirmed the Fe single atom architecture. Fe-Al2O3 (4.5 wt %) showed enhanced stability and activity in the ethane dehydrogenation reaction.
Article
Chemistry, Physical
Hongqiang Jin, Peixin Cui, Changyan Cao, Xiaohu Yu, Runqing Zhao, Ding Ma, Weiguo Song
Summary: Regulating the density of metal single atoms and exploring their interaction can enhance the performance of single-atom catalysts. In this study, copper single-atom catalysts were synthesized and it was found that the catalytic activity is proportional to the density of copper single atoms. Mechanistic studies revealed that the interactions among neighboring single-atom moieties in high-density copper single-atom catalysts alter the electronic structures, leading to improved adsorption and suppressing side reactions. The ultrahigh-density copper single-atom catalyst exhibited significantly higher activity and utilization efficiency compared to previous reports, providing a practical catalyst for phenol production.
Article
Chemistry, Physical
Junhong Fu, Jinhu Dong, Rui Si, Keju Sun, Junying Zhang, Mingrun Li, Nana Yu, Bingsen Zhang, Mark G. Humphrey, Qiang Fu, Jiahui Huang
Summary: A dual single-atom catalyst (DSAC) Ir1Mo1/TiO2 showed much greater catalytic chemoselectivity than comparable single-atom catalysts for the hydrogenation of 4-nitrostyrene. Density functional theory studies revealed that Ir single atoms affect H2 activation while Mo single atoms are responsible for 4-NS adsorption, with synergistic cooperation contributing to the better catalytic performance.
Article
Chemistry, Multidisciplinary
Yang Zhou, Wei Xi, Zixin Xie, Zhixin You, Xunzhu Jiang, Bing Han, Rui Lang, Chuande Wu
Summary: The study demonstrates the fabrication of high loading Pt single-atom catalysts on diatomite by modifying it with CeO2 nanoparticles to increase defect sites on the support. The enhanced metal-support interaction results in above 1 wt.% loading of Pt species with atomic dispersion, showing good performance in the selective hydrogenation of phenylacetylene to styrene.
CHEMISTRY-AN ASIAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Lu Wang, Zhenxing Wang, Huan Li, Daliang Han, Xing Li, Feifei Wang, Jiachen Gao, Chuannan Geng, Zhicheng Zhang, Changjun Cui, Zhe Weng, Chunpeng Yang, Kian Ping Loh, Quan-Hong Yang
Summary: The deposition behavior of Zn metal anodes in aqueous Zn batteries can be regulated using an aminosilane molecular layer, resulting in dendrite-free Zn metal anodes. This is achieved through a capture-diffusion-deposition process of Zn ions, induced by the aminosilane molecular layer, which promotes reversible Zn stripping/plating and leads to smooth and compact Zn electrodeposited layers. The aminosilane-modified Zn anode exhibits high Coulombic efficiency, long lifespan, and high capacity retention in full cells, making it a promising solution for practical Zn batteries and providing insights into interface modification for other metallic anodes at the molecular level.
Article
Chemistry, Multidisciplinary
Kun Zhang, Xing Li, Li Ma, Fangzheng Chen, Zhongxin Chen, Yijia Yuan, Yaohua Zhao, Jinlin Yang, Jia Liu, Keyu Xie, Kian Ping Loh
Summary: To achieve practical application of lithium-sulfur (Li-S) batteries, the focus is on inhibiting uncontrolled Li deposition and preventing polysulfide shuttling. This study presents the design and synthesis of a fluorinated covalent organic framework (4F-COF)-based membrane that offers high permselectivity and extended battery lifespan. By eliminating polysulfide shuttling and dendritic lithium formation, the 4F-COF/PP separator enables stable Li plating/stripping behaviors and demonstrates excellent cycling retention, rate performance, and areal capacity.
Article
Chemistry, Multidisciplinary
Zhi Chen, Mingzi Sun, Haohan Li, Bolong Huang, Kian Ping Loh
Summary: Understanding the polymorph transition and crystal-amorphous phase transition is crucial for exploring the potential of In2Se3 in resistive memory storage. By monitoring the growth of beta-In(2)Se(3 )layer by layer during molecular beam epitaxy (MBE), we observed a cyclic order-disorder transition where the material exhibited a glassy-like metastable subunit cell film with n < 5 sublayers and highly crystalline beta-In2Se3 at n = 5 layers. The alternating behavior between the indium-cluster layer and In-Se solid solution suggests the diffusion, aggregation, and intermixing of In and Se atoms. These dynamic properties contribute to a defect-driven memory resistive behavior different from the ferroelectric switching of alpha-In2Se3.
Article
Chemistry, Multidisciplinary
Chade Lv, Ning Jia, Yumin Qian, Shanpeng Wang, Xuechun Wang, Wei Yu, Chuntai Liu, Hongge Pan, Qiang Zhu, Jianwei Xu, Xutang Tao, Kian Ping Loh, Can Xue, Qingyu Yan
Summary: Metal-free 2D phosphorus-based materials are potentially efficient and stable catalysts for electrochemical nitrogen reduction reaction. A stable phosphorus-based electrocatalyst, silicon phosphide (SiP), is explored and found to have high catalytic activity for NH3 production. Crystalline SiP nanosheets show superior electrocatalytic performance compared to amorphous SiP nanosheets due to their resistance to oxidization. The findings suggest that SiP nanosheets have great potential as electrocatalysts for nitrogen reduction reactions.
Article
Materials Science, Multidisciplinary
Ibrahim Abdelwahab, Benjamin Tilmann, Xiaoxu Zhao, Ivan Verzhbitskiy, Rodrigo Berte, Goki Eda, William L. Wilson, Gustavo Grinblat, Leonardo de S. Menezes, Kian Ping Loh, Stefan A. Maier
Summary: Parametric infrared upconversion is a nonlinear optical process that converts low-frequency IR photons into high-frequency ultraviolet/visible photons. It is of great importance for various applications, such as security, material science, and healthcare. However, the upconversion efficiency for nanometer-scale materials is typically very low due to limited depth of excitation fields.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Jiteng Gu, Yan Liu, Nannan Meng, Vicknesh Sahmuganathan, Sze Chieh Tan, John Sudijono, Jiecong Tang, Eswaranand Venkatasubramanian, Abhijit Mallick, Febiana Tjiptoharson, Soroosh Daqiqeh Rezaei, Siew Lang Teo, Qiang Zhu, Yunjie Chen, Ming Lin, Zhaogang Dong, Kian Ping Loh
Summary: A dielectric metasurface-based structural color constructed on nanocrystalline diamond film is demonstrated, showing excellent color performance with high brightness and a relatively wide gamut. This work presents the first evidence that nanocrystalline diamond can serve as a robust and highly tunable dielectric platform for information encryption.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Chemistry, Physical
Xiao Wu, Xiangyu Zhang, Wei Yu, Yongxiang Zhou, Walter Wong, Weixin He, Kian Ping Loh, Xiao-Fang Jiang, Qing-Hua Xu
Summary: The all-inorganic layered halide perovskite CsPb2Br5 shows potential applications due to its optical properties and stability, but the mechanism of its photoluminescence remains controversial. The optical properties of CsPb2Br5 depend on sample quality and preparation method. High-quality single crystals of CsPb2Br5 were prepared using a crystallization method, and they showed a conversion into efficient green emitters with a significant enhancement in emission intensity through thermal annealing or irradiation. A mechanism involving thermally induced indirect-to-direct bandgap transition associated with defect formation was proposed based on comprehensive characterization studies and theoretical calculations.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Editorial Material
Materials Science, Multidisciplinary
Kian Ping Loh
SCIENCE CHINA-MATERIALS
(2023)
Review
Chemistry, Multidisciplinary
Jiayang Wu, Han Lin, David J. Moss, Kian Ping Loh, Baohua Jia
Summary: Graphene oxide (GO) was initially developed as a graphene mimic, but has since been recognized as a functional material with its own unique properties. Research on GO in the past decade has greatly advanced material synthesis and property tailoring, leading to rapid progress in GO-based photonics, electronics, and optoelectronics. This review provides an overview of the optical, electrical, and optoelectronic properties of GO and reduced GO, as well as their applications in key technologies such as solar energy harvesting, energy storage, medical diagnosis, image display, and optical communications. The challenges and exciting opportunities for future technological advances in this field are also discussed.
NATURE REVIEWS CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Chaofei Liu, Xiuying Zhang, Xinyun Wang, Ziying Wang, Ibrahim Abdelwahab, Ivan Verzhbitskiy, Yan Shao, Goki Eda, Wanxin Sun, Lei Shen, Kian Ping Loh
Summary: A systematic study of the ferroelectric properties in 2D materials NbOX2 (X = Cl, I) reveals that NbOCl2 exhibits stronger ferroelectricity than NbOI2. The presence of 1D collinear ferroelectric strips is observed in NbOCl2. Scanning tunneling microscopy (STM) imaging provides insights into the unreconstructed atomic structures of NbOX2 surfaces, while scanning tunneling spectroscopy probes the electronic states induced at defect (vacancy) sites.
Review
Chemistry, Multidisciplinary
Clement Kok Yong Tan, Wei Fu, Kian Ping Loh
Summary: Two-dimensional indium(III) selenide (In2Se3) with rich polymorphism shows potential in overcoming depolarization effects in traditional ferroelectrics. α-In2Se3 has attracted attention as a ferroelectric semiconductor at the monolayer level, making it suitable for high-density memory switching modes. However, difficulties in phase identification due to mixing with β-In2Se3 hinder α-In2Se3 studies. Understanding polymorph transitions and crystal-amorphous phase transitions in β-In2Se3 is important for its application in resistive memory storage. This review discusses the differentiation of In2Se3 polymorphs and polytypes and highlights recent applications in ferroelectrics and memory devices.
Article
Physics, Multidisciplinary
Zishen Wang, Chuan Chen, Jinchao Mo, Jun Zhou, Kian Ping Loh, Yuan Ping Feng
Summary: This study proposes an ab initio method to accurately describe Fermi surface nesting and electron-phonon coupling (EPC), and systematically investigates their roles in the formation of charge density wave (CDW). The results show that momentum-dependent EPC leads to softening of phonon frequencies, which become imaginary (phonon instabilities) at CDW vectors. Moreover, including EPC in the mean-field model is necessary to correctly predict the distribution of electron instabilities and CDW gap opening. These findings highlight the crucial role of EPC in CDW formation. The analytical approach used in this study is applicable to other CDW systems.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Jiachao Zhou, Anzhe Chen, Yishu Zhang, Dong Pu, Baoshi Qiao, Jiayang Hu, Hanxi Li, Shuai Zhong, Rong Zhao, Fei Xue, Yang Xu, Kian Ping Loh, Hua Wang, Bin Yu
Summary: This study investigates polarization switching and ionic conduction in 2D vdW CIPS and discovers that the conducting mechanisms can be divided into four states. It demonstrates that dynamically-tunable synaptic responsive behavior can be achieved through controlling the working-state transition.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Physical
Walter P. D. Wong, Xinyun Wang, Rongrong Zhang, Kian Ping Loh
Summary: Hybrid organic-inorganic perovskites (HOIPs) have diverse functionalities such as chirality, ferroelectricity, and photovoltaics. This study focuses on a new family of layered HOIPs called diammonium-halide-diammonium (DHD) perovskites, which have an organic 'spacer' layer. The synthesis of lead-free double perovskite systems using DHD perovskites is also presented, with a discussion on the chemical and structural design considerations.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Chemistry, Multidisciplinary
Zhongxin Chen, Jia Liu, Kian Ping Loh
Summary: The article introduces the application of single-atom catalysts in the flow synthesis of fine chemicals. The researchers discuss the reaction mechanism of SAC-catalyzed processes and the advantages of SACs in drug preparation. They also emphasize the importance of continuous-flow techniques in improving productivity and simplifying process transfer. Additionally, the article identifies technical barriers in SAC research and offers perspectives on standardized and scalable protocols for mass production.
ACCOUNTS OF MATERIALS RESEARCH
(2023)
