Article
Chemistry, Physical
Felix Carrascoso, Hao Li, Riccardo Frisenda, Andres Castellanos-Gomez
Summary: This research utilizes strain to modify the optical properties of semiconducting transition metal dichalcogenides, with a focus on MoS2, MoSe2, WS2, and WSe2. The study provides detailed technical descriptions for performing uniaxial strain measurements and proposes a calibration method for accurately determining the applied strain. Reflectance spectroscopy is then employed to analyze the strain tunability of electronic properties in single-, bi-, and tri-layer MoS2, MoSe2, WS2, and WSe2, with an assessment of flake-to-flake variability in 15 single-layer MoS2 flakes.
Article
Chemistry, Physical
Yachao Zhang
Summary: This study investigates the structure of water monolayers on MoS2 and their effect on the band edge levels. The results show the formation of cyclic water clusters through a hydrogen-bonding network. With increasing H2O coverage, shifts in band edges and slight decreases in bandgaps are observed. The band alignment relative to water redox potentials is also examined, revealing that polygon clusters can enhance the hydrogen evolution reaction by lifting the conduction band. This effect is explained by the linear dependence of the band edge offset on an interface electric dipole arising from water assemblies.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Biochemistry & Molecular Biology
Muhammad Pervaiz, Muti Ur Rehman, Faisal Ali, Umer Younas, Mika Sillanpaa, Rizwan Kausar, Asma A. Alothman, Mohamed Ouladsmane, Mohammad Abdul Mazid
Summary: Cellulose/MoS2/GO nanocomposite was synthesized using a hydrothermal method. The formation of the nanocomposite was confirmed by UV-visible and FTIR spectroscopy, and its particle size and morphology were characterized. The nanocomposite exhibited promising biomolecule protective and photocatalytic potential, making it suitable for environmental remediation.
BIOINORGANIC CHEMISTRY AND APPLICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Saurav Sachin, Shivani Rani, Puja Kumari, Subhasmita Kar, Soumya Jyoti Ray
Summary: In this study, the structural, mechanical, electronic, and optical properties of a vertically stacked MoS2/MoSe2 heterostructure were investigated using first-principles-based density functional theory calculations. The relative rotation between the monolayers resulted in the formation of beautiful Moire patterns at twist angles of 21.79 degrees and 30 degrees. The heterostructure exhibited low formation energy and high Young's modulus, indicating its thermodynamic and mechanical stability. Moreover, a phase change from direct to indirect band gap semiconductors and modulation of the band gap due to interlayer coupling were observed. The optical sensitivity of the heterostructure was greatly enhanced at a twist angle of 60 degrees in the visible and infrared regions compared to its monolayers. These twist-assisted electronic and optical properties of the heterostructure provide a novel approach for designing 2D stacked nanostructures for next-generation nano- and optoelectronic devices.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2023)
Article
Chemistry, Physical
Jamilur R. Ansari, Neelam Singh, Shadab Anwar, Satyabrata Mohapatra, Anindya Datta
Summary: The hybrid nanostructure of silver nanoparticles on 2D MoS2 nanosheets exhibited enhanced photocatalytic capability for the degradation of organic dye methylene blue under solar energy. The Schottky junction at the interface induced a shift in Fermi level, leading to efficient charge carrier separation and formation of a sink for photo-excited electrons. The degradation of methylene blue was accelerated by the quick electron transfer and generation of oxidative radicals, demonstrating the potential for water purification applications.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2022)
Article
Chemistry, Physical
Saman Karimi Haji Shoreh, Mahdi Ahmadyari-Sharamin, Hamid Ghayour, S. A. Hassanzadeh-Tabrizi, Reza Pournajaf, Morteza Tayebi
Summary: The research indicates that compositing MgFe2O4 and SnO2 can enhance the efficiency of photocatalytic degradation reaction, while adding Ag can increase the degradation mechanism by preventing electron-holes recombination.
SURFACES AND INTERFACES
(2021)
Article
Energy & Fuels
Rahul Sharma, Nihal, Mamta Sharma, J. K. Goswamy
Summary: In this work, WO3 nanopowder was synthesized, and MoS2/WO3 nanocomposite was prepared. The addition of MoS2 in WO3 led to the formation of layered nanostructures and change in morphology. The electrochemical properties of the nanocomposites improved due to the large active surface area. The nanocomposites also exhibited good optical properties at low MoS2 contents.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2022)
Article
Chemistry, Multidisciplinary
Qian Cai, Qiankun Ju, Wenting Hong, Chuanyong Jian, Taikun Wang, Wei Liu
Summary: This study demonstrates a chemical vapor deposition method to control the growth of large scale MoS2/MoSe2 vertical heterostructures on a molten glass substrate using water as the oxidizing agent, ensuring sufficient and uniform delivery of the metal precursor. This offers an efficient approach for developing integrated electronic and optoelectronic devices with other layered heterostructures.
Article
Chemistry, Multidisciplinary
Gerald Lepcha, Rajib Sahu, Santanu Majumdar, Saikat Banerjee, Arpita Bhowmick, Samya Sen, Bholanath Panda, Debasis Dhak, Keka Sarkar, Biswajit Dey
Summary: Different nanostructural composites-capped silver nanoparticles were synthesized using supramolecular hydrogel (SHGel) structures containing two-dimensional metal dichalcogenides (MoS2, MoSe2, and MoS2-MoSe2) as stabilizing agents. The morphological characteristics of the composite-capped Ag-NPs were observed using transmission electron microscopy (TEM) and elemental analysis confirmed the composition of the nanocomposites. X-ray photoelectron spectroscopy was employed to analyze the composite-capped Ag-NPs. The antibacterial activity of the composite-capped Ag-NPs against two bacterial strains and the anticancer activity against a human lung cancer cell line were tested.
NEW JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Abhijeet Kumar, Denis Yagodkin, Nele Stetzuhn, Sviatoslav Kovalchuk, Alexey Melnikov, Peter Elliott, Sangeeta Sharma, Cornelius Gahl, Kirill Bolotin
Summary: The study utilized a TMD heterostructure MoS2-MoSe2 to investigate spin/valley polarization and relaxation mechanisms of photoexcited carriers, revealing that the carriers maintain their spin across the interface and exhibit significantly different depolarization rates for electrons and holes. The findings offer insights into the spin/valley dynamics of photoexcited carriers and establish TMD heterostructures as generators of spin currents in spin/valleytronic devices.
Article
Engineering, Environmental
Zhangqian Liang, Yanjun Xue, Xinyu Wang, Yanli Zhou, Xiaoli Zhang, Hongzhi Cui, Guiqing Cheng, Jian Tian
Summary: The study reveals that Co-doped MoS2 nanosheets can achieve significantly enhanced photocatalytic H-2 production in alkalescent environment, providing insights for the development of low-cost and highly effective photocatalysts.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Archita N. S. Adluri, Brett Henderson, Irina Paci
Summary: Ceramic materials, such as metal oxides and silicates, are widely used in electronic insulators. By introducing metal cluster dopants and molecular-scale inclusions, new high-kappa solid-state dielectrics with tunable field-response properties can be manufactured. This study models the polarization of molecular-scale silver inclusions in a magnesium oxide matrix and investigates the effects of nanoparticle size, shape, and orientation on the dielectric response.
Article
Nanoscience & Nanotechnology
Sweta Rahul, Sweta Sharma, Pooja Devi, Sunil K. Arora
Summary: In this study, a photocathode (PC) was fabricated by spray coating MoSe2 nanosheets on p-SiNWs, and its performance in photoelectrochemical-hydrogen evolution reaction was studied. The p-SiNWs-MoSe2 PC showed significantly higher photocurrent density and lower charge transfer resistance compared to p-SiNWs, attributed to the high donor density of MoSe2 nanosheets. These results provide a scalable and effective route for solar-fuel conversion at a large scale.
Article
Chemistry, Physical
A. Martinez-Jodar, S. Villar-Rodil, M. A. Salvado, D. F. Carrasco, P. Pertierra, J. M. Recio, J. I. Paredes
Summary: Two-dimensional MoSe2 nanosheets were found to have higher activity than MoS2 nanosheets as catalysts for nitroarene reduction in water treatment. Density functional theory (DFT) calculations revealed the reduction pathway on 2D MoSe2 and explained the selectivity displayed by the catalyst. The MoSe2 nanosheets were further coated with colloidal stabilizers and immobilized on polymer foam for practical application, showing no significant loss of activity after multiple catalytic cycles.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2023)
Article
Chemistry, Multidisciplinary
Mikhail Y. Y. Lukianov, Anna A. A. Rubekina, Julia V. V. Bondareva, Andrey V. V. Sybachin, George D. D. Diudbin, Konstantin I. I. Maslakov, Dmitry G. G. Kvashnin, Olga G. G. Klimova-Korsmik, Evgeny A. A. Shirshin, Stanislav A. A. Evlashin
Summary: The extraordinary properties of two-dimensional materials make them attractive for various applications, especially in optics. In this study, the absorption and luminescent properties of MoS2 exfoliated in the presence of sodium cholate were investigated. The use of shear-assisted liquid-phase exfoliation and sodium cholate as a surfactant resulted in the highest quality MoS2 nanosheets. The photoluminescent properties of MoS2 nanosheets showed slight variations with changes in surfactant concentrations. This work is of practical importance for improving the photoluminescent properties of MoS2 through chemical functionalization.
Article
Chemistry, Multidisciplinary
Jinming Wang, Eunhyo Kim, Dharani Praveen Kumar, Akkammagari Putta Rangappa, Yujin Kim, Yuexing Zhang, Tae Kyu Kim
Summary: Dual-atom-site catalysts (DACs) have attracted attention in heterogeneous catalysis, and cobalt-based atom site catalysts with a Co-2-N coordination structure synthesized in this study exhibited superior catalytic performance for CO2 reduction, significantly outperforming cobalt-based single-atom-site catalysts. The excellent CO2 adsorption strength at dimeric Co active sites is the intrinsic reason for the superior activity of CoDACs.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
D. Praveen Kumar, A. Putta Rangappa, Khai H. Do, Yul Hong, Madhusudana Gopannagari, K. Arun Joshi Reddy, P. Bhavani, D. Amaranatha Reddy, Tae Kyu Kim
Summary: This study presents the development of few-layered 2D exfoliated g-C3N4 nanosheets and their combination with inorganic perovskite-based Ba2NbFeO6 nanostructures for solar fuel production, achieving high rates of production. The enhanced activity of the composite material is attributed to the improved surface-active sites of g-C3N4 through exfoliation, the unique properties of BNF nanosheets, and their combination, resulting in the highest efficiency compared to previously reported g-C3N4-based photocatalysts.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Physical
K. Arun Joshi Reddy, D. Amaranatha Reddy, Da Hye Hong, Madhusudana Gopannagari, A. Putta Rangappa, D. Praveen Kumar, Tae Kyu Kim
Summary: The selection of layered number and time-course destruction of layers can enhance the charge transfer between 2D-to-1D heterostructures, leading to improved efficiency of solar-to-hydrogen evolution. Assembling different numbers of 2D-WSe2 nanolayers on CdS nanorods resulted in a drastic improvement in photocatalytic performance, demonstrating the potential of numbered WSe2 nanosheets as a co-catalyst material.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Engineering, Electrical & Electronic
Lianqing Yu, Yankun Wang, Jinhui Wang, Xingyu Zhao, Wei Xing, Liana Alvares Rodrigues, D. Amaranatha Reddy, Yaping Zhang, Haifeng Zhu
Summary: Efficient copper phthalocyanine gas sensors with sensitive and selective analysis capabilities for toxic gases at room temperature have shown great potential in recent years. In this study, a gas sensor based on copper phthalocyanine (CuPc) was prepared using a low-temperature physical vapor deposition (PVD) method. The uniform cotton-wool nanowires film had high yield and easy peel-off properties. The PVD preparation temperature significantly affected the recovery and cyclic properties of the gas sensor for chlorine. The high-performance CuPc nanowires prepared at 230 degrees C had the lowest detection limit and a much faster recovery time compared to previous results. Additionally, it exhibited excellent light-induced gas-sensitive characteristics to Cl-2 at room temperature. This sensor has potential applications in photo-gas sensors, photocatalytic devices, or photoelectric devices.
SENSORS AND ACTUATORS A-PHYSICAL
(2022)
Article
Chemistry, Physical
A. Putta Rangappa, D. Praveen Kumar, Jinming Wang, Khai H. Do, Eunhyo Kim, D. Amaranatha Reddy, Hyun S. Ahn, Tae Kyu Kim
Summary: SnS2 nanosheets with excellent light-driven CO production rate were obtained through a facile hydrothermal method. After modification with Ag2S quantum dots, the nanocomposites exhibited significantly higher CO/CH4 production rate than pristine SnS2. The study provides new opportunities for exploring efficient photocatalytic CO2 reduction systems.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Chemistry, Physical
Madhusudana Gopannagari, D. Amaranatha Reddy, Da Hye Hong, K. Arun Joshi Reddy, D. Praveen Kumar, Hyun S. Ahn, Tae Kyu Kim
Summary: A novel Fe-doped NiOX layer was introduced to the copper vacancy-induced CuBi2O4 photocathode, improving surface conductivity and interface charge transfer. The Fe:NiOX layer acted as an efficient hole-transport layer, enhancing the PEC performance characteristic of the photocathode.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Chemistry, Physical
D. Praveen Kumar, Sumin Seo, A. Putta Rangappa, Seunghee Kim, K. Arun Joshi Reddy, Madhusudana Gopannagari, P. Bhavani, D. Amaranatha Reddy, Tae Kyu Kim
Summary: The use of non-precious and noble-metal free catalysts for water photo conversion into hydrogen is of significant interest, and the doping of a foreign metal into the MoS2 system has been found to be an effective method for enhancing the hydrogen production rate. In this study, CdS nanorods are decorated with zinc-doped MoS2 nanosheets, and the resulting composite shows excellent photocatalytic activity for hydrogen evolution. The loading of Zn-MoS2 enhances the synergistic effects of the photocatalyst and improves the stability of the material. This Zn-MoS2/CdS composite is believed to have great potential as a low-cost, highly-efficient catalyst for the photocatalytic reduction of water.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Nanoscience & Nanotechnology
Hyeong Seop Shim, Minji Ko, Sangwon Nam, Jun Hwan Oh, Seonghyun Jeong, Yoonji Yang, Seung Min Park, Young Rag Do, Jae Kyu Song
Summary: In order to achieve suitable quantum yield and color purity for visible emitters in display devices, the optical features of indium phosphide (InP) quantum dots (QDs) are improved. Two types of InP cores are synthesized using different phosphorus precursors, and then gradient-alloyed inner and outer shells are fabricated to complete the environmentally friendly QDs structure. The quantum yields of the two types of QDs are comparable to state-of-the-art InP QDs, with bandwidths of 35 and 36 nm respectively. The results suggest strategies to enhance the quantum yield and color purity of InP QDs for display device applications.
ACS APPLIED NANO MATERIALS
(2023)
Article
Chemistry, Physical
Pooja Varma, Madhusudana Gopannagari, K. Arun Joshi Reddy, Tae Kyu Kim, D. Amaranatha Reddy
Summary: A low-cost, noble-metal-free photocatalyst with high catalytic reactivity has been successfully developed by utilizing N-doped Fe3C nanocages adorned with ultrathin ZnIn2S4 nanosheets produced from a dual metal organic framework. The highly porous hybrid structure provides a large number of active sites for catalytic reduction events and enables better capture of visible light through light scattering.
Article
Chemistry, Multidisciplinary
Inae Song, Yaeeun Eom, P. Muthu Austeria, Da Hye Hong, Mani Balamurugan, Ramireddy Boppella, Do Hwan Kim, Tae Kyu Kim
Summary: Tuning the coordination environment and geometric structures of single atom catalysts is an effective approach for maximizing catalytic efficiency. A template-based synthesis strategy was proposed in this study to synthesize high-density NiNx sites on the surface of nitrogen-doped carbon nanofibers. The results showed that the dual engineering strategy increased the number of active sites and utilization efficiency of each single atom, resulting in superior catalytic activity and selectivity for CO2 reduction reactions.
Article
Chemistry, Multidisciplinary
Akkammagari Putta Rangappa, Dharani Praveen Kumar, Khai H. H. Do, Jinming Wang, Yuexing Zhang, Tae Kyu Kim
Summary: Constructing stable heterostructures with regularly arranged TiO2 nanodots in covalent organic frameworks (COFs) via pore-wall modification strategy improves active site accessibility and catalytic efficiency. Density functional theory studies reveal that pore-wall modification induces strong interactions between COF and TiO2, resulting in large energy transfer via N-Ti-O bonds. This work demonstrates the feasibility of developing stable COF and metal oxide heterostructures for artificial photosynthesis.
Article
Green & Sustainable Science & Technology
Madhusudana Gopannagari, Kethireddy Arun Joshi Reddy, Song Inae, Hyung Suk Bae, Junho Lee, Tae Gyun Woo, A. Putta Rangappa, Dharani Praveen Kumar, D. Amaranatha Reddy, Tae Kyu Kim
Summary: By incorporating Ag+ ions into the nanosized porous CBO network, the photocathode exhibits improved charge carrier separation and transfer. The introduction of a NiO hole-selective layer further enhances the charge transfer across the back interface. Compared with unmodified CBO, the NiO/ACBO photocathode shows three-fold enhanced photocurrent performance.
ADVANCED SUSTAINABLE SYSTEMS
(2023)
Article
Materials Science, Multidisciplinary
Sangwon Nam, SeungJe Lee, Seonghyun Jeong, Minji Ko, Hyeong Seop Shim, Eunha Hong, Seung Min Park, Young Rag Do, Jae Kyu Song
Summary: The optical features of multiple-layered heterostructures composed of III-nitride semiconductors were studied for tunable nanolasers. The confined optical effects in nanorods lead to polariton lasing with distinct dispersion. The alloyed systems of InGaN and AlGaN enable tunable color lasing in the visible region. Controllable triple-color lasing was demonstrated in the multiple-layered heterostructure for the first time, showcasing the potential for diverse nanophotonic devices.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Chemistry, Physical
Khai H. Do, D. Praveen Kumar, A. Putta Rangappa, Jehee Lee, Sungin Yun, Tae Kyu Kim
Summary: In this study, a 2,2'-bipyridine-based ketoenamine covalent organic framework (TpBpy) was used to promote CO2 photoreduction processes by bridging CdS nanoparticles and a [Co(bpy)(3)](2+) cocatalyst. This system showed strong solar light harvesting ability, high CO2 adsorption capacity, efficient charge carrier transfer, and rapid photoelectron injection. This study provides insights for the development of solar-driven CO2 reduction.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)