Article
Environmental Sciences
Muhammad Saqib Khan, Nadia Riaz, Ahson Jabbar Shaikh, Jehanzeb Ali Shah, Jamshaid Hussain, Muhammad Irshad, M. Saifullah Awan, Asad Syed, Jean Kallerhoff, Muhammad Arshad, Muhammad Bilal
Summary: This study reported the synthesis of graphene quantum dots and iron co-doped TiO2 photocatalysts via modified sol gel method, and investigated their photocatalytic properties. The results showed that GQD-0.1Fe-TiO2-300 exhibited enhanced physicochemical properties and efficient decolorization of RB5 dye. Additionally, GQD-0.1Fe-TiO2-300 maintained stable photocatalytic activity for up to four cycles.
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
(2021)
Article
Chemistry, Physical
Bing Lu, Lingxiao Lv, Xinqun Zhang, Yang Zhao, Qing Chen, Huhu Cheng, Liangti Qu
Summary: Defective carbon materials, especially graphene, have shown great potential in energy conversion and storage due to their unique properties. Traditional preparation methods are destructive and tedious, while a new high-temperature hydrothermal method presented in this work allows for the synthesis of high defect density graphene materials with superior electrocatalytic activity and high capacitance.
JOURNAL OF POWER SOURCES
(2021)
Article
Nanoscience & Nanotechnology
Indranee Hazarika, Tapash Kalita, Poonam Deka, Sonit Kumar Gogoi, Khaled Althubeiti, Ranjit Thakuria, Bedanta Gogoi
Summary: A conjugated system was synthesized using reduced graphene quantum dot (rGQD) and hemin for the selective detection of favipiravir, with a 9-fold increase in fluorescence intensity at 15.6 nM of Fav. The fluorescence enhancement is governed by aggregation-induced emission, and the fluorescence turn-on was observed in human blood plasma and artificial urine as well.
ACS APPLIED NANO MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Sat Septian Dwitya, Yi-Huang Hsueh, Steven S. -S. Wang, Kuen-Song Lin
Summary: This research investigated the synthesis and antibacterial activity of GQDs and N-doped GQDs. The GQDs were prepared by pyrolysis method and considered as a green approach for QD synthesis. N-doped GQDs were synthesized via hydrothermal method with different ratios of urea. The results showed that N-doped GQDs exhibited a lower minimum inhibitory concentration, with N2 and N3 showing the strongest antibacterial effects.
MATERIALS CHEMISTRY AND PHYSICS
(2023)
Article
Nanoscience & Nanotechnology
Avinash Kumar Singh, Smriti Sri, Lakshmi B. V. S. Garimella, Tarun Kumar Dhiman, Sobhan Sen, Pratima R. Solanki
Summary: This study explores an optical sensing platform for the detection of the important mycotoxin AFB1 in the absence of a bioactive environment. The sensor utilizes a fluorescence-based technique that combines graphene quantum dots (GQDs) and AFB1, where AFB1 acts as the quencher of GQD fluorescence. The sensor demonstrates high selectivity and robustness in complex sample matrices, and has a detection limit of 0.158 ng mL(-1). This innovative sensor represents the first GQD-based optical sensor for AFB1.
ACS APPLIED BIO MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Bingjie Hu, Kai Huang, Bijun Tang, Zhendong Lei, Zeming Wang, Huazhang Guo, Cheng Lian, Zheng Liu, Liang Wang
Summary: The performance of semiconducting 2H-phase molybdenum disulfide (2H-MoS2) in the hydrogen evolution reaction (HER) is a significant challenge. This study utilizes theoretical calculations to predict functionalized graphene quantum dots (GQDs) that can enhance the HER activity of bulk MoS2. By modulating the concentration of electron withdrawing/donating functional groups, a functionalized GQD-induced in-situ bottom-up strategy is designed to fabricate near atom-layer 2H-MoS2 nanosheets mediated with GQDs (ALQD). The introduction of functionalized GQDs during the synthesis of ALQD plays a crucial role in improving the HER performance.
NANO-MICRO LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Quang Nhat Dang Lung, Rafael Jumar Chu, Yeonhwa Kim, Tsimafei Laryn, May Angelu Madarang, Oleksiy Kovalchuk, Yong-Won Song, In-Ho Lee, Changsoon Choi, Won Jun Choi, Daehwan Jung
Summary: High quantum efficiency nanoscale devices face challenges due to carrier loss at the surface. Low dimensional materials like 0D quantum dots and 2D materials have been studied to reduce the loss. In this study, we demonstrate a significant enhancement in photoluminescence from graphene/III-V quantum dot mixed-dimensional heterostructures. The distance between graphene and quantum dots in the hybrid structure determines the degree of radiative carrier recombination enhancement. Time-resolved photoluminescence decay also shows increased carrier lifetimes with decreased distance. The proposed optical enhancement mechanism involves energy band bending and hole carrier transfer, which rebalance the carrier densities in quantum dots. This 2D graphene/0D quantum dot heterostructure shows promise for high performance nanoscale optoelectronic devices.
Article
Nanoscience & Nanotechnology
Jung Ho Bae, Suhyeon Kim, Junhyuk Ahn, Chanho Shin, Byung Ku Jung, Yong Min Lee, Yun Kun Hong, Woosik Kim, Don Hyung Ha, Tse Nga Ng, Jiwan Kim, Soong Ju Oh
Summary: The integration of quantum dots into device arrays for high resolution display and imaging sensor systems is challenging due to issues with the patterning process. This study introduces a novel strategy using bifunctional ligands to treat quantum dots for acid-base reaction-assisted photolithography, successfully achieving precise patterning.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Physical
Wencan Hu, Kailong He, Siman Wu, Tianran Chen, Xiaoyuan Yu, Yeru Liang, Mingtao Zheng, Yong Xiao, Hanwu Dong, Yingliang Liu, Hang Hu
Summary: In this study, a novel ordered sandwich-structured nanocomposite consisting of Fe3O4, silicon quantum dots (Si-QDs), and reduced graphene oxide (rGO) is synthesized. Si-QDs play a vital role in guiding the uniform formation and distribution of nano-sized Fe3O4 on rGO nanosheets. The resulting Si-QDs/Fe3O4/rGO composite exhibits high specific capacity, excellent cycling stability, and rate capability. This work provides insights into the effect of Si-QDs on the morphology, structure, and electrochemical performances of the composite.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Jisoo Kim, Jeongah Lim, Ji Dang Kim, Myong Yong Choi, Sunwoo Lee, Hyun Chul Choi
Summary: Pd-graphene quantum dot (Pd-GQD) catalysts were prepared and characterized for their properties and catalytic activity. The study found that Pd-GQD catalyst exhibited higher catalytic activity in the Heck and decarboxylative cross-coupling reactions, and GQD was an effective support material for preparing new catalysts.
Article
Nanoscience & Nanotechnology
Chiashain Chuang, Masahiro Matsunaga, Tian-Hsin Wang, Prathik Roy, Rini Ravindranath, Meenakshi Ananthula, Nobuyuki Aoki
Summary: Magnetic force microscopy was used to study the magnetic properties of nanostructured graphene quantum dot clusters derived from plant leaves. The results showed that the magnetic response of the clusters depended on their height and width, with no observable magnetic signal in individual GQDs or smaller clusters. However, magnetic signals could be effectively detected in plane-distributed GQDCs at room temperature, suggesting potential applications in graphene-based magnetic storage media and spin manipulation quantum devices.
Article
Chemistry, Physical
Tae Hong Im, Chul Hee Lee, Jong Chan Kim, Shinho Kim, Mina Kim, Cheol Min Park, Han Eol Lee, Jung Hwan Park, Min Seok Jang, Doh C. Lee, Sung-Yool Choi, Hee Seung Wang, Hu Young Jeong, Duk Young Jeon, Keon Jae Lee
Summary: In this study, the first metastable phase Ag, ZnS: alpha-In2S3 QDs were synthesized using ultrafast light-material interaction, with the synthesis mechanism experimentally proven and optoelectronic performance evaluated. The study also demonstrated the long-term stability of the synthesized QDs.
Article
Quantum Science & Technology
Si-Si Gu, Bao-Chuan Wang, Ming-Bo Chen, Ting Lin, Yuan Kang, Hai-Ou Li, Gang Cao, Guo-Ping Guo
Summary: The integration of quantum dots with a microwave resonator in the hybrid circuit quantum electrodynamics architecture has created a controllable artificial system and enriched physics through electron-photon interaction. The study investigates a hybrid device where a triple quantum dot is dipole coupled with the electric field of a superconducting quantum interference device array resonator. The results suggest that the hybrid system has the potential to investigate exotic many-body effects and matter-light interaction, depending on the relationship between various Coulomb energy in the quantum dot and the cavity photon energy.
ADVANCED QUANTUM TECHNOLOGIES
(2022)
Article
Chemistry, Physical
Diptiman Dinda, Hyunho Park, Soo Young Park
Summary: By combining N/S hetero atom doping in GQD structure and molecular structural elaboration of organic dye, the study successfully addressed the stability issue of metal-free photocatalysts and achieved sustained HER activity over two days. The N,S-co doping and efficient photoinduced electron transfer to GQD core facilitated by phenazine dye were key factors in improving catalytic efficiency and photostability.
JOURNAL OF CATALYSIS
(2021)
Article
Engineering, Chemical
Nattha Buatong, Chesta Ruttanapun, Chaval Sriwong
Summary: In this study, hydrothermal reduction of graphene oxide sheets was conducted at different temperatures, and the effect of reduction temperature on the structure, morphology, luminescence, and magnetic behavior of reduced graphene oxide quantum dots (rGO-QD) was investigated. It was found that increasing the temperature resulted in enhanced crystallinity, smaller particle size, increased fluorescence intensity, and decreased magnetism of rGO-QDs. Furthermore, it was observed that rGO-QDs prepared at 180 degrees C exhibited non-magnetic properties.
JOURNAL OF THE TAIWAN INSTITUTE OF CHEMICAL ENGINEERS
(2023)
Article
Environmental Sciences
Martin Adrian, Puji Lestari, Ferry Iskandar, Muhammad Miftahul Munir
Summary: The COVID-19 outbreak has impacted people's lives worldwide, and lockdowns have been implemented as a way to control the virus spread. In Indonesia, the government chose to implement public activity restrictions instead of a complete lockdown. Understanding the effect of lockdowns or similar policies on air pollution is valuable for future pandemic control measures and assessing its impact on air quality. A mobile monitoring study was conducted in the urban area of Bandung, Indonesia in July 2021 to examine the correlation between public activity restrictions and air pollution. The study found that public activity restrictions had an impact on air pollution, with a decrease of 20% to 30% in three out of six sub-districts. Mobile monitoring provided a useful visualization of PM2.5 concentration levels on the road, enabling the identification of polluted areas. These findings can provide important insights for government and policymakers in developing future policies to control air pollution and improve public health.
AEROSOL AND AIR QUALITY RESEARCH
(2023)
Article
Energy & Fuels
Jotti Karunawan, Putri Nadia Suryadi, Lauqhi Mahfudh, Sigit Puji Santosa, Afriyanti Sumboja, Ferry Iskandar
Summary: The solid-state method has been used to synthesize LNMO cathode materials with a regular truncated octahedral shape, which exhibits high specific capacity, long-term stability, and high-rate performance.
Article
Chemistry, Physical
Tue Tri Nguyen, Youhei Toyoda, Nur Syakirah Nabilah Saipul Bahri, Annie M. Rahmatika, Kiet Le Anh Cao, Tomoyuki Hirano, Katsuo Takahashi, Yohsuke Goi, Yuko Morita, Mai Watanabe, Takashi Ogi
Summary: In this study, Carbodilite was used as a cross-linker to improve the water resistance of TOCN particles. The presence of polycarbodiimide significantly increased the water resistance of cross-linked TOCN particles.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
Ea Cahya Septia Mahen, Auliya Rahmatul Ummah, Fitri Aulia Permatasari, Akfiny Hasdi Suprijadi, Akfiny Hasdi Aimon, Ferry Iskandar
Summary: This study focuses on the optimized design of blue and green emissive MAPbBr3 perovskite nanostructures (PNSs), which were utilized as fluorescent material in a sandwich-design thin film luminescent solar concentrator (SD-TLSC). The fabricated SD-TLSC demonstrates high performance with an optical efficiency of 5.75% and average visible transmission (AVT) of 85.7%, showing a two-fold enhancement compared to the conventional single thin film LSC configuration. The high performance is achieved by efficient solar radiation absorption in the entire wavelength range due to the unique morphology of the SD-TLSC with different PL emission. These groundbreaking results pave the way for the potential practical use of perovskite-based SD-TLSC as solar windows, marking a significant advancement in the field of building-integrated photovoltaic (BIPV).
Article
Chemistry, Physical
Fitri Aulia Permatasari, Reza Umami, Citra Deliana Dewi Sundari, Tirta Rona Mayangsari, Atthar Luqman Ivansyah, Fahdzi Muttaqien, Takashi Ogi, Ferry Iskandar
Summary: Through integrated experimental and computational studies, the influence of pyrrolic-N concentration and position on the absorption of pyrrolic-N-rich carbon dots was comprehensively elucidated. It was found that a mid-site pyrrolic-N is generated after the pyrrolic-N concentration exceeds 10%, while edge-site pyrrolic-N induces a frontier orbital hybridization, reducing bandgap energy. This study sheds light on the design and optimization of pyrrolic-N-rich carbon dots for the first near infrared window responsive materials in biomedical applications.
Article
Energy & Fuels
Yuyun Irmawati, Bagas Prakoso, Falihah Balqis, Rike Indriyati, Rike Yudianti, Ferry Iskandar, Afriyanti Sumboja
Summary: With the increasing demand for renewable energy diversification, the need for highly active and stable electrocatalysts in all pH ranges is emphasized in electrochemical energy generation and storage systems. This review summarizes strategies to enhance the stability and activity of noble-metal-free nitrogen-doped carbon (M-N/C) as pH-universal oxygen reduction reaction (ORR) electrocatalysts. The ORR mechanism and four strategies including engineering pore structure, adding carbon shell wrapping, introducing multiple nonmetal dopants, and dual metallic active sites are discussed. Future perspectives on the further development and potential applications of M-N/C electrocatalysts are also provided.
Article
Chemistry, Multidisciplinary
Phong Hoai Le, Kiet Le Anh Cao, Yasuhiko Kitamoto, Tomoyuki Hirano, Takashi Ogi
Summary: By studying the formation and framework thickness of macroporous three-way catalyst (TWC) particles synthesized using the template-assisted aerosol process, it was found that the template concentration played a crucial role in maintaining the macroporous structure and controlling the framework thickness between the macropores. The increase in template concentration can reduce the framework thickness of the nanoporous material and improve the mass transfer coefficient.
Article
Nanoscience & Nanotechnology
Tue Tri Nguyen, Nur Syakirah Nabilah Saipul Bahri, Annie M. Rahmatika, Kiet Le Anh Cao, Tomoyuki Hirano, Takashi Ogi
Summary: Porous pectin particles have been synthesized as drug carriers using indomethacin as a model drug, with improved specific surface areas compared to nonporous particles. The porous structure shortens the diffusion path and improves the release rate of drug molecules, resulting in a three times faster drug release rate compared to nonporous particles.
ACS APPLIED BIO MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Delyana Ratnasari, Eka Lutfi Septiani, Kiet Le Anh Cao, Tomoyuki Hirano, Nobuhiro Okuda, Hiroyuki Matsumoto, Takashi Ogi
Summary: Submicron-sized FeNi@SiO2 particles with precisely controllable shell thickness were successfully synthesized in this study using a swirler connector-assisted spray pyrolysis system. The thickness of the SiO2 shell can be tuned by adjusting the parameter conditions, and the fabrication method consistently yielded a high coating ratio of more than 94%. The study also investigated the particle formation process and emphasized the importance of controlling the preheater and SiO2 supplied amount.
Article
Materials Science, Multidisciplinary
Kazuo Takimiya, Kirill Bulgarevich, Singo Horiuchi
Summary: In this study, the transport properties of 2,5,8,11-tetrakis(methythio)perylene (MT-perylene) were found to be far inferior to those of 1,3,6,8-tetrakis(methylthio)pyrene (MT-pyrene). The differences can be attributed to the solid-state electronic structures, which depend on both the molecular electronic structure and crystal structure. Therefore, it is crucial to choose molecules that have an appropriate combination of molecular orbitals and solid-state structure for efficient carrier transport.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Chemistry, Inorganic & Nuclear
Muhammad Alief Irham, Oktaviardi Bityasmawan Abdillah, Darul Roni Rodiansyah, Fakhrian Hanif Tejo Baskoro, Haerul Fahmi, Takashi Ogi, Ferry Iskandar
Summary: In this study, a high-performance FeS2 supercapacitor was synthesized by incorporating polyvinylpyrrolidone (PVP) to solve the limitations of FeS2. PVP prevented dendritic expansion and acted as a binding material, while facilitating a one-step synthesis process. The FeS2/PVP nanocomposite exhibited superior electrochemical properties with high specific capacity and energy density.
DALTON TRANSACTIONS
(2023)
Review
Energy & Fuels
Yuyun Irmawati, Bagas Prakoso, Falihah Balqis, Rike Indriyati, Rike Yudianti, Ferry Iskandar, Afriyanti Sumboja
Summary: With the increasing demand for renewable energy diversification, the focus has been on electrocatalysts with high activity and stability in all pH ranges for electrochemical energy generation and storage systems. Noble-metal-free nitrogen-doped carbon (M-N/C) has been explored as a substitute for expensive platinum-based electrocatalysts, but its activity is limited to alkaline electrolytes. This review summarizes strategies to improve the stability and activity of M-N/C as pH-universal electrocatalysts, including engineering pore structure, adding carbon shell wrapping, and introducing multiple nonmetal dopants and dual metallic active sites.
Article
Chemistry, Multidisciplinary
Kirill Bulgarevich, Kazuo Takimiya
Summary: Despite the importance of studying crystal structures in molecular semiconductors for carrier transport properties, there is still a lack of mature control and prediction methods. To address this issue, the researchers developed an in silico crystallization protocol for simulating brickwork crystal structures of methylchalcogenolated polycyclic aromatic hydrocarbons (PAHs). By analyzing experimental crystal structures, particularly inclined brickwork structures, the researchers expanded the simulation protocol to simulate various brickwork-related crystal structures and evaluate the relative favorability of each polymorphic candidate.
MATERIALS HORIZONS
(2023)
Article
Engineering, Chemical
Nur Syakirah Nabilah Saipul Bahri, Tue Tri Nguyen, Tomoyuki Hirano, Kouhei Matsumoto, Mai Watanabe, Yuko Morita, Takashi Ogi
Summary: This study explores the use of oxazoline-containing polymers as cross-linking agents to improve the water stability of TOCN particles while preserving their particle shape. The results demonstrate that the oxazoline-cross-linked TOCN particles have good stability in water and can be used in practical applications.
ADVANCED POWDER TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Kyohei Nakano, Iat Wai Leong, Daisuke Hashizume, Kirill Bulgarevich, Kazuo Takimiya, Yusuke Nishiyama, Toshio Yamazaki, Keisuke Tajima
Summary: This study develops a new synthetic route to synthesize several new BIT derivatives. The properties of these derivatives are investigated experimentally and computationally, revealing rapid tautomerization in solution and solid state. It is also found that one of the derivatives exhibits good charge transport performance in an organic field effect transistor.
