Article
Physics, Applied
Yong Han, James W. Evans, Michael C. Tringides
Summary: The study investigates the kinetic process of foreign guest atom intercalation into graphene layers and provides numerical values for the critical energy barriers through theoretical calculations.
APPLIED PHYSICS LETTERS
(2021)
Article
Physics, Applied
Ganying Zeng, Zhenyu Fang, Chengbing Qin, Liantuan Xiao, Suotang Jia
Summary: In this work, we developed a method to tune the lattice distortion of multilayer graphene using H2SO4-intercalation, which leads to the acquisition of noncentrosymmetric electric dipoles and enhances the second-harmonic generation (SHG) response. The SHG change is reversible after deintercalation, as the lattice distortion can be restored. Our research on the intercalating-induced SHG effect may contribute to a better design of graphene-based nonlinear optical devices in the future.
APPLIED PHYSICS LETTERS
(2023)
Article
Chemistry, Physical
Jiaxi Zeng, Xiaoli Zhao, Hongbin Lu
Summary: This study demonstrates a liquid-phase sewing strategy to construct carbon foams (CFs) directly from flake graphite, overcoming the challenge of constructing CFs with desired structures and intact lattice integrity. The CFs constructed through this method exhibit high conductivity and high-performance electromagnetic interference shielding effectiveness.
CHEMISTRY OF MATERIALS
(2022)
Article
Chemistry, Physical
Fanhao Tang, Dongxu He, Hao Jiang, Rongshuo Wang, Zheling Li, Weidong Xue, Rui Zhao
Summary: In this study, a top-down strategy was presented to directly fabricate GO/graphite foam from graphite paper. The synergistic effect with GO and graphite greatly enhanced the electrochemical performance of the electrode.
Article
Chemistry, Physical
Zhi Cai, Haley Weinstein, Indu Aravind, Ruoxi Li, Sizhe Weng, Boxin Zhang, Jonathan L. Habif, Stephen B. Cronin
Summary: In this study, Raman spectra and infrared (IR) imaging were collected to observe the intercalation-deintercalation process in a multilayer graphene device. The intercalation of TFSI- anions into the MLG was observed through the emergence and disappearance of the intercalated G band mode at around 1610 cm(-1). By integrating the Raman signal over hundreds of cycles, significant information can be obtained. The intercalation/deintercalation process was also monitored using thermal imaging based on voltage-induced changes in the carrier density, complex dielectric function & epsilon;(& omega;), and thermal emissivity of the device.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Physical
Lei Wang, Fei Huang, Guoyin Zhu, Zhihui Dai
Summary: A one-step solid-state synthesis method was used to prepare orthogonal Nb2O5 nanocrystals/graphene composites as high-performance anode materials in lithium-ion batteries. The Nb2O5/G material showed excellent electrochemical performance due to its nanoscale crystalline structure and highly conductive graphene substrate. A reversible structural phase transition between orthogonal Nb2O5 and tetragonal Li1-xNbO2 was verified, and the Nb2O5/G||graphite dual-ion batteries exhibited good cyclic performance and rate capability.
Article
Chemistry, Multidisciplinary
Wanzhen Xu, Wenjie Zhu, Junliang Shen, Mingyue Kuai, Yi Zhang, Weihong Huang, Wenming Yang, Mengmeng Li, Sheng Yang
Summary: Graphene oxide (GO) has various applications in energy devices, biomedicine, environmental protection, and composite materials. A stepwise electrochemical method for fast GO preparation is reported, which involves spontaneous persulfate intercalation and anodic electrolytic oxidation. This method avoids uneven intercalation and insufficient oxidation, significantly shortening the overall duration, and resulting in GO with higher oxygen content and enhanced adsorption capacity compared to traditional methods.
Article
Materials Science, Multidisciplinary
Fan Zhang, Peng Yin, Qunfeng Zeng, Jianmei Wang
Summary: This study systematically investigated the influences of high temperature on the tribological properties of PRG sliding against WC-Ni alloy and found that PRG exhibited ultra-low coefficient of friction at high temperature due to the formation of graphite tribofilms.
Article
Chemistry, Physical
Seoin Back, Seung-Ho Yu, Yuanzhe Piao, Juhyung Choi, Aihua Jin, Hyun Dong Jung, Dongjin Ko, Ji Hyun Um, Yoon Choi, So Hee Kim
Summary: This study presents a novel nanoarchitecture of nitrogen and sulfur co-doped graphene nanoribbons, which exhibit high capacity and stable cycling performance as anodes for potassium-ion batteries. Theoretical calculations demonstrate that graphene nanoribbons with NS co-doping have improved potassium-ion intercalation properties compared to parallel-edged nanoribbons.
ENERGY STORAGE MATERIALS
(2022)
Article
Chemistry, Physical
Elena Voloshina, Beate Paulus, Yuriy Dedkov
Summary: The interfaces of graphene with Ru(0001) and Ir(111) were modified using intercalation of a thin Mn layer, leading to the formation of surface alloys between atoms of the guest metal and the substrate. The unique structures formed on both Ru(0001) and Ir(111) interfaces were explained through phase diagram pictures and comparison of calculated total energies.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Chemistry, Physical
Zengtong Jiao, Chi Zhang, Wei Zhang, Linfeng He, Zhenming Lu, Meili Qi, Caixia Li, Suwei Cheng, Gang Xu, Xiaotong Chen, Bing Liu, Yaping Tang
Summary: This study investigated the effect of HNO3 concentration on galvanostatic deconsolidation, revealing that 34% HNO3 was the most effective in separating matrix graphite due to the combined effect of intercalation, hydrolysis, and oxygen evolution.
Article
Chemistry, Physical
James G. McHugh, Pavlos Mouratidis, Kenny Jolley
Summary: This study investigated the behavior of ruthenium nanoclusters on graphene using first-principles calculations. The results demonstrated that intercalated atoms can shear the lattice and form an AA stacking configuration at high density of single Ru atom interstitials, with this effect weakening with increasing cluster size. The interlayer stacking configuration also significantly influenced cluster diffusion.
APPLIED SURFACE SCIENCE
(2023)
Article
Physics, Applied
Chaoping Liang, Feilong Wang, Sai Tang
Summary: In this work, the Li ordering and its influence on Li intercalation and plating on graphite, bilayer, and single-layer graphene are investigated. The results show that Li intercalation has a multistage feature for graphite and bilayer graphene. High concentration of Li atoms results in negative discharge voltage in graphite and bilayer graphene. However, Li atoms uniformly cover the surface of single-layer graphene and form an atomic island at high Li concentration.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Akira Iyo, Hiraku Ogino, Shigeyuki Ishida, Hiroshi Eisaki
Summary: Graphite intercalation compounds (GICs) have various functions and their synthesis can be accelerated by using Na as a catalyst. By mixing alkali metals and graphite powder with Na at room temperature, LiC6n (n=1,2), KC8, KC12n (n=2,3,4), and NaCx can be synthesized. Heating Na-added reagents at 250 degrees C results in the synthesis of A(E)C(6) (A(E)=Ca, Sr, Ba). The Na-catalyzed method enables rapid and mass synthesis of homogeneous GIC samples in a simpler manner than conventional methods.
ADVANCED MATERIALS
(2023)
Article
Crystallography
Gintare Rimkute, Gediminas Niaura, Rasa Pauliukaite, Justina Gaidukevic, Jurgis Barkauskas
Summary: In this study, graphene-polypyrrole nanocomposites were synthesized via a wet-way protocol using a graphite bisulfate precursor. It was discovered that the proposed synthesis method could produce graphene with low defect concentration. The research on anion intercalation involving relatively complex structures, such as HSO4-, is still limited and requires further investigation. This study contributes to the development of cost-effective, scalable, and highly efficient intercalation methods.
Article
Chemistry, Physical
Philipp Rietsch, Mohammad Zeyat, Oskar Huebner, Katrin Hoffmann, Maximilian Kutter, Alice Paskin, Julian Uhlig, Dieter Lentz, Ute Resch-Genger, Siegfried Eigler
Summary: The absorption and emission properties of organic dyes can be tuned by altering the substitution pattern, but adjusting fluorescence lifetimes within a range of several tens of nanoseconds while maintaining spectral features and fluorescence quantum yield is challenging. The substitution-dependent emissive properties of fluoranthene dyes can be utilized for labeling and encoding applications.
JOURNAL OF PHYSICAL CHEMISTRY B
(2021)
Article
Chemistry, Physical
Heng Liu, Guangling He, Xuetao Liu, Yanlin Zhu, Siegfried Eigler, Lei Han
Summary: Nanostructured nitrogen-doped carbon materials with hierarchical porous structure and high specific surface area were synthesized using an ion-induced method, showing comparable oxygen reduction reaction performance and stability with commercial Pt/C. The resulting material exhibited good methanol tolerance and stability, leading to high performance in assembled Zn-air battery.
Article
Chemistry, Physical
Felix Witte, Philipp Rietsch, Shreya Sinha, Alexander Krappe, Jan-O Joswig, Jan P. Goetze, Nithiya Nirmalananthan-Budau, Ute Resch-Genger, Siegfried Eigler, Beate Paulus
Summary: This study investigates the complex aggregation features and photophysical properties of diaminodicyanoquinone derivatives through a combined experimental and theoretical approach. A novel mechanism involving metastable dimeric species to generate nonfluorescent J-aggregates is proposed, shedding light on aggregation-induced optical effects in dye aggregates. These results have broad implications for the photophysics of dye aggregates.
JOURNAL OF PHYSICAL CHEMISTRY B
(2021)
Article
Chemistry, Physical
Yalei Hu, Qing Cao, Christof Neumann, Tibor Lehnert, Felix Boerrnert, Yiqing Wang, Ute Kaiser, Andrey Turchanin, Siegfried Eigler
Summary: A facile and controllable wet-chemical method is presented for producing solution-processible porous graphene derivatives. Pores with tunable diameters between 5 nm and 500 nm can be etched into the basal plane of oxo-G using hydroxyl radicals, resulting in flakes with mu m-size lateral dimensions. The study proposes a plausible mechanism for the growth of these pores based on various spectroscopic techniques.
Article
Chemistry, Multidisciplinary
Yiqing Wang, Christof Neumann, Marleen Hussmann, Qing Cao, Yalei Hu, Oisin Garrity, Patryk Kusch, Andrey Turchanin, Siegfried Eigler
Summary: The wet-chemical generation of pores in graphene poses a challenge due to preexisting lattice defects from synthesis, which hinder controlled pore growth. By using oxo-functionalized graphene with controlled vacancy defects, pores with carbonyl-functionalized rims have been successfully fabricated. The experiments demonstrate that pore size increases with etching time and that heterostructures with intrinsic MoS2 doping can be created.
ADVANCED MATERIALS INTERFACES
(2021)
Article
Chemistry, Physical
Yiqing Wang, Fabian Grote, Qing Cao, Siegfried Eigler
Summary: The study found that introducing oxygen functional groups near defects in graphene can significantly enhance its activity and selectivity in hydrogen peroxide production. After adding oxo-groups near these defect sites, the selectivity of H2O2 increased to over 84%, and the half-wave potential was more positive than initial oxo-functionalized graphene.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Chemistry, Physical
Sergey Trishin, Tobias Mueller, Daniela Rolf, Christian Lotze, Philipp Rietsch, Siegfried Eigler, Bernd Meyer, Katharina J. Franke
Summary: In this study, the behavior of ethyl-diaminodicyanoquinone molecules on a metal surface was investigated using a combination of scanning tunneling microscopy and noncontact atomic force microscopy. The study found that despite being screened by the metal substrate, the molecules still retained a significant dipole moment. Additionally, the adsorption of these molecules led to a decrease in the local contact potential on the metal substrate.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Giacomo Reina, Cristian Gabellini, Maria Maranska, Fabian Grote, Shan Min Chin, Lucas Jacquemin, Francois Berger, Paola Posocco, Siegfried Eigler, Alberto Bianco
Summary: Gene therapy has become a forefront treatment for various diseases. However, the clinical application of graphene oxide as a gene vector is limited due to the lack of homogeneity in different synthetic methods. In this study, a new class of graphene oxide called oxo-G was prepared with controlled size and surface chemistry. After functionalization, oxo-G was able to efficiently complex siRNA and induce gene silencing in vitro at doses more than 20 times lower than previous graphene-based materials. This work aims to inspire further development of oxo-G materials for biomedical applications, with the hope that oxo-G can be considered as an alternative candidate for future in vivo gene silencing.
Article
Chemistry, Physical
Yalei Hu, Christof Neumann, Lena Scholtz, Andrey Turchanin, Ute Resch-Genger, Siegfried Eigler
Summary: Graphene quantum dots with long-wavelength emission were synthesized using a solvothermal method and their chemical structure and optical properties were investigated. The effects of solvent polarity and proticity on the optical properties were studied, and a luminescence mechanism was proposed. Additionally, the potential of graphene quantum dots for optical sensing of trace amounts of water was assessed.
Article
Chemistry, Physical
Steffen M. Brulls, Valentina Cantatore, Pui Lam Tam, Per Malmberg, Elisabet Ahlberg, Itai Panas, Siegfried Eigler, Jerker Martensson
Summary: Functionalization and modulation of graphene's electronic properties using organic polycations were investigated. Wet-chemical non-covalent functionalization was performed on chemical vapor deposition graphene and reduced graphene oxide. The number of anions and the properties of the benzimidazole-based systems were found to play a crucial role in determining the redox properties and bonding to graphene. This study provides insights into the cooperative effects of the system's structure and anions on the binding affinity.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Yiqing Wang, Siegfried Eigler
Summary: The study investigates the effects of thin film coating on electrodes, loading, size of GO flakes, and macroscopic coffee-ring effect during drying. Effective transfer of protons and electrons is crucial for electrochemical reduction of GO.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Zhenping Wang, Qing Cao, Kai Sotthewes, Yalei Hu, Hyeon S. Shin, Siegfried Eigler
Summary: This research focuses on modulating the optoelectronic properties of monolayer MoS2 on different graphene monolayers, showing that oxygen-functionalized graphene and reduced-oxo graphene can significantly enhance the photoluminescence intensity of MoS2, while pristine graphene leads to photoluminescence quenching. Additionally, the increase in photoluminescence intensity is higher in reduced-oxo graphene/MoS2 compared to oxygen-functionalized graphene/MoS2.
Article
Chemistry, Physical
Felix Witte, Philipp Rietsch, Nithiya Nirmalananthan-Budau, Florian Weigert, Jan P. Goetze, Ute Resch-Genger, Siegfried Eigler, Beate Paulus
Summary: The concept of aggregation-induced emission is used to explain the photoluminescence of nonfluorescent excimers in solid-state materials. This study investigates the photophysical properties of certain DADQ derivatives in the solid state through a combination of experimentation and theory, revealing both aggregation-induced emission and aggregation-caused quenching effects. The analysis suggests that multiple emissive species contribute to the photophysical properties of DADQs, with the main emission peak exhibiting broadening and a blue-shifted shoulder.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Review
Chemistry, Multidisciplinary
Bangun Satrio Nugroho, Muh Nur Khoiru Wihadi, Fabian Grote, Siegfried Eigler, Satoru Nakashima
Summary: This paper discusses the potential of graphene oxide and polyoxometalates as radionuclide adsorbents, highlighting their unique properties and adsorption mechanisms, and pointing out future research directions.
INDONESIAN JOURNAL OF CHEMISTRY
(2021)
Review
Chemistry, Multidisciplinary
Qing Cao, Fabian Grote, Marleen Hussmann, Siegfried Eigler
Summary: This review article focuses on the chemistry and physics of intercalated layered 2D materials, particularly intercalated bilayer and few-layer systems. It discusses the importance of intercalated graphene and transition metal dichalcogenides, describes various synthetic methods and current research directions, and provides an outlook on the future of this emerging field of research.
NANOSCALE ADVANCES
(2021)
