Article
Chemistry, Multidisciplinary
Arka Karmakar, Abdullah Al-Mahboob, Christopher E. Petoukhoff, Oksana Kravchyna, Nicholas S. Chan, Takashi Taniguchi, Kenji Watanabe, Keshav M. Dani
Summary: This study shows that nonradiative energy transfer dominates over interlayer charge transfer in type-II heterostructures formed by transition metal dichalcogenides. It also demonstrates an innovative way to increase the photoluminescence intensity of desired materials by carefully choosing the right material combination.
Article
Chemistry, Multidisciplinary
Veronica R. Policht, Mattia Russo, Fang Liu, Chiara Trovatello, Margherita Maiuri, Yusong Bai, Xiaoyang Zhu, Stefano Dal Conte, Giulio Cerullo
Summary: This study utilized two-dimensional electronic spectroscopy (2DES) to resolve interlayer electron and hole transfer processes in WS2/MoS2 heterostructures, while simultaneously uncovering optoelectronic processes such as band gap renormalization and intralayer exciton coupling.
Article
Chemistry, Multidisciplinary
Amir Muhammad Afzal, Muhammad Zahir Iqbal, Ghulam Dastgeer, Aqrab ul Ahmad, Byoungchoo Park
Summary: A novel vdWH FET composed of MoTe2 and PdSe2 has been studied for highly sensitive photodetection performance in the visible and near-infrared region, showing high rectification ratio, photoresponsivity, detectivity, and external quantum efficiency. The device exhibits rapid rise and decay times under incident light due to inter-TMD charge transfer transition, representing an outcome one order of magnitude faster than current literature values. These TMD-based vdWH FETs would improve photo-gating characteristics and provide a platform for highly sensitive photodetectors in the broad VNIR region.
Article
Nanoscience & Nanotechnology
Dayeong Kwon, Jun Young Kim, Sang-Hun Lee, Eunji Lee, Jeongyong Kim, Amit Kumar Harit, Han Young Woo, Jinsoo Joo
Summary: The characteristics of field effect transistors fabricated using two-dimensional transition-metal dichalcogenides can be modulated by surface treatment with an ionic pi-conjugated polyelectrolyte, resulting in a charge-transfer effect and enhanced photoresponsivity. The n-channel current of both the MoSe2 and WS2 FETs increased, and the photoluminescence peaks were red-shifted after treatment. The external quantum efficiency and photodetectivity of both FETs were enhanced by the charge-transfer effect.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Multidisciplinary
Shuangyan Liu, Dawei He, Congwei Tan, Shaohua Fu, Xiuxiu Han, Mohan Huang, Qing Miao, Xiaoxian Zhang, Yongsheng Wang, Hailin Peng, Hui Zhao
Summary: Research on the interlayer charge transfer properties of heterostructures formed by Bi2O2Se and WS2/MoS2 showed photoluminescence quenching and ultrafast charge transfer processes. These results demonstrate the feasibility of integrating 2D Bi2O2Se with other 2D semiconductors to fabricate heterostructures with novel charge transfer properties.
Article
Chemistry, Multidisciplinary
Seongjoon Lim, Shangke Pan, Kefeng Wang, Alexey Ushakov, Ekaterina Sukhanova, Zakhar Popov, Dmitry G. Kvashnin, Sergey Streltsov, Sang-Wook Cheong
Summary: By cleaving metallic Co-1/3 NbS2, researchers have demonstrated the ability to obtain a layer of controllable atomic charges on a periodic lattice and manipulate them to form a linear chain, which can be generalized to other combinations of intercalants and base matrices.
Article
Chemistry, Multidisciplinary
Ting Zheng, Yu-Chuan Lin, Neema Rafizadeh, David B. Geohegan, Zhenhua Ni, Kai Xiao, Hui Zhao
Summary: The charge transfer properties of van der Waals heterostructures formed by Janus and regular transition metal dichalcogenide monolayers have been studied. It is found that the charge transfer from regular to Janus monolayers is ultrafast, regardless of the direction of the Janus field. However, the charge transfer from Janus to regular layers is directional and controlled by the Janus field. The transferred carriers form interlayer excitons with extended lifetimes compared to intralayer excitons. These findings indicate that Janus structures can be utilized to create 2D heterostructures with efficient and directional charge transfer properties.
Article
Optics
Min-Soo Hwang, Hong-Gyu Park
Summary: Lithographically designed potential wells in monolayer WS2 microcavities can manipulate nonlinear transition-metal dichalcogenide polaritons and enhance the interaction strength between polaritons and the reservoir.
LIGHT-SCIENCE & APPLICATIONS
(2023)
Article
Quantum Science & Technology
Takashi Mizokawa, Alexei Barinov, Viktor Kandyba, Alessio Giampietri, Ryoya Matsumoto, Yohei Okamoto, Kou Takubo, Koji Miyamoto, Taichi Okuda, Sunseng Pyon, Hiroyuki Ishii, Kazutaka Kudo, Minoru Nohara, Naurang L. Saini
Summary: Solids undergoing symmetry breaking phase transitions often form domains of low symmetry phases with different sizes and shapes. This article presents an interesting example of a layered dichalcogenide with a triangular lattice, where symmetry breaking of electronic charge/orbital is accompanied by the formation of striped domains and exotic surface states with peculiar spin textures. The study provides insights into the interplay between symmetry breaking, surface electronic structure, and the spin state.
ADVANCED QUANTUM TECHNOLOGIES
(2022)
Article
Nanoscience & Nanotechnology
Xinhui yang, Shunhui Zhang, Zhengwei Zhang, Jianting Lin, Xiaoliang Liu, Zhiwei Huang, Liqiang Zhang, Wenchen Luo, Jun He, Xiaoming Yuan
Summary: A non-destructive approach is demonstrated to construct vertical heterostructures of CsPbI2Br/TMDC through dual-source thermal evaporation. The type-II band alignment between CsPbI2Br and monolayer WSe2 or WS2 enables fast charge separation and quenches photon emission intensity. The high carrier transfer efficiency and rate of CsPbI2Br/WSe2 heterostructures make the deposition of perovskite on TMDC layers significant for optoelectronic device applications. Moreover, a broad low energy peak is observed in the CsPbI2Br/TMDC heterostructures, indicating interlayer exciton effects.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2023)
Article
Optics
Battulga Munkhbat, Betul Kucukoz, Denis G. Baranov, Tomasz J. Antosiewicz, Timur O. Shegai
Summary: Transition metal dichalcogenides (TMDs), including semiconducting WS2, in-plane anisotropic ReS2, and metallic TaSe2, TaS2, and NbSe2, have attracted significant attention due to their exceptional optical, excitonic, mechanical, and electronic properties. Nanostructured multilayer TMDs, with their high refractive indices and optical anisotropy, show promise for nanophotonic applications. Advanced nanofabrication strategies, including careful selection of resists for electron beam lithography and etching methods, are discussed, with a specific focus on non-conductive substrates such as SiO2. These TMD-based nanostructures have the potential to impact high-index nanophotonics, plasmonics, and on-chip optical circuits.
LASER & PHOTONICS REVIEWS
(2023)
Article
Multidisciplinary Sciences
Elyse Barre, Ouri Karni, Erfu Liu, Aidan L. O'Beirne, Xueqi Chen, Henrique B. Ribeiro, Leo Yu, Bumho Kim, Kenji Watanabe, Takashi Taniguchi, Katayun Barmak, Chun Hung Lui, Sivan Refaely-Abramson, Felipe H. da Jornada, Tony F. Heinz
Summary: Interlayer excitons, electron-hole pairs bound across two monolayer van der Waals semiconductors, offer promising electrical tunability and localizability. The dielectric response of interlayer excitons was directly measured using their static electric dipole moment, and an intrinsic radiative lifetime and transition characteristics were determined. This study identifies a momentum-indirect emission mechanism and emphasizes the importance of characterizing absorption for applications relying on light-matter interactions.
Article
Physics, Applied
Shasha Li, Yong Yan, Jie Li, Mengdan Qian, Chenhai Shen, Xiaohui Song, Yurong Jiang, Congxin Xia, Jingbo Li
Summary: In this study, a new type of SWIR photodetector based on In2(1-x)Sb2xSe3 material was designed and prepared, and it showed excellent photoresponse performance, indicating its potential as an important material for SWIR photodetectors.
APPLIED PHYSICS LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Jixing Cai, Huanjun Chen, Yanlin Ke, Shaozhi Deng
Summary: Capillary-force-assisted transfer is a promising method for constructing two-dimensional electronic and optoelectronic devices. However, the transfer mechanism and integrity of the method need further improvement. In this study, the authors developed a capillary-force-assisted transfer method with improved integrity and utilization. They also derived a water transport model between different surfaces and analyzed the capillary adhesion and invasion mechanisms. The study highlights the potential of this method for fabricating van der Waals structures based on two-dimensional atomic crystals.
Article
Chemistry, Multidisciplinary
Zhixing Lu, Songjun Hou, Rongjian Lin, Jie Shi, Qingqing Wu, Shiqiang Zhao, Luchun Lin, Chun Tang, Yang Yang, Colin J. Lambert, Wenjing Hong
Summary: In this study, semimetallic transition metal dichalcogenides (TMDCs) 1T-WTe2 were used as electrodes to fabricate WTe2/metalated tetraphenyl-porphyrin (M-TPP)/WTe2 junctions via van der Waals interaction. Compared to chemically bonded Au/M-TPP/Au junctions, the conductance of these M-TPP van der Waals molecular junctions was enhanced by 736%. Moreover, the WTe2/M-TPP/WTe2 junctions exhibited a tunable conductance range of 10^(-3.29) to 10^(-4.44) G through single-atom control, recording the widest tunable range of conductance for M-TPP molecular junctions. This work demonstrates the potential of two-dimensional TMDCs in constructing highly tunable and conductive molecular devices.
Article
Nanoscience & Nanotechnology
Shizhou Jiang, Dmitry Lebedev, Loren Andrews, J. Tyler Gish, Thomas W. Song, Mark C. Hersam, Oluwaseyi Balogun
Summary: Two-dimensional (2D) semiconductors with ambient encapsulation exhibit unique physical properties desirable for various applications. However, limited studies have been conducted on the in-plane thermal conductivity measurements in encapsulated 2D semiconductors. To address this challenge, the authors integrated the FDTR and OTRS techniques in the same experimental platform.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Nanoscience & Nanotechnology
Alfred J. Baca, Michael D. Garrison, Lidia Kuo, Feiyu Xu, Lawrence C. Baldwin, Alexander S. Hyla, Michael R. Zachariah, Mark C. Hersam
Summary: This study investigates the effectiveness of ethyl cellulose (EC) as an alternative to nitrocellulose (NC) in enhancing the reactivity of ammonium perchlorate (AP). The results show that graphene (Gr) and hexagonal boron nitride (hBN) dispersed in EC have minimal effect on AP's decomposition behavior, while molybdenum disulfide (MoS2) dispersed in EC significantly enhances the decomposition of AP. This study highlights the unique roles of the disperagent and 2D nanomaterial in tuning the thermal decomposition of AP.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Editorial Material
Chemistry, Multidisciplinary
Mathieu Salanne, Jillian M. Buriak, Xiaodong Chen, William Chueh, Mark C. Hersam, Raymond E. Schaak
Article
Chemistry, Multidisciplinary
Nathan P. Bradshaw, Zoheb Hirani, Lidia Kuo, Siyang Li, Nicholas X. Williams, Vinod K. Sangwan, Lindsay E. Chaney, Austin M. Evans, William R. Dichtel, Mark C. Hersam
Summary: Covalent organic frameworks (COFs) are promising materials for various applications, and the ability to directly print COFs into desired geometries is crucial for their optimization and deployment. This study presents a method to print COFs with micron-scale resolution using a solution-processable colloidal ink. The ink formulation, based on low-volatility solvent benzonitrile, allows for homogeneous printed COF film morphologies. The ink is also compatible with other nanomaterials, enabling the integration of COFs into printable nanocomposite films. Proof-of-concept experiments demonstrate the successful integration of boronate-ester COFs with carbon nanotubes (CNTs) to create printable COF-CNT nanocomposite films with enhanced temperature sensing performance.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Linfei Li, Jeremy F. Schultz, Sayantan Mahapatra, Xiaolong Liu, Xu Zhang, Mark C. Hersam, Nan Jiang
Summary: Ultra-high vacuum tip-enhanced Raman spectroscopy (UHV-TERS) was used to chemically characterize bilayer borophene at the atomic level. The achieved results validated the three-dimensional lattice geometry of bilayer borophene and demonstrated its enhanced chemical stability compared to its monolayer counterpart. This work not only provides fundamental chemical insight into bilayer borophene but also establishes UHV-TERS as a powerful tool to probe atomic-level interlayer bonding and surface reactivity of low-dimensional materials.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Physics, Applied
G. Berti, C. G. Torres-Castanedo, D. P. Goronzy, M. J. Bedzyk, M. C. Hersam, C. Kopas, J. Marshall, M. Iavarone
Summary: Niobium thin films are important for superconducting microwave resonators used in quantum systems. The understanding of loss mechanisms affecting the performance of superconducting devices is still limited. This study investigates the Nb/substrate interface by comparing the local superconducting properties of Nb films grown on hydrogen-passivated H:Si(111) substrates and typical Si(001) substrates. The results show that the Nb films grown on H:Si(111) substrates have a smoother and less defective interface, exhibiting more uniform superconducting properties and less quasiparticle broadening.
APPLIED PHYSICS LETTERS
(2023)
Article
Chemistry, Multidisciplinary
David W. Burke, Raghunath R. Dasari, Vinod K. Sangwan, Alexander K. Oanta, Zoheb Hirani, Chloe E. Pelkowski, Yongjian Tang, Ruofan Li, Daniel C. Ralph, Mark C. Hersam, Stephen Barlow, Seth R. Marder, William R. Dichtel
Summary: Researchers synthesized a new controllable oriented two-dimensional covalent organic framework (COF), named OTPA-BDT, via transimination reactions between benzophenone-imine-protected azatriangulenes (OTPA) and benzodithiophene dialdehydes (BDT). The material exhibits tunable semiconductor properties with a Dirac-cone-like band structure, making it an ideal candidate for next-generation flexible electronics. After orientation and doping, the OTPA-BDT COF films demonstrate high electrical conductivities of up to 1.2 x 10(-1) S cm(-1), the highest reported for imine-linked 2D COFs to date.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Nanoscience & Nanotechnology
Carlos G. Torres-Castanedo, Guennadi Evmenenko, Norman S. Luu, Paul Masih Das, Woo Jin Hyun, Kyu-Young Park, Vinayak P. Dravid, Mark C. Hersam, Michael J. Bedzyk
Summary: In this study, the structural and interfacial evolution of single-crystal epitaxial LiMn2O4 (111) thin-films during cycling were investigated using synchrotron in situ X-ray diffraction and reflectivity. Cyclic voltammetry experiments were performed in two different electrolyte systems, and the results showed that the ionic liquid electrolyte exhibited better stability compared to the conventional electrolyte, attributed to the absence of Mn dissolution in the ionic liquid.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Sonal V. V. Rangnekar, Vinod K. K. Sangwan, Mengru Jin, Maryam Khalaj, Beata M. M. Szydlowska, Anushka Dasgupta, Lidia Kuo, Heather E. E. Kurtz, Tobin J. J. Marks, Mark C. C. Hersam
Summary: Electroluminescence from molybdenum disulfide (MoS2) nanosheet films has been demonstrated by using a monolayer-rich MoS2 ink produced by electrochemical intercalation and megasonic exfoliation. The megasonicated MoS2 films retain their direct bandgap character in electrically percolating thin films even following multistep solution processing. This work establishes megasonicated MoS2 inks as an additive manufacturing platform for flexible, patterned, and miniaturized light sources.
Article
Chemistry, Multidisciplinary
Lindsay E. Chaney, Woo Jin Hyun, Maryam Khalaj, Janan Hui, Mark C. Hersam
Summary: In this study, mechanically flexible micro-supercapacitor arrays were created through high-speed screen printing of conductive graphene electrodes and a high-temperature hexagonal boron nitride (hBN) ionogel electrolyte. The resulting hBN ionogel electrolyte, which combines the exceptional dielectric properties of 2D hBN with the high ionic conductivity of ionic liquids, enables micro-supercapacitors with exceptional areal capacitances approaching 1 mF cm(-2). These printed micro-supercapacitors can operate at unprecedentedly high temperatures up to 180°C, thanks to the high-temperature stability of the hBN ionogel electrolyte. This makes them particularly promising for applications in harsh environments such as underground exploration, aviation, and electric vehicles.
ADVANCED MATERIALS
(2023)
Article
Construction & Building Technology
Panagiotis A. Danoglidis, Cory M. Thomas, Myrsini E. Maglogianni, Mark C. Hersam, Maria S. Konsta-Gdoutos
Summary: Portland cement-based nanocomposites with low volume fractions of hBN nanoplatelets were prepared successfully through exfoliation and functionalization of hBN using ball milling and sonicated-assisted dispersion. AFM and Raman analysis were utilized to evaluate the properties of hBN nanoplatelets, while FTIR was used to identify the functional groups on functionalized hBN. The results demonstrated that the functionalization process successfully achieved few-layer thicknesses of hBN nanoplatelets, leading to suspensions with high colloidal stability. The interaction between hydroxyl and carboxyl groups on the hBN surface and Ca2+ ions of CSH improved the load-transfer efficiency, resulting in significant enhancement in flexural strength, compressive strength, Young's modulus, and fracture energy of the hBN reinforced cementitious composites.
CEMENT & CONCRETE COMPOSITES
(2023)
Article
Materials Science, Multidisciplinary
M. Iqbal Bakti Utama, Anushka Dasgupta, Riddhi Ananth, Emily A. Weiss, Tobin J. Marks, Mark C. Hersam
Summary: Quantum information science has the potential to revolutionize computing, communication, and sensing. Photonic systems, particularly those based on two-dimensional (2D) materials, show promise in producing mobile qubits for high-speed information transmission. Recent developments in mixed-dimensional heterostructures involving 2D materials have demonstrated the potential for robust single-photon emitters, and the integration with other materials offers further opportunities for tuning emission properties.
Article
Chemistry, Physical
Youjin Lee, Soo Hyun Lee, Sun Kyung Han, Jiheon Park, Dongwook Lee, Daniel J. Preston, In Soo Kim, Mark C. Hersam, Yongwoo Kwon, Bonggeun Shong, Won-Kyu Lee
Summary: This study reports an approach for the activation of electrochemically inert MoTe2 to produce a low-cost and scalable hydrogen evolution reaction catalyst for water splitting. Strain engineering enhances the HER performance of MoTe2, and in operando activation of the flakes further amplifies the electrochemical activity.
ACS ENERGY LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Elisa Trippodo, Vincenzo Campisciano, Liang-Wen Feng, Yao Chen, Wei Huang, Joaquin M. Alzola, Ding Zheng, Vinod K. Sangwan, Mark C. Hersam, Michael R. Wasielewski, Bruno Pignataro, Francesco Giacalone, Tobin J. Marks, Antonio Facchetti
Summary: Organic solar cells based on donor-acceptor blends have shown great potential in efficiency improvement, but performance degradation is still a major obstacle for commercialization. Ternary solar cells with fullerene acceptors as the third component exhibit enhanced stability with over 90% retention of initial power conversion efficiency even after 6 months of storage. This improved stability is attributed to a more robust blend morphology that reduces charge recombination in the aging process.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Nathan P. Bradshaw, Zoheb Hirani, Lidia Kuo, Siyang Li, Nicholas X. Williams, Vinod K. Sangwan, Lindsay E. Chaney, Austin M. Evans, William R. Dichtel, Mark C. Hersam
Summary: This paper presents a method of aerosol jet printing of COFs with micron-scale resolution using a pre-synthesized colloidal ink. The ink formulation enables the integration of COFs with other colloidal nanomaterials to form printable nanocomposite films, resulting in high-sensitivity temperature sensors.
ADVANCED MATERIALS
(2023)