Nanshu Lu

The University of Texas at Austin

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Trends

Author Order

Document Type

Co-Authors

Dae‐Hyeong Kim

Seoul National University

Shutao Qiao

The University of Texas at Austin

Liu Wang

Hebei University of Technology

Zhaohe Dai

Peking University

Hongwoo Jang

The University of Texas at Austin

Taeghwan Hyeon

Institute for Basic Science

Zhigang Suo

Harvard University

John A. Rogers

Northwestern University

Deji Akinwande

The University of Texas at Austin

Shixuan Yang

Dalian University of Technology

Cooperative Institutions

The University of Texas at Austin

175

Seoul National University

104

Institute for Basic Science

Chinese Academy of Sciences

Harvard University

Massachusetts Institute of Technology

University of Illinois Urbana-Champaign

Institute of Electrical and Electronics Engineers

Stanford University

Tsinghua University

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

A Review on Mechanics and Mechanical Properties of 2D Materials - Graphene and Beyond

arXiv (Cornell University) (2016)

Deji Akinwande Christopher J. Brennan J. Scott Bunch Philip Egberts Jonathan R. Felts

Since the first successful synthesis of graphene just over a decade ago, a variety of two-dimensional (2D) materials (e.g., transition metal-dichalcogenides, hexagonal boron-nitride, etc.) have been discovered. Among the many unique and attractive properties of 2D materials, mechanical properties play important roles in manufacturing, integration and performance for their potential applications. Mechanics is indispensable in the study of mechanical properties, both experimentally and theoretically. The coupling between the mechanical and other physical properties (thermal, electronic, optical) is also of great interest in exploring novel applications, where mechanics has to be combined with condensed matter physics to establish a scalable theoretical framework. Moreover, mechanical interactions between 2D materials and various substrate materials are essential for integrated device applications of 2D materials, for which the mechanics of interfaces (adhesion and friction) has to be developed for the 2D materials. Here we review recent theoretical and experimental works related to mechanics and mechanical properties of 2D materials. While graphene is the most studied 2D material to date, we expect continual growth of interest in the mechanics of other 2D materials beyond graphene.

Hexagonal boron nitride

10.48550/arxiv.1611.01555

Cite

Citations (0)

High-Performance, Highly Bendable MoS₂ Transistors with High-K Dielectrics for Flexible Low-Power Systems

ACS Nano (2013)

Hsiao-Yu Chang Shixuan Yang Jong‐Ho Lee Li Tao Wan-Sik Hwang

While there has been increasing studies of MoS2 and other two-dimensional (2D) semiconducting dichalcogenides on hard conventional substrates, experimental or analytical studies on flexible substrates has been very limited so far, even though these 2D crystals are understood to have greater prospects for flexible smart systems. In this article, we report detailed studies of MoS2 transistors on industrial plastic sheets. Transistor characteristics afford more than 100x improvement in the ON/OFF current ratio and 4x enhancement in mobility compared to previous flexible MoS2 devices. Mechanical studies reveal robust electronic properties down to a bending radius of 1 mm which is comparable to previous reports for flexible graphene transistors. Experimental investigation identifies that crack formation in the dielectric is the responsible failure mechanism demonstrating that the mechanical properties of the dielectric layer is critical for realizing flexible electronics that can accommodate high strain. Our uniaxial tensile tests have revealed that atomic-layer-deposited HfO2 and Al2O3 films have very similar crack onset strain. However, crack propagation is slower in HfO2 dielectric compared to Al2O3 dielectric, suggesting a subcritical fracture mechanism in the thin oxide films. Rigorous mechanics modeling provides guidance for achieving flexible MoS2 transistors that are reliable at sub-mm bending radius.

Bend radius

Flexible Electronics

10.1021/nn401429w

Cite

Citations (465)

Extremely Vivid, Highly Transparent, and Ultrathin Quantum Dot Light‐Emitting Diodes

Advanced Materials (2017)

Moon Kee Choi Jiwoong Yang Dong Chan Kim Zhaohe Dai Junhee Kim

Displaying information on transparent screens offers new opportunities in next-generation electronics, such as augmented reality devices, smart surgical glasses, and smart windows. Outstanding luminance and transparency are essential for such "see-through" displays to show vivid images over clear background view. Here transparent quantum dot light-emitting diodes (Tr-QLEDs) are reported with high brightness (bottom: ≈43 000 cd m-2 , top: ≈30 000 cd m-2 , total: ≈73 000 cd m-2 at 9 V), excellent transmittance (90% at 550 nm, 84% over visible range), and an ultrathin form factor (≈2.7 µm thickness). These superb characteristics are accomplished by novel electron transport layers (ETLs) and engineered quantum dots (QDs). The ETLs, ZnO nanoparticle assemblies with ultrathin alumina overlayers, dramatically enhance durability of active layers, and balance electron/hole injection into QDs, which prevents nonradiative recombination processes. In addition, the QD structure is further optimized to fully exploit the device architecture. The ultrathin nature of Tr-QLEDs allows their conformal integration on various shaped objects. Finally, the high resolution patterning of red, green, and blue Tr-QLEDs (513 pixels in.-1 ) shows the potential of the full-color transparent display.

10.1002/adma.201703279

Cite

Citations (186)

Modular and Reconfigurable Wireless E‐Tattoos for Personalized Sensing

Advanced Materials Technologies (2019)

Hyoyoung Jeong Liu Wang Taewoo Ha Ruchika Mitbander Xiangxing Yang

Abstract In the past few years, ultrathin and ultrasoft epidermal electronics (a.k.a. e‐tattoos) emerged as the next‐generation wearables for telemedicine, mobile health, performance tracking, human‐machine interface (HMI), and so on. However, it is not possible to build an all‐purpose e‐tattoo that can accommodate such a wide range of applications. Thus, the design, fabrication, and validation of modular and reconfigurable wireless e‐tattoos for personalized sensing are reported. Such e‐tattoos feature a multilayer stack of stretchable layers of distinct functionalities—a near field communication (NFC) layer capable of wireless power harvesting and data transmission, a functional circuit layer, and a passive electrode/sensor layer. These layers can be disassembled and swapped out multiple times to form different e‐tattoos of different sensing capabilities. Such modular and wireless e‐tattoos can be rapid‐prototyped via a dry, digital, and cost‐effective fabrication process—the “cut‐solder‐paste” process. They have been successfully applied to wirelessly measure a variety of biometrics.

Wearable Technology

Interface (matter)

10.1002/admt.201900117

Cite

Citations (99)

On-scalp printing of personalized electroencephalography e-tattoos

Luize Scalco de Vasconcelos Yichen Yan Pukar Maharjan Satyam Kumar Minsu Zhang

10.1016/j.celbio.2024.100004

Cite

Citations (0)

Bio-integrated electronics

Nanshu Lu Pulin Wang

Strategies for bio-integrated electronics must overcome challenges associated with the mismatch between the hard, planar surfaces of brittle semiconductor wafers and the soft, curvilinear tissues of timely dynamic biological systems. This paper discusses the successful structural design, fabrication and bio-integration of tissue-like electronics that can intimately conform to biological tissues and deform with the tissues in a mechanically invisible manner. Examples including epidermal electronics, instrumented balloon catheters, and smart finger tubes will be discussed to manifest our multidisciplinary research at the boundary of electronics, mechanics, materials, and biomedicine.

Stretchable electronics

Flexible Electronics

10.1109/icicdt.2014.6838615

Cite

Citations (0)

A 0.025-mm² 0.8-V 78.5-dB SNDR VCO-Based Sensor Readout Circuit in a Hybrid PLL-$\Delta\Sigma$ M Structure

IEEE Journal of Solid-State Circuits (2019)

Wenda Zhao Shaolan Li Biying Xu Xiangxing Yang Xiyuan Tang

This article presents a capacitively coupled voltage-controlled oscillator (VCO)-based sensor readout featuring a hybrid phase-locked loop (PLL)-ΔΣ modulator structure. It leverages phase-locking and phase-frequency detector (PFD) array to concurrently perform quantization and dynamic element matching (DEM), much-reducing hardware/power compared with the existing VCO-based readouts' counting scheme. A low-cost in-cell data-weighted averaging (DWA) scheme is presented to enable a highly linear tri-level digital-to-analog converter (DAC). Fabricated in 40-nm CMOS, the prototype readout achieves 78-dB SNDR in 10-kHz bandwidth, consuming 4.68 μW and 0.025-mm ² active area. With 172-dB Schreier figure of merit, its efficiency advances the state-of-the-art VCO-based readouts by 50×.

Figure of Merit

Delta-sigma modulation

10.1109/jssc.2019.2959479

Cite

Citations (49)

Mechanics of Bio-Conformable Electronics

Nanshu Lu

Conformable matrix

10.26226/morressier.5f5f8e69aa777f8ba5bd6116

Cite

Citations (0)

Long-Term Modeling and Monitoring of Neuromusculoskeletal System Performance Using Tattoo-Like EMG Sensors

International Journal of Prognostics and Health Management (2023)

Kaiwen Yang Luke Nicolini Irene Kuang Nanshu Lu Dragan Djurdjanović

This paper introduces stretchable, long-term wearable, tattoo-like dry surface electrodes for highly repeatable electromyography (EMG). The tattoo-like sensors are hair thin, skin compliant and can be laminated on human skin just like a temporary transfer tattoo, which enables multi-day noninvasive but intimate contact with the skin even under severe skin deformation. The new electrodes were used to facilitate a system-based approach to tracking of long-term fatiguing and recovery processes in a human neuromusculoskeletal (NMS) system, which was based on establishing an autoregressive moving average model with exogenous inputs (ARMAX model) relating signatures extracted from the surface electromyogram (sEMG) signals collected using the tattoo-like sensors, and the corresponding hand grip force (HGF) serving as the model output. Performance degradation of the relevant NMS system was evaluated by tracking the evolution of the errors of the ARMAX model established using the data corresponding to the rested (fresh) state of any given subject. Results from several exercise sessions clearly showed repeated patterns of fatiguing and resting, with a notable point that these patterns could now be quantified via dynamic models relating the relevant muscle signatures and NMS outputs.

Tracking (education)

10.36001/ijphm.2019.v10i3.2705

Cite

Citations (5)

Work of adhesion and separation between soft elastomers

Bulletin of the American Physical Society (2015)

Nanshu Lu

Source

Cite

Citations (0)