There are growing concerns over the environmental, climate, and health impacts caused by using non-renewable fossil fuels. The utilization of green energy, including solar and wind power, is believed to be one of the most promising alternatives to support more sustainable economic growth. In this regard, lithium-ion batteries (LIBs) can play a critically important role. To further increase the energy and power densities of LIBs, silicon anodes have been intensively explored due to their high capacity, low operation potential, environmental friendliness, and high abundance. The main challenges for the practical implementation of silicon anodes, however, are the huge volume variation during lithiation and delithiation processes and the unstable solid-electrolyte interphase (SEI) films. Recently, significant breakthroughs have been achieved utilizing advanced nanotechnologies in terms of increasing cycle life and enhancing charging rate performance due partially to the excellent mechanical properties of nanomaterials, high surface area, and fast lithium and electron transportation. Here, the most recent advance in the applications of 0D (nanoparticles), 1D (nanowires and nanotubes), and 2D (thin film) silicon nanomaterials in LIBs are summarized. The synthetic routes and electrochemical performance of these Si nanomaterials, and the underlying reaction mechanisms are systematically described.

Silicon-based Nanomaterials for Lithium-Ion Batteries - A Review

The field of cantilever-based sensing emerged in the mid-1990s and is today a well-known technology for label-free sensing which holds promise as a technique for cheap, portable, sensitive and highly parallel analysis systems. The research in sensor realization as well as sensor applications has increased significantly over the past 10 years. In this review we will present the basic modes of operation in cantilever-like micromechanical sensors and discuss optical and electrical means for signal transduction. The fundamental processes for realizing miniaturized cantilevers are described with focus on silicon- and polymer-based technologies. Examples of recent sensor applications are given covering such diverse fields as drug discovery, food diagnostics, material characterizations and explosives detection.

http://iopscience.iop.org/article/10.1088/0034-4885/74/3/036101/pdf

Cantilever-like micromechanical sensors

In recent years, GaN nanorods are emerging as a very promising novel route toward devices for nano-optoelectronics and nano-photonics. In particular, core-shell light emitting devices are thought to be a breakthrough development in solid state lighting, nanorod based LEDs have many potential advantages as compared to their 2 D thin film counterparts. In this paper, we review the recent developments of GaN nanorod growth, characterization, and related device applications based on GaN nanorods. The initial work on GaN nanorod growth focused on catalyst-assisted and catalyst-free statistical growth. The growth condition and growth mechanisms were extensively investigated and discussed. Doping of GaN nanorods, especially p-doping, was found to significantly influence the morphology of GaN nanorods. The large surface of 3 D GaN nanorods induces new optical and electrical properties, which normally can be neglected in layered structures. Recently, more controlled selective area growth of GaN nanorods was realized using patterned substrates both by metalorganic chemical vapor deposition (MOCVD) and by molecular beam epitaxy (MBE). Advanced structures, for example, photonic crystals and DBRs are meanwhile integrated in GaN nanorod structures. Based on the work of growth and characterization of GaN nanorods, GaN nanoLEDs were reported by several groups with different growth and processing methods. Core/shell nanoLED structures were also demonstrated, which could be potentially useful for future high efficient LED structures. In this paper, we will discuss recent developments in GaN nanorod technology, focusing on the potential advantages, but also discussing problems and open questions, which may impose obstacles during the future development of a GaN nanorod based LED technology.

GaN based nanorods for solid state lighting

This paper provides an overview of the Industrial Internet with the emphasis on the architecture, enabling technologies, applications, and existing challenges. The Industrial Internet is enabled by recent rising sensing, communication, cloud computing, and big data analytic technologies, and has been receiving much attention in the industrial section due to its potential for smarter and more efficient industrial productions. With the merge of intelligent devices, intelligent systems, and intelligent decisioning with the latest information technologies, the Industrial Internet will enhance the productivity, reduce cost and wastes through the entire industrial economy. This paper starts by investigating the brief history of the Industrial Internet. We then present the 5C architecture that is widely adopted to characterize the Industrial Internet systems. Then, we investigate the enabling technologies of each layer that cover from industrial networking, industrial intelligent sensing, cloud computing, big data, smart control, and security management. This provides the foundations for those who are interested in understanding the essence and key enablers of the Industrial Internet. Moreover, we discuss the application domains that are gradually transformed by the Industrial Internet technologies, including energy, health care, manufacturing, public section, and transportation. Finally, we present the current technological challenges in developing Industrial Internet systems to illustrate open research questions that need to be addressed to fully realize the potential of future Industrial Internet systems.

Industrial Internet: A Survey on the Enabling Technologies, Applications, and Challenges

Fabrication of monolithic lattice-mismatched semiconductor heterostructures with limited area regions having upper portions substantially exhausted of threading dislocations, as well as fabrication of semiconductor devices based on such lattice-mismatched heterostructures.

Lattice-Mismatched Semiconductor Structures with Reduced Dislocation Defect Densities and Related Methods for Device Fabrication

A silicon resonant cantilever sensor is developed for detection of airborne nanoparticles (NPs) by monitoring the change in resonant frequency induced by an additional mass of trapped NPs. A piezoelectric stack actuator and a piezoresistive strain gauge are involved in the sensor system in order to actuate and detect the oscillation of cantilever sensor, respectively. An electrostatic precipitator is employed to trap the NPs on the cantilever surface. The proposed sensor reveals a mass sensitivity of 10 Hz/ng and a quality factor of 1206 while operated in the fundamental flexural mode. As necessary for an application under workplace conditions the limitations of the sensor sensitivity imposed by the environment are investigated, i.e., the influences of temperature, relative humidity, and pressure on the sensor are measured.

Airborne engineered nanoparticle mass sensor based on a silicon resonant cantilever

The electrochemical capacitance-voltage (ECV) technique was used to measure the carrier concentration profiles in Si Using the conventional parallel-equivalent circuit model of the Schottky junction to describe the electrolyte-silicon barrier we found excellent agreement between ECV and four-point probe analyses within ±10 to 20% for bulk Si uniformly doped p- and n-type from 10 12 to 10 18 cm -3  In this concentration range accuracy limits are determined mainly by the precise measurement of the area of the electrolyte-Si contact For the anodic etching of Si, a constant effective dissolution valence of z=37 was used throughout the measurements Investigations with isotype and anisotype doping transitions were performed employing ECV and other profiling techniques for comparison

Doping Profile Analysis in Si by Electrochemical Capacitance‐Voltage Measurements

Design, fabrication and test of cantilever-type sensors for active micro force calibration are described. The cantilever comprises a probing tip at its free end where a force can be applied which is measured using a piezoresistive strain gauge at the cantilever suspension. The stiffness of the cantilever is approximately given by the spring constant of a beam with a rectangular cross section as confirmed by finite element modelling. Prototypes with a stiffness of 0.66 N m−1 and 7.7 N m−1 are realized using standard silicon bulk micromachining technology. Testing is performed using a high-resolution micro force measuring set-up. In either case a highly linear relationship between the gauge output voltage and the probing force is revealed in the µN range. Low scatter and drift corresponding to a standard deviation of ±0.22% was found for the resulting force sensitivity.

https://iopscience.iop.org/article/10.1088/0960-1317/13/4/325/pdf

Piezoresistive cantilever as portable micro force calibration standard

Silicon is investigated as a low-cost, Earth-abundant thermoelectric material for high-temperature applications up to 900 K. For the calculation of module design the Seebeck coefficient and the electrical as well as thermal properties of silicon in the high-temperature range are of great importance. In this study, we evaluate the thermoelectric properties of low-, medium-, and high-doped silicon from room temperature to 900 K. In so doing, the Seebeck coefficient, the electrical and thermal conductivities, as well as the resulting figure of merit ZT of silicon are determined.

https://www.tpbin.com/Uploads/Subjects/6bdd0f54-f7dc-4600-8e44-2f0392fe7a92.pdf

Thermoelectric Properties of High-Doped Silicon from Room Temperature to 900 K

This work demonstrates mass measurement of airborne titanium dioxide (TiO2) engineered nanoparticles (ENPs) using silicon resonant nanopillar sensors by monitoring resonant frequency shifts induced by the mass of trapped ENPs. Inductively coupled plasma (ICP) cryogenic dry etching and thermal oxidation have been used in the sensor fabrication. A piezo shear actuator and an electrostatic precipitator are utilized to excite the nanopillars in resonant mode and collect the flowing TiO2 ENPs, respectively. By using the fundamental bending frequency, the sensor can achieve a mass sensitivity of 7.22 Hz/fg, which enables its application to a nanobalance to detect airborne ENPs in the femtogram mass range. Two methods of ENP removals (i.e., polydimethylsiloxane (PDMS) and ultrasonic cleanings) have also been performed to remove the adhered ENPs, thus efficiently extending the operating life of the sensor. This developed sensor is targeted to be implemented as a handheld ENP monitoring device at workplaces.

Erwin Peiner

Papers

Airborne engineered nanoparticle mass sensor based on a silicon resonant cantilever

Doping Profile Analysis in Si by Electrochemical Capacitance‐Voltage Measurements

Piezoresistive cantilever as portable micro force calibration standard

Thermoelectric Properties of High-Doped Silicon from Room Temperature to 900 K

Silicon resonant nanopillar sensors for airborne titanium dioxide engineered nanoparticle mass detection