Micro- and nano air vehicles are defined as “extremely small and ultra-lightweight air vehicle systems” with a maximum wingspan length of 15 cm and a weight less than 20 grams. Here, we provide a review of the current state of the art and identify the challenges of design and fabrication. Different configurations are evaluated, such as fixed wings, rotary wings, and flapping wings. The main advantages and drawbacks for each typology are identified and discussed. Special attention is given to rotary-wing vehicles (helicopter concept); including a review of their main structures, such as the airframe, energy storage, controls, and communications systems. In addition, a review of relevant sensors is also included. Examples of existing and future systems are also included. Micro- and nano-vehicles with rotary wings and rechargeable batteries are dominating. The flight times of current systems are typically around 1 hour or less due to the limited energy storage capabilities of the used rechargeable batteries. Fuel cells and ultra capacitors are promising alternative energy supply technologies for the future. Technology improvements, mainly based on micro- and nanotechnologies, are expected to continue in an evolutionary way to improve the capabilities of future micro- and nano air vehicles, giving improved flight times and payload capabilities.

Diabetes is a metabolic disorder that results in human body due to insulin deficiency, insulin resistance or both. In the management of diabetes, glucose monitoring technology has been used for the last three decades. The aim of this review article is to describe concise and organized information about different techniques of non-invasive continuous blood glucose monitoring. Many research groups have been working to develop wearable sensors for continuous blood glucose monitoring, but at present, there are to our knowledge no commercially successful non-invasive glucose monitors on the market. To achieve an acceptable sensor system, a glucose sensor should have accuracy better than 15mg/dl (0.8 mmol/l).In future development, continuous glucose sensor systems may become predictable, selective, reliable and acceptable for patient use.

We demonstrate high aspect ratio silicon nanorod arrays by cyclic deep reactive ion etching (DRIE) process as a scaffold to enhance the energy density of a Si-based supercapacitor. By unique atomic layer deposition (ALD) technology, a conformal nano layer of TiN was deposited on the silicon nanorod arrays as the active material.The TiN coated silicon nanorods as a supercapacitor electrode lead to a 6 times improvement in capacitance compared to flat TiN film electrode.

Anodic bonding of silicon wafers by sputter deposited glass films, silicon-to-silicon anodic bonding, is presented as a promising sealing method in microengineering. A reliable process for wafer-to-wafer bonding is described and data concerning yield and bonding strength are given. Cathodic bonding is reported in a discussion about the bonding mechanism. Different sputter deposited and annealed Pyrex 7740 layers are evaluated as sealing material. Some advantages of silicon-to-silicon anodic bonding as a mounting method for micromechanical sensors are quantified.

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Within a decade, black phosphorus has become an important 2D material for sustainable energy areas and bioapplications due to its great electronic properties and biocompatibility. Pristine black phosphorus suffers from intrinsic shortages like rapid degradation and poor solubility, which require physical and chemical tuning methods. There also lacks an effective approach to synthesize single-crystal black phosphorus with large areas. This review article provides a forward-looking overview of significance, mechanism studies, status quo, and outlooks of defect-tailoring and surface functionalization in black phosphorus; the prior focuses on the lattice while the latter focuses on the surface. Particularly, both approaches can alter chemical and electronic properties such as air stability, solubility, carrier mobility, and band gap. Functionalization further enables the BP surface to immobilize various biomarkers and medical molecules, which largely boost its future applications in biosensors and theranotics. Finally, we discuss some unresolved issues and future applications, especially in tuning BP especially in BP synthesis, atomic modification methods, and bioapplications.

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