Sensitive and selective detection of acetone in human exhaled breath plays an important role the diagnosis diabetes. However, obtaining a reliable response to ppb levels avoiding cross-sensitivity due large amount moisture are still great challenges. In this work, type sensor with ultrahigh sensitivity resistance is reported. Electrospun In2O3 nanowires controllable Pt core (Pt@In2O3 core-shell nanowires) designed prepared as sensitive layers. A mesoporous silica molecular sieve further...

In a dual active bridge (DAB) dc-dc converter, modulating the phase-shift ratios can suppress reactive power and increase efficiency under non-unity voltage gain conditions. Derivation of optimal to achieve minimum is challenging because DAB operate in four different scenarios (forward/backward, buck/boost) each scenario has five operating modes. This paper first introduces transformation which be equivalent one another; then optimization only (forward/buck) required. Next, for modes...

The wide-bandgap nature of silicon carbide (SiC) makes it an excellent candidate for applications where high temperature is required. metal-oxide-semiconductor (MOS)-controlled power devices are the most favorable structure; however, widely believed that oxide on SiC physically limited, particularly at temperatures. Therefore, experimental measurements long-term reliability temperatures necessary. In this paper, time-dependent dielectric-breakdown performed state-of-the-art 4H-SiC MOS...

The dynamic on-state resistance (RDSON) behavior of commercial GaN devices is very important for a GaN-based converter. Since the zero-voltage switching techniques are popular in high-frequency power conversion, RDSON test board integrating both hard- and soft-switching circuits built this study. Two types tested compared under conditions by double-pulse multipulse modes, respectively. It has been found that their exhibit different behaviors depending on off-state voltage frequency due to...

SiC MOSFET devices have great potentials in future high temperature power electronics applications due to their possible higher thermal runaway compared with other semiconductor devices. In this paper, the stability of MOSFETs is investigated by experiments and Saber simulations. The maximum steady-state junction measured exceed 250 °C saber simulations based on experimental model estimate that temperatures are close 300 °C. addition, performance degradation during high-temperature operation...

We report a high-performance vertical GaN-on-GaN Schottky barrier diode (SBD) with planar nitridation-based termination (NT) technique. The developed NT-SBD nearly ideal contact exhibits forward current density over kA/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> , swing 10 xmlns:xlink="http://www.w3.org/1999/xlink">13</sup> and differential specific ON-resistance of 1.2 cm . breakdown voltage is boosted from 335 V for...

Controlled thin-walled nanotubes@APTES was developed as a highly selective sensor for NO₂ detection in polluted air.

Gallium nitride (GaN) power devices enable electronic systems with enhanced density and efficiency. Dynamic on-resistance (R <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ON</sub> ) degradation (or current collapse), originating from buffer trapping, surface trapping gate instability, has been regarded as a primary challenge for the lateral GaN-on-Si devices. In this paper, we present an overview discussion of mechanisms, characterizations,...

Hierarchical core–shell IrO2@NiO nanowires (NWs) have been designed through two simple steps, which combined electrospinning of IrO2 conductive core and chemical bath deposition growth ultracontinuous NiO nanoflakes. Scanning electron microscopy, transmission X-ray diffraction, energy-dispersive spectrometry mapping, photoelectron spectroscopy were employed to characterize the morphologies structures as-prepared samples, results also carefully compared with that pure nanoflowers NWs....

This paper proposes a bidirectional three-level LLC resonant converter with new pulse width and amplitude modulation control method. With different signals, it has three operation modes voltage gains. Therefore, can achieve wide gain range by switching among these modes, which is attractive for energy storage system applications needing variation. The proposed topology operates constant frequency, easy to implement digital control, soft all the switches diodes in circuit as conventional...

Searching for high-quality air electrode catalysts is the long-term goal practical application of Zn–air batteries. Here, a series coexistent composite materials (CoNi/NHCS-TUC-x) cobalt–nickel supported on nitrogen-doped hollow spherical carbon and tubular are obtained using simple pyrolysis strategy. Co Ni in composites mainly present form alloy nanoparticles, M–Nx M–Cx (M = or Ni) species, with high oxygen reduction reaction (ORR)/oxygen evolution (OER) electroactivity. The containing...

In this letter, fluorine-implanted termination (FIT) has been demonstrated in vertical GaN-on-GaN Schottky barrier diodes (SBDs). Owing to the unique feature of F ions that can become negative fixed charges GaN, electric field crowding at junction edge be mitigated and breakdown voltage (BV) GaN SBDs effectively enhanced. For SBDs, it is challenging simultaneously achieve both high BV low forward drop (V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML"...

Comprehensive utilization of cottonseeds is limited by the presence pigment glands and its inclusion gossypol. The ideal cotton has glandless seeds but a glanded plant, trait found in only few Australian wild species, including Gossypium bickii. Introgression this into cultivated species proved to be difficult. Understanding biological processes toward gland morphogenesis associated underlying molecular mechanisms will facilitate breeding varieties with plant. In study, single-cell RNA...

This Letter demonstrates a high-performance 3.3 kV-class β-Ga2O3 vertical heterojunction diode (HJD) along with an investigation into its off-state leakage mechanism. The HJD field plate assisted deep mesa (FPDM) termination was fabricated using self-aligned technique to etch the depth of 9 μm, thereby reducing electric crowding at anode edge. In addition, thick dielectric is deposited fill trench, facilitating utilization further reduce TCAD (Technology Computer Aided Design) simulations...

In this paper, a new series connection topology is introduced for silicon carbide (SiC) MOSFETs. the topology, with single external gate drive, three series-connected SiC MOSFETs are synchronously driven. The operating principle of proposed analyzed and presented. order to improve current capability module, parallel two devices also demonstrated. A 3600 V/80 series-parallel-connected configuration rows in branches constructed six 1200 V/40 discrete Switching behavior completed at 2300 V/78...

This paper presents a detailed physical analysis on the junction temperatures, thermal stabilities, and runaway effects of self-heating unipolar SiC power devices. Results reveal that risk could limit usable temperature these devices to substantially lower than 200 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">°</sup> C, regardless device size cooling method used.

Bulk traps in the high-resistivity buffer stack underneath 2-dimensional electron gas (2DEG), which can interact with high vertical electric field at OFF state, impose a critical challenge to dynamic ON-resistance (RON) of AlGaN/GaN-on-Si power devices. In this paper, impact substrate bias polarity on carrier injection/transport and buffer-induced current collapse has been investigated by using ramped transient back-gating characterizations as well TCAD simulations. High voltage applied...

This letter presents the design, prototype development, operation, and testing of an 800 kHz, 1 kW, V output boost dc-dc converter module that integrates SiC MOSFET Schottky diode die. It is observed when device loss dominated by switching loss, steady-state junction temperature can reach as high 320°C. highest self-heated operation power devices under room ambient reported in literature. The high-frequency characteristics high-temperature thermal reliability assessed are evaluated detail. A...