Eggshells & Eggshell Membranes- A Sustainable Resource for energy storage and energy conversion applications: A critical review.

As the world strives to achieve a sustainable future, the exploration of alternative and renewable raw materials for energy storage and energy conversion has gained significant attention. A growing trend on "Waste to Energy" approach has attained prominence. Accordingly, chicken eggshells, a residual from poultry industry, have emerged as a promising candidate due to their abundant availability, low cost, and unique physical and chemical properties. This review article presents an overview of recent advancements in utilizing eggshell waste for energy storage and energy conversion applications. It discusses the transformation of eggshells usage into functional materials, along with their performance in various energy-related applications. The potential of eggshell-based materials in improving energy efficiency and reducing environmental impact is highlighted, providing insights into the future prospects of this sustainable resource.

Potassium hydroxide treatment of layered WSe2 with enhanced electronic performances.

2D WSe2-based electronic devices have received much research interest. However, it is still a challenge to achieve high electronic performance in WSe2-based devices. In this work, we report greatly enhanced performances of different thickness WSe2 ambipolar transistors and demonstrate homogeneous WSe2 inverter devices, which are obtained by using a semiconductor processing-compatible layer removal technique via chemical removal of the surface top WOx layer formed by O2 plasma treatment. Importantly, monolayer WSe2 was realised after several consecutive removal processes, demonstrating that the single layer removal is accurate and reliable. After subsequent removal of the top layer WOx by KOH, the fabricated WSe2 field-effect transistors exhibit greatly enhanced electronic performance along with the high electron and hole mobilities of 40 and 85 cm2 V-1 s-1, respectively. Our work demonstrates that the layer removal technique is an efficient route to fabricate high performance 2D material-based electronic devices.

Polarization-Sensitive Detector Based on MoTe2/WTe2 Heterojunction for Broadband Optoelectronic Imaging.

Polarization-sensitive detectors have significant applications in modern communication and information processing. In this study. We present a polarization-sensitive detector based on a MoTe2/WTe2 heterojunction, where WTe2 forms a favorable bandgap structure with MoTe2 after forming the heterojunction. This enhances the carrier separation efficiency and photoelectric response. We successfully achieved wide spectral detection ranging from visible to near-infrared light. Specifically, under zero bias, our photodetector exhibits a responsivity (R) of 0.6 A/W and a detectivity (D*) of 3.6 × 1013 Jones for 635 nm laser illumination. Moreover, the photoswitching ratio can approach approximately 6.3 × 105. Importantly, the polarization sensitivity can reach 3.5 (5.2) at 635 (1310) nm polarized light at zero bias. This study both unveils potential for utilizing MoTe2/WTe2 heterojunctions as polarization-sensitive detectors and provides novel insights for developing high-performance optoelectronic devices.

Position-Induced Controllable Growth of Vertically Oriented Graphene Using Plasma-Enhanced Chemical Vapor Deposition.

Because the morphology of vertically oriented graphene (VG) synthesized by the plasma-enhanced chemical vapor deposition process determines the application performance of VG, morphology control is always an important part of the research. A concise correspondence between plasma and the morphology of VG is the key to investigating the morphology control of VG, which is still under research. In this study, a simple but effective parameter, position, is used to grow VG, by which the continuous morphology evolution of VG is realized. As a result, the morphology of VGs varies from a porous structure to a "wall-like" structure, thus leading to a continuous change in its hydrophobicity and thermal emissivity. An ultrahigh emissivity of 0.999 with superhydrophobicity is obtained among these VGs, showing great potential in the area of the black body and infrared thermometer. Finally, the states of active particles in plasma depending on the positions are diagnosed to investigate their relations with the morphology of VGs.

Homogeneous in-plane WSe2 P-N junctions for advanced optoelectronic devices.

Conventional doping schemes of silicon (Si) microelectronics are incompatible with atomically thick two-dimensional (2D) transition metal dichalcogenides (TMDCs), which makes it challenging to construct high-quality 2D homogeneous p-n junctions. Herein, we adopt a simple yet effective plasma-treated doping method to seamlessly construct a lateral 2D WSe2 p-n homojunction. WSe2 with ambipolar transport properties was exposed to O2 plasma to form WOx on the surface in a self-limiting process that induces hole doping in the underlying WSe2via electron transfer. Different electrical behaviors were observed between the as-exfoliated (ambipolar) region and the O2 plasma-treated (p-doped) region under electrostatic modulation of the back-gate bias (VBG), which produces a p-n in-plane homojunction. More importantly, a small contact resistance of 710 Ω µm with a p-doped region transistor mobility of ∼157 cm2 V-1 s-1 was achieved due to the transformation of Schottky contact into Ohmic contact after plasma treatment. This effectively avoids Fermi-level pinning and significantly improves the performance of photodetectors. The resultant WSe2 p-n junction device thus exhibits a high photoresponsivity of ∼7.1 × 104 mA W-1 and a superior external quantum efficiency of ∼228%. Also, the physical mechanism of charge transfer in the WSe2 p-n homojunction was analyzed. Our proposed strategy offers a powerful route to realize low contact resistance and high photoresponsivity in 2D TMDC-based optoelectronic devices, paving the way for next-generation atomic-thickness optoelectronics.

High Photoresponse Black Phosphorus TFTs Capping with Transparent Hexagonal Boron Nitride.

Black phosphorus (BP), a single elemental two-dimensional (2D) material with a sizable band gap, meets several critical material requirements in the development of future nanoelectronic applications. This work reports the ambipolar characteristics of few-layer BP, induced using 2D transparent hexagonal boron nitride (h-BN) capping. The 2D h-BN capping have several advantages over conventional Al2O3 capping in flexible and transparent 2D device applications. The h-BN capping technique was used to achieve an electron mobility in the BP devices of 73 cm2V-1s-1, thereby demonstrating n-type behavior. The ambipolar BP devices exhibited ultrafast photodetector behavior with a very high photoresponsivity of 1980 mA/W over the ultraviolet (UV), visible, and infrared (IR) spectral ranges. The h-BN capping process offers a feasible approach to fabricating n-type behavior BP semiconductors and high photoresponse BP photodetectors.

Passivated ambipolar black phosphorus transistors.

We report the first air-passivated ambipolar BP transistor formed by applying benzyl viologen, which serves as a surface charge transfer donor for BP flakes. The passivated BP devices exhibit excellent stability under both an ambient atmosphere and vacuum; their transistor performance is maintained semi-permanently. Unlike their intrinsic p-type properties, passivated BP devices present advantageous ambipolar properties with much higher electron mobility up to ∼83 cm(2) V(-1) s(-1) from 2-terminal measurement at 300 K, compared to other reported studies on n-type BP transistors. On the basis of the n-type doping effect that originated from benzyl viologen, we also systematically investigated the BP thickness dependence of our devices on electrical properties, in which we found the best electron transport performance to be attained when an ∼10 nm thick BP flake was used.