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Mastication is an essential and preliminary step of the digestion process involving fragmentation and mixing of food. Controlled muscle movement of jaws with teeth executes crushing, leading towards fragmentation of food particles. Understanding various parameters involved with the process is essential to solve any biomedical complication in the area of interest. However, exploring and analyzing such process flow through an experimental route is challenging and inefficient. Computational techniques such as discrete element numerical modeling can effectively address such problems. The current work employs the Discrete Element Method (DEM) as a numerical modeling technique to simulate the human mastication process. Tavares and Ab-T10 breakage models coupled with Gaudin Schumann and Incomplete Beta fragment distribution models have been implemented to analyze the fragmental distribution of food particles. The effect of particle shape (spherical, polyhedron, and faceted cylinder), size (aspect ratio), and orientation (vertical and horizontal) on breakage and fragment distribution is analyzed. To account for the elastic-plastic behavior and moisture content in food particles, modifications has been made in breakage models by incorporating numerical softening factor and adhesion force. The study demonstrates how numerical modeling techniques can be utilized to analyze the mastication process involving multiple process parameters., (© 2024 John Wiley & Sons Ltd.)

A lot of experimental studies are conducted on theoretically predicted thermoelectric 2D materials. Such materials can pave the way for charging ultra-thin electronic devices, self-charging wearable devices, and medical implants. This study systematically explores the thermoelectric attributes of bulk and 2D nanostructured Tin Telluride (SnTe), employing experimental investigations and theoretical analyses based on semiclassical Boltzmann transport theory. The bulk SnTe is synthesized through flame melting, while the 2D SnTe is produced via liquid phase exfoliation. The comprehensive assessment of thermoelectric properties integrated experimental measurements utilizing a Physical Property Measurement System and theoretical calculations from the BoltzTraP code. Experimental thermoelectric studies show a high ZT of 0.17 for 2D SnTe when compared to bulk (0.005) at room temperature. This rise in ZT is due to the high Seebeck coefficient and low thermal conductivity of nanostructured 2D SnTe. Density functional theory (DFT) studies reveal the contribution of the density of states (DOS) and energy bandgap in enhancing the Seebeck coefficient and lowering thermal conductivity by interface scattering., (© 2024 Wiley‐VCH GmbH.)

A vast majority of electrical devices have integrated magnetic units, which generate constant magnetic fields with noticeable vibrations. The majority of existing nanogenerators acquire energy through friction/mechanical forces and most of these instances overlook acoustic vibrations and magnetic fields. Magnetic two-dimensional (2D) tellurides present a wide range of possibilities for devising a potential flexible energy harvester. 2D chromium telluride (2D CrTe 3 ) is synthesized, which exhibits ferromagnetic behavior with a higher T c of ≈224 K. The structure exhibits stable high remnant magnetization, making 2D CrTe 3 a potential material for harvesting magneto-acoustic waves. A magneto-acoustic nanogenerator (MANG) is fabricated and the basic mechanical stability and sensitivity of the device with change in load conditions are tested. A high surface charge density of 2.919 mC m -2 is obtained for the device. The thermal strain created in the lattice structure is examined using in-situ Raman spectroscopy. The magnetic anisotropy energy (MAE) responsible for long-range FM ordering is calculated by theoretical modelling with insights into opening of electronic bandgap which enhances the flexoelectric effects. The MANG can be a potential NG to synergistically tap into the magneto-acoustic vibrations generated from the frequency changes of a vibrating device such as loudspeakers., (© 2024 Wiley‐VCH GmbH.)

Designing efficient and cost-effective materials is pivotal to solving the key scientific and technological challenges at the interface of energy, environment, and sustainability for achieving NetZero. Two-dimensional transition metal dichalcogenides (2D TMDs) represent a unique class of materials that have catered to a myriad of energy conversion and storage (ECS) applications. Their uniqueness arises from their ultra-thin nature, high fractions of atoms residing on surfaces, rich chemical compositions featuring diverse metals and chalcogens, and remarkable tunability across multiple length scales. Specifically, the rich electronic/electrical, optical, and thermal properties of 2D TMDs have been widely exploited for electrochemical energy conversion (e.g., electrocatalytic water splitting), and storage (e.g., anodes in alkali ion batteries and supercapacitors), photocatalysis, photovoltaic devices, and thermoelectric applications. Furthermore, their properties and performances can be greatly boosted by judicious structural and chemical tuning through phase, size, composition, defect, dopant, topological, and heterostructure engineering. The challenge, however, is to design and control such engineering levers, optimally and specifically, to maximize performance outcomes for targeted applications. In this review we discuss, highlight, and provide insights on the significant advancements and ongoing research directions in the design and engineering approaches of 2D TMDs for improving their performance and potential in ECS applications.

Atomically thin two-dimensional (2D) semiconductors have high potential in optoelectronics and magneto-optics appliances due to their tunable band structures and physicochemical stability. The work demonstrates that Gd 3+ incorporated 2D-g-C 3 N 4 nanosheet (Gd 3+ /2D-g-C 3 N 4 NS) is synthesized through chemisorption methodology for defect enrichment. The material characterizations reveal that the ion decoration enhances the surface area and defect concentration of the 2D sheet. The experimental observations have been further corroborated with the help of density functional theory (DFT) simulation. Spin asymmetry polarizations near the Fermi level, obtained through the partial density of states (PDOS) analyses, reveal the magnetic nature of the synthesized material, validating the room temperature ferromagnetism obtained through a vibrating-sample magnetometer (VSM). Gd 3+ /2D-g-C 3 N 4 NS shows significant enhancement in saturation magnetization (Ms) experimentally and computationally compared to the pristine one. The magnetic catalyst shows 98% remediation efficiency for ultrasound-assisted visible-light-driven photodegradation of methyl orange (MO). The synergistic approach of liquid chromatography-mass spectrometry (LC-MS) analyses and DFT studies elucidates reaction intermediates and unveils the degradation mechanism. Post-characterization studies assure the stability of the magnetic catalyst through optical, chemical, magnetic, and microscopic analyses. So, the synthesized material can be proficiently used as a magnetic nanocatalyst in wastewater treatments and spin-electronics applications., (© 2024 Wiley‐VCH GmbH.)

Pesticides are crucial in modern agriculture because they reduce pests and boost yield, but they also represent major risks to human health and the environment; therefore, it is important to monitor their presence in food. Reliable and precise detection techniques are possible ways to address this issue. In this work, we utilize atomically thin (two-dimensional) cobalt telluride (CoTe 2 ) with a high surface area and charge as a template material to detect mancozeb using spectroscopic and electrochemical techniques. When mancozeb (MNZ) molecules interact with 2D CoTe 2 , spectroscopic analyses reveal distinctive spectral shifts that clarify the underlying chemical interactions and binding mechanisms. Furthermore, CoTe 2 's electroactive sites and their manipulation for improved sensitivity and selectivity toward certain MNZ molecules are investigated by electrochemical studies. The CoTe 2 /GCE electrode exhibits enhanced electrochemical activity toward the electrooxidation of MNZ. The developed sensing electrode shows a linear range from 0.184 mM to 18.48 μM and a limit of detection of about 0.18 μM. In addition, we employ density functional theory (DFT) first-principles calculations to validate the experimental findings and comprehend the mechanism behind the interaction between CoTe 2 and MNZ molecules. The study highlights the effectiveness of 2D CoTe 2 as a dual-mode sensing platform for qualitative and quantitative assessment of MNZ pollutants, demonstrated by the integration of electrochemistry and spectroscopy and the critical role that 2D CoTe 2 -based sensors can play in accurate and efficient pesticide detection, which is required for agricultural safety protocols and environmental monitoring.

Schwarzites are porous (spongy-like) carbon allotropes with negative Gaussian curvatures. They are proposed by Mackay and Terrones inspired by the works of the German mathematician Hermann Schwarz on Triply-Periodic Minimal Surfaces (TPMS). This review presents and discusses the history of schwarzites and their place among curved carbon nanomaterials. The main works on schwarzites are summarized and are available in the literature. Their unique structural, electronic, thermal, and mechanical properties are discussed. Although the synthesis of carbon-based schwarzites remains elusive, recent advances in the synthesis of zeolite-templates nanomaterials have brought them closer to reality. Atomic-based models of schwarzites are translated into macroscale ones that are 3D-printed. These 3D-printed models are exploited in many real-world applications, including water remediation and biomedical ones., (© 2024 Wiley‐VCH GmbH.)

Fluorite mineral holds significant importance because of its optoelectronic properties and wide range of applications. Here, we report the successful exfoliation of bulk fluorite ore (calcium fluoride, CaF 2 ) crystals into atomically thin two-dimensional fluoritene (2D CaF 2 ) using a highly scalable liquid-phase exfoliation method. The microscopic and spectroscopy characterizations show the formation of (111) plane-oriented 2D CaF 2 sheets with exfoliation-induced material strain due to bond breaking, leading to the changes in lattice parameter. Its potential role in electrocatalysis is further explored for deeper insight, and a probable mechanism is also discussed. The 2D CaF 2 with long-term stability shows overpotential values of 670 and 770 mV vs RHE for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), respectively, at 10 mA cm -2 . Computational simulations demonstrate the unique "direct-indirect" band gap switching with odd and even numbers of layers. Current work offers new avenues for exploring the structural and electrochemical properties of 2D CaF 2 and its potential applicability.

High entropy materials (HEMs), epitomized by high entropy alloys (HEAs), have sparked immense interest for a range of clean energy and environmental applications due to their remarkable structural versatility and adjustable characteristics. In the face of environmental challenges, HEMs have emerged as valuable tools for addressing issues ranging from wastewater remediation to energy conversion and storage. This review provides a comprehensive exploration of HEMs, spotlighting their catalytic capabilities in diverse redox reactions, such as carbon dioxide reduction to value-added products, degradation of organic pollutants, oxygen reduction, hydrogen evolution, and ammonia decomposition using electrocatalytic and photocatalytic pathways. Additionally, the review highlights HEMs as novel electrode nanomaterials, with the potential to enhance the performance of batteries and supercapacitors. Their unique features, including high capacitance, electrical conductivity, and thermal stability, make them valuable components for meeting crucial energy demands. Furthermore, the review examines challenges and opportunities in advancing HEMs, emphasizing the importance of understanding the underlying mechanisms governing their catalytic and electrochemical behaviors. Essential considerations for optimizing the HEM performance in catalysis and energy storage are outlined to guide future research. Moreover, to provide a comprehensive understanding of the current research landscape, a meticulous bibliometric analysis is presented, offering insights into the trends, focal points, and emerging directions within the realm of HEMs, particularly in addressing environmental concerns.

Industrial emissions, environmental monitoring, and medical fields have put forward huge demands for high-performance and low power consumption sensors. Two-dimensional quasicrystal (2D QC) nanosheets of metallic multicomponent Al 70 Co 10 Fe 5 Ni 10 Cu 5 have emerged as a promising material for gas sensors due to their excellent catalytic and electronic properties. Herein, we demonstrate highly sensitive and selective NO 2 sensors developed by low-cost and scalable fabrication techniques using 2D QC nanosheets and α-Fe 2 O 3 nanoparticles. The sensitivity (Δ R / R %) of the optimal amount of 2D QC nanosheet-loaded α-Fe 2 O 3 sensor was 32%, which is significantly larger about 3.5 times than bare α-Fe 2 O 3 sensors for 1 ppm of NO 2 at 150 °C operating temperature. The sensors exhibited p-type conduction, and resistance was reduced when exposed to NO 2 , an oxidizing gas. The enhanced sensing characteristics are a result of the formation of nanoheterojunctions between 2D QC and α-Fe 2 O 3 , which improved the charge transport and provided a large sensing signal. In addition, the heterojunction sensor demonstrated excellent NO 2 selectivity over other oxidizing and reducing gases. Furthermore, density functional theory calculation examines the adsorption energy and charge transfer between NO 2 molecules on the α-Fe 2 O 3 (110) and QC/α-Fe 2 O 3 (110) heterostructure surfaces, which coincides well with the experimental results.

Atomically thin, few-layered membranes of oxides show unique physical and chemical properties compared to their bulk forms. Manganese oxide (Mn 3 O 4 ) membranes are exfoliated from the naturally occurring mineral Hausmannite and used to make flexible, high-performance nanogenerators (NGs). An enhanced power density in the membrane NG is observed with the best-performing device showing a power density of 7.99 mW m -2 compared to 1.04 µW m -2 in bulk Mn 3 O 4 . A sensitivity of 108 mV kPa -1 for applied forces <10 N in the membrane NG is observed. The improved performance of these NGs is attributed to enhanced flexoelectric response in a few layers of Mn 3 O 4 . Using first-principles calculations, the flexoelectric coefficients of monolayer and bilayer Mn 3 O 4 are found to be 50-100 times larger than other 2D transition metal dichalcogenides (TMDCs). Using a model based on classical beam theory, an increasing activation of the bending mode with decreasing thickness of the oxide membranes is observed, which in turn leads to a large flexoelectric response. As a proof-of-concept, flexible NGs using exfoliated Mn 3 O 4 membranes are made and used in self-powered paper-based devices. This research paves the way for the exploration of few-layered membranes of other centrosymmetric oxides for application as energy harvesters., (© 2023 Wiley‐VCH GmbH.)

Natural materials derived/extracted Ceramics is an excellent material for developing ceramic-based orthopedic implants. Recently, we have demonstrated an easily scalable, energy-efficient green method to extract ceramic particles from bio-waste i.e. chicken bone. Though the chicken bone extract (CBE) has good biocompatibility, it lacks good mechanical properties in the 3D printed condition as that of human bones. Here, we have reinforced CBE with different weight proportions of silicon carbide to improve the mechanical characteristics of the composite. The hybrid of CBE (oxide) and carbide (SiC) is sintered at different temperatures to understand the effect of the interface of the two ceramics. It is observed that temperature has minimal effect and composition has a noticeable effect on mechanical strength as well as bio-toxicity. The toughness (∼3.58 MJ/m 3 ) and compressive strength (∼64.64 MPa) of the 90:10 composition sintered at 1250 °C show the maximum optimum values. A mathematical model has also been developed to predict and correlate the toughness with porosity, volumetric loading, and elastic modulus of the 3D-printed ceramic composite., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Natural ores are abundant, cost-effective, and environmentally friendly. Ultrathin (2D) layers of a naturally abundant van der Waals mineral, Biotite, have been prepared in bulk via exfoliation. We report here that this 2D Biotene material has shown extraordinary Li-Na-ion battery anode properties with ultralong cycling stability. Biotene shows 302 and 141 mAh g -1 first cycle-specific charge capacity for Li- and Na-ion battery applications with ∼90% initial Coulombic efficiency. The electrode exhibits significantly extended cycling stability with ∼75% capacity retention after 4000 cycles even at higher current densities (500-2000 mA g -1 ). Further, density functional theory studies show the possible Li intercalation mechanism between the 2D Biotene layers. Our work brings new directions toward designing the next generation of metal-ion battery anodes.

The use of two-dimensional (2D) layered materials with a noncentrosymmetric structure dramatically increases the potential of nanoscale electromechanical systems and electronic devices. In this work, liquid-phase exfoliation of bulk bismuth titanate was employed to synthesize atomically thin 2D sheets and fabricate a high-performance piezoelectric energy harvester. The structural and morphological properties of the 2D sheets were analyzed, confirming their phase purity and layer formation. Piezoelectric properties of the 2D sheets were evaluated using Piezoresponse Force Microscopy (PFM), demonstrating a high d 33 piezoelectric coefficient of 40 pm/V in a few-layer bismuth titanate nanosheet. A prototype energy harvesting device was fabricated with 2D bismuth titanate as the active material. The piezoelectric response of the fabricated device was recorded at different frequencies and forces, which yielded a maximum d 33 of 57.8 pC/N at 1 Hz. Such a solid electromechanical performance at a relatively infinitesimal input response indicates that 2D bismuth titanate can be useful for piezoelectric energy harvesting applications.

In this work, we decorated piezoresponsive atomically thin ZnO nanosheets on a polymer surface using additive manufacturing (three-dimensional (3D) printing) technology to demonstrate electrical-mechanical coupling phenomena. The output voltage response of the 3D-printed architecture was regulated by varying the external mechanical pressures. Additionally, we have shown energy generation by placing the 3D-printed fabric on the padded shoulder strap of a bag with a load ranging from ∼5 to ∼75 N, taking advantage of the excellent mechanical strength and flexibility of the coated 3D-printed architecture. The ZnO coating layer forms a stable interface between ZnO nanosheets and the fabric, as confirmed by combining density functional theory (DFT) and electrical measurements. This effectively improves the output performance of the 3D-printed fabric by enhancing the charge transfer at the interface. Therefore, the present work can be used to build a new infrastructure for next-generation energy harvesters capable of carrying out several structural and functional responsibilities.

The incessant accumulation of pharmaceutically active compounds (PhACs) in various environmental compartments represents a global menace. Herein, an equimolar high entropy alloy (HEA), i.e., FeCoNiCuZn, is synthesized via a facile and scalable method, and its effectiveness in eliminating four different PhACs from aqueous matrices is rigorously examined. Attributing to its relatively low bandgap and multielement active sites, the as-synthesized quinary HEA demonstrates more pronounced photocatalytic decomposition efficiency, towards tetracycline (86%), sulfamethoxazole (94%), ibuprofen (80%), and diclofenac (99%), than conventional semiconductor-based photocatalysts, under visible light irradiation. Additionally, radical trapping assays are conducted, and the dissociation intermediates are identified, to probe the plausible photocatalytic degradation pathways. Further, the end-products of FeCoNiCuZn-mediated photocatalysis are apparently non-toxic, and the HEA can be successfully recycled repeatedly, with no obvious leaching of heavy metal ions. Overall, the findings of this study testify the applicability of FeCoNiCuZn as a visible light-active photocatalyst, for treating wastewaters contaminated with PhACs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Unique interfacial properties of 2D materials make them more functional than their bulk counterparts in a catalytic application. In the present study, bulk and 2D graphitic carbon nitride nanosheet (bulk g-C 3 N 4 and 2D-g-C 3 N 4 NS) coated cotton fabrics and nickel foam electrode interfaces have been applied for solar light-driven self-cleaning of methyl orange (MO) dye and electrocatalytic oxygen evolution reaction (OER), respectively. Compared to bulk, 2D-g-C 3 N 4 coated interfaces show higher surface roughness (1.094 > 0.803) and enhanced hydrophilicity (θ ∼ 32° < 62° for cotton fabric and θ ∼ 25° < 54° for Ni foam substrate) due to oxygen defect induction as confirmed from morphological (HR-TEM and AFM) and interfacial (XPS) characterizations. The self-remediation efficiencies for blank and bulk/2D-g-C 3 N 4 coated cotton fabrics are estimated through colorimetric absorbance and average intensity changes. The self-cleaning efficiency for 2D-g-C 3 N 4 NS coated cotton fabric is 87%, whereas the blank and bulk-coated fabric show 31% and 52% efficiency. Liquid Chromatography-Mass Spectrometry (LC-MS) analysis determines the reaction intermediates for MO cleaning. 2D-g-C 3 N 4 shows lower overpotential (108 mV) and onset potential (1.30 V) vs. RHE for 10 mA cm -2 OER current density in 0.1 M KOH. Also, the decreased charge transfer resistance (R CT  = 12 Ω) and lower Tafel's slope (24 mV dec -1 ) of 2D-g-C 3 N 4 make it the most efficient OER catalyst over bulk-g-C 3 N 4 and state-of-the-art material RuO 2 . The pseudocapacitance behavior of OER governs the kinetics of electrode-electrolyte interaction through the electrical double layer (EDL) mechanism. The 2D electrocatalyst demonstrates long-term stability (retention ∼94%) and efficacy compared to commercial electrocatalysts., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The efficient monitoring and early detection of viruses may provide essential information about diseases. In this work, we have highlighted the interaction between DNA and a two-dimensional (2D) metal oxide for developing biosensors for further detection of viral infections. Spectroscopic measurements have been used to probe the efficient interactions between single-stranded DNA (ssDNA) and the 2D metal oxide and make them ideal candidates for detecting viral infections. We have also used fully atomistic molecular dynamics (MD) simulation to give a microscopic understanding of the experimentally observed ssDNA-metal oxide interaction. The adsorption of ssDNA on the inorganic surface was found to be driven by favourable enthalpy change, and 5'-guanine was identified as the interacting nucleotide base. Additionally, the in silico assessment of the conformational changes of the ssDNA chain during the adsorption process was also performed in a quantitative manner. Finally, we comment on the practical implications of these developments for sensing that could help design advanced systems for preventing virus-related pandemics.

Radiofrequency (RF) energy harvesting is receiving increased attention in today's digital era due to its potential to replace or improve the longevity of energy storage devices in low-power IoT devices. RF energy is available in the ambient environment, but efficient devices are still not commonly known for RF energy harvesting applications. Here, the main goal is to develop an RF energy harvesting device using multi-layered two-dimensional (2D) galena (PbS). A Schottky diode is fabricated by using 2D galena. RF energy harvesting is demonstrated using a handheld radio transceiver with a carrier frequency of 140-170 MHz. The device extracts RF energy and produces an output DC voltage of a maximum of 1.8 volts and a corresponding output power of 38 mW at 150 MHz, and lights up an LED within a range of 100 cm. At 150 MHz, the device's power conversion efficiency is found to be 19%. DFT calculations support the experimental observations of energy harvesting using 2D galena. The performance results show that 2D galena is a promising material for RF energy harvesting devices.

Direct ink writing (DIW) additive manufacturing is a versatile 3D printing technique for a broad range of materials. DIW can print a variety of materials provided that the ink is well-engineered with appropriate rheological properties. DIW could be an ideal technique in tissue engineering to repair and regenerate deformed or missing organs or tissues, for example, bone and tooth fracture that is a common problem that needs surgeon attention. A critical criterion in tissue engineering is that inserts must be compatible with their surrounding environment. Chemically produced calcium-rich materials are dominant in this application, especially for bone-related applications. These materials may be toxic leading to a rejection by the body that may need secondary surgery to repair. On the other hand, there is an abundance of biowaste building blocks that can be used for grafting with little adverse effect on the body. In this work, we report a bioderived ink made entirely of calcium derived from waste animal bones using a benign process. Calcium nanoparticles are extracted from the bones and the ink prepared by mixing with different biocompatible binders. The ink is used to print scaffolds with controlled porosity that allows better growth of cells. DIW printed parts show better mechanical properties and biocompatibility that are important for the grafting application. Degradation tests and a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay study were done to examine the biocompatibility of the extracted materials. In addition, discrete element modeling and computational fluid dynamics numerical methods are used in Rocky and Ansys software programs. This work shows that biowaste materials if well-engineered can be a never-ending source of raw materials for advanced application in orthopedic grafting.

The development of nanotechnology has been advancing for decades and gained acceleration in the 21st century. Two-dimensional (2D) materials are widely available, giving them a wide range of material platforms for technological study and the advancement of atomic-level applications. The design and application of 2D materials are discussed in this review. In order to evaluate the performance of 2D materials, which might lead to greater applications benefiting the electrical and electronics sectors as well as society, the future paradigm of 2D materials needs to be visualized. The development of 2D hybrid materials with better characteristics that will help industry and society at large is anticipated to result from intensive research in 2D materials. This enhanced evaluation might open new opportunities for the synthesis of 2D materials and the creation of devices that are more effective than traditional ones in various sectors of application., Competing Interests: The authors declare no competing interests., (© 2023 The Authors.)

Developing materials for controlled hydrogen production through water splitting is one of the most promising ways to meet current energy demand. Here, we demonstrate spontaneous and green production of hydrogen at high evolution rate using gadolinium telluride (GdTe) under ambient conditions. The spent materials can be reused after melting, which regain the original activity of the pristine sample. The phase formation and reusability are supported by the thermodynamics calculations. The theoretical calculation reveals ultralow activation energy for hydrogen production using GdTe caused by charge transfer from Te to Gd. Production of highly pure and instantaneous hydrogen by GdTe could accelerate green and sustainable energy conversion technologies., Competing Interests: The authors declare no competing interests., (© 2023.)

For many biomedical applications, high-precision CO 2 detection with a rapid response is essential. Due to the superior surface-active characteristics, 2D materials are particularly crucial for electrochemical sensors. The liquid phase exfoliation method of 2D Co 2 Te 3 production is used to achieve the electrochemical sensing of CO 2 . The Co 2 Te 3 electrode performs better than other CO 2 detectors in terms of linearity, low detection limit, and high sensitivity. The outstanding physical characteristics of the electrocatalyst, including its large specific surface area, quick electron transport, and presence of a surface charge, can be credited for its extraordinary electrocatalytic activity. More importantly, the suggested electrochemical sensor has great repeatability, strong stability, and outstanding selectivity. Additionally, the electrochemical sensor based on Co 2 Te 3 could be used to monitor respiratory alkalosis., Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03497-z., Competing Interests: Conflict of interestThe authors have no conflict of interest., (© The Author(s) 2023.)

Transition-metal tellurides (TMTs) are promising materials for "post-graphene age" nanoelectronics and energy storage applications owing to their industry-standard compatibility, high electron mobility, large spin-orbit coupling (SOC), etc. However, tellurium (Te) having a larger ionic radius ( Z = 52) and broader d-bands endows TMTs with semimetallic nature, restricting their application in photonic and optoelectronic domains. In this work, we report the optical properties of the quantum-confined semiconducting phase of cobalt ditelluride (CoTe 2 ) for the first time, exhibiting excellent two-color band photoabsorption attributes covering the UV-visible and near-infrared regions. Furthermore, novel excitonic resonances (X) of size-varying CoTe 2 nanocrystals and quantum dots (QDs) are indicated by their temperature-dependent emission characteristics, which are attributed to the splitting of band edge states via confinement. On the other hand, the sudden rupture of the large-area CoTe 2 nanosheets via ultrasonication incorporates Co vacancy-mediated localized trap states within the band gap, which is attributed to the superior room-temperature photoluminescence (PL) quantum yield of QDs and further corroborated using Raman analysis and atomistic density functional theory (DFT) simulations. Most interestingly, the excitonic peak of CoTe 2 QDs reveals a unique positive-to-negative thermal quenching transition phenomenon, owing to the thermal activation of nonradiative surface trap states. These results introduce an exciting approach for the defect-mediated color-saturated light emission that paves the way for solution-processed telluride-based QD light-emitting diodes.

We report a previously unreported application of the spatial self-phase modulation (SSPM) technique for recognizing solute-solvent interaction in a suspension of 2D material. Broadband optical absorption of the 2D Co 2 Te 3 leads to a nonlinear optical (NLO) susceptibility for the monolayer, i.e., χ M o n o (3) of 1.5 ×10 -9 (3.3 ×10 -9 ) esu at 532 (632) nm, which is 1-2 orders higher than for the 2D CoTe and CoTe 2 . The fine structure of the SSPM patterns is analyzed to explore the foundations of the observed NLO effects. With increasing polarity of the liquid media, a change of 2D Co 2 Te 3 from homophonous dispersion to aggregation occurs, as confirmed from in situ optical microscopy and UV-vis absorption spectroscopy. As a result, type-I (thickest outer ring) SSPM ring patterns are converted to type-II (thinnest outer ring) SSPM ring patterns. Therefore, using SSPM with a CW laser as an optical tool to identify solvent-polarity-induced aggregation in 2D materials is possible.

Continuous health monitoring through sensitive physiological signals (using a wearable device) is crucial for the early detection of heart diseases and breathing problems. Here, we have developed a flexible hBN/cotton hybrid device that can detect minor signals such as heartbeat and breathed-out air pressure. Systematic observation of the real-time motion sensing showed a peak-to-peak voltage output of ∼1.5 V for each heart rate pulse. The as-fabricated device showed a high voltage output of up to ∼10 V upon applying a pressure of ∼3 MPa. The FTIR results and DFT calculation suggested a chemical interaction between hBN and cellulose, giving rise to flat band characteristics and partially filled σ-bonding (sp 2 ) hybridization. The atomic-scale chemical interface between atomically thin hBN and surface functional groups present on cotton resulted in charge localization and enhanced output voltage. An hBN/cotton hybrid device can bring new insights and opportunities to develop a self-charging and health-monitoring energy-harvesting cloth.

In this work, the synthesis and characterization of ultrathin metal oxide, called biotene, using liquid-phase exfoliation from naturally abundant biotite are demonstrated. The atomically thin biotene is used for energy harvesting using its flexoelectric response under multiple bending. The effective flexoelectric response increases due to the presence of surface charges, and the voltage increases up to ≈8 V, with a high mechano-sensitivity of 0.79 V N -1 for normal force. This flexoelectric response is further validated by density functional theory (DFT) simulations. The atomically thin biotene shows an increased response in the magnetic field and thermal heating. The synthesis of two-dimensional (2D) metal-oxide biotene suggests a wealth of future 2D-oxide material for energy generation and energy harvesting applications., (© 2022 Wiley-VCH GmbH.)

Two-dimensional (2D) materials have been shown to be efficient in energy harvesting. Here, we report the use of waste heat to generate electricity via the combined piezoelectric and triboelectric properties of 2D cobalt telluride (CoTe 2 ). The piezo-triboelectric nanogenerator (PTNG) produced an open-circuit voltage of ∼5 V under 1 N force and the effect of temperature in the range of 305-363 K shows a four-fold energy conversion efficiency improvement. The 2D piezo-tribogenerator shows excellent characteristics with a maximum voltage of ∼10 V, fast response time, and high responsivity. Density functional theory was used to gain further insights and validation of the experimental results. Our results could lead to energy harvesting approaches using 2D materials from various thermal sources and dissipating waste heat from electronic devices.

A giant enhancement of nearly 100 times is seen in triethylamine response through Ti-Zr-Cr-V-Ni high-entropy alloy nanoparticle (HEA NP)-induced fermi energy control of two-dimensional molybdenum disulfide (MoS 2 ) nanosheets. These Laves-phase HEA NP-decorated MoS 2 samples are synthesized using cryomilling followed by 30 h of sonication. The prolonged sonication results in well-exfoliated MoS 2 with fairly small (∼10-20 nm) HEA NPs anchored due to cryomilling confirmed by extensive microscopic and spectroscopic examinations. The presence of HEA NPs leads to reduction in edge oxidation of MoS 2 as seen from X-ray photoelectron spectroscopy. Moreover, this edge state reduction causes strong Fermi level pinning, which is commonly observed in layered MoS 2 with bulk metal electrodes. This leads to target gas-specific carrier-type response and selective oxidation of TEA vapors due to highly catalytically active metals. The resulting composite (MoS 2 + NPs) exhibits high response (380% for 2000 ppm TEA vapors) along with selectivity toward TEA at 50 °C. The cross-sensitivity of the composite to other volatile organic compounds and NH 3 , CO, and H 2 has been very minimal. Thus, the highly selective catalytic activity of metal alloy NPs and their Fermi energy control has been proposed as the prime factors for observed large sensitivity and selective response of MoS 2 + NP nanocomposites.

Lithium ion hybrid capacitors (LIHCs) have a capacitor-type cathode and a battery-type anode and are a prospective energy storage device that delivers high energy/power density. However, the kinetic imbalance between the cathode and the anode is a key obstacle to their further development and application. Herein, we prepared TiNb 2 O 7 nanoparticles through a facile solvothermal method and annealing treatment. Then a homogeneous three-dimensional (3D) self-supported reduced graphene oxide (rGO)-coated TiNb 2 O 7 (TiNb 2 O 7 /rGO) nanocomposite was constructed by freeze-drying, followed by a high-temperature reduction, which demonstrates an enhanced pseudocapacitive lithium ions storage performance. Benefiting from the improved electrical conductivity, ultrashort ions diffusion paths, and 3D architecture, the TiNb 2 O 7 /rGO nanocomposite exhibits a high specific capacity of 285.0 mA h g -1 , excellent rate capability (73.6% capacity retention at 8 A g -1 ), and superior cycling stability. More importantly, quantitative kinetics analysis reflects that the capacity of TiNb 2 O 7 /rGO is mainly dominated by capacitive behavior, making it perfectly match with the capacitor-type activated carbon (AC) cathode. By using pre-lithiated TiNb 2 O 7 /rGO as anode material and AC as cathode material, a high-rate TiNb 2 O 7 /rGO//AC LIHC device can be fabricated, which delivers an ultrahigh energy density of 127 Wh kg -1 at the power density of 200 W kg -1 , a maximum power density of 10 kW kg -1 at the energy density of 56.4 Wh kg -1 , and durable service life., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Atomically thin two-dimensional (2D) transition metal dichalcogenides (TMDCs) have attracted significant attention owing to their prosperity in material research. The inimitable features of TMDCs triggered the emerging applications in diverse areas. In this review, we focus on the tailored and engineering of the crystal lattice of TMDCs that finally enhance the efficiency of the material properties. We highlight several preparation techniques and recent advancements in compositional engineering of TMDCs structure. We summarize different approaches for TMDCs such as doping and alloying with different materials, alloying with other 2D metals, and scrutinize the technological potential of these methods. Beyond that, we also highlight the recent significant advancement in preparing 2D quasicrystals and alloying the 2D TMDCs with MAX phases. Finally, we highlight the future perspectives for crystal engineering in TMDC materials for structure stability, machine learning concept marge with materials, and their emerging applications., Competing Interests: The authors declare no competing or financial interests., (© 2021 The Author(s).)