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1. Uncovering the Formation Mechanism of Hexagonal Porous MXene

   https://doi.org/10.1093/mam/ozaf048.935  

   Cheng, Yongfa; Koo, Kunmo; Cai, Zizhen; Hu, Xiaobing; Dravid, Vinayak P (July 2025, Microscopy and Microanalysis)

   2D nanomaterials have garnered significant attention due to their unique physicochemical properties. MXene, a type of twodimensional transition metal carbide, nitride, or carbonitride, has become a focal point in materials science due to its excellent metallic conductivity, tunable chemical functional groups, outstanding mechanical properties, and unique surface chemistry [1,2]. Compared to traditional metal oxides, MXenes exhibit superior mechanical strength and flexibility, making them ideal candidates for high-performance energy storage devices (such as lithium-ion batteries and supercapacitors) as well as flexible electronic devices [3]. However, there are still some limitations, such as the self-stacking phenomenon, which restricts the improvement of its performance. Researchers have gradually expanded various types of MXene structures, enhancing their value in fields such as energy, electronics, sensing, nanofluids, computing, and the environment by tuning the element composition, surface functional groups, interlayer structure, and composite structure design [4,5]. 

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2. Critical Review on Nanomaterials for Enhancing Bioconversion and Bioremediation of Agricultural Wastes and Wastewater

   https://doi.org/10.3390/en15155387  

   Salehi, Bahare; Wang, Lijun (August 2022, Energies)

   Anaerobic digestion (AD), microalgae cultivation, and microbial fuel cells (MFCs) are the major biological processes to convert organic solid wastes and wastewater in the agricultural industry into biofuels, biopower, various biochemical and fertilizer products, and meanwhile, recycle water. Various nanomaterials including nano zero valent irons (nZVIs), metal oxide nanoparticles (NPs), carbon-based and multicompound nanomaterials have been studied to improve the economics and environmental sustainability of those biological processes by increasing their conversion efficiency and the quality of products, and minimizing the negative impacts of hazardous materials in the wastes. This review article presented the structures, functionalities and applications of various nanomaterials that have been studied to improve the performance of AD, microalgae cultivation, and MFCs for recycling and valorizing agricultural solid wastes and wastewater. The review also discussed the methods that have been studied to improve the performance of those nanomaterials for their applications in those biological processes. 

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3. Liquid metal nanocomposites

   https://doi.org/10.1039/d0na00148a  

   Malakooti, Mohammad H.; Bockstaller, Michael R.; Matyjaszewski, Krzysztof; Majidi, Carmel (July 2020, Nanoscale Advances)

   Liquid metal (LM) has attracted tremendous interest over the past decade for its enabling combination of high electrical and thermal conductivity and low mechanical compliance and viscosity. Efforts to harness LM in electronics, robotics, and biomedical applications have largely involved methods to encapsulate the liquid so that it can support functionality without leaking or smearing. In recent years, there has been increasing interest in LM “nanocomposites” in which either liquid metal is mixed with metallic nanoparticles or nanoscale droplets of liquid metal are suspended within a soft polymer matrix. Both of these material systems represent an important step towards utilizing liquid metal for breakthrough applications. In this minireview, we present a brief overview of recent progress over the past few years in methods to synthesize LM nanomaterials and utilize them as transducers for sensing, actuation, and energy harvesting. In particular, we focus on techniques for stable synthesis of LM nanodroplets, suspension of nanodroplets within various matrix materials, and methods for incorporating metallic nanoparticles within an LM matrix. 

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4. Wafer-scale 2D PtTe ₂ layers for high-efficiency mechanically flexible electro-thermal smart window applications

   https://doi.org/10.1039/D0NR01845G  

   Okogbue, Emmanuel; Ko, Tae-Jun; Han, Sang Sub; Shawkat, Mashiyat Sumaiya; Wang, Mengjing; Chung, Hee-Suk; Oh, Kyu Hwan; Jung, Yeonwoong (May 2020, Nanoscale)

   null (Ed.)

   Two-dimensional (2D) transition metal dichalcogenide (TMD) layers have gained increasing attention for a variety of emerging electrical, thermal, and optical applications. Recently developed metallic 2D TMD layers have been projected to exhibit unique attributes unattainable in their semiconducting counterparts; e.g. , much higher electrical and thermal conductivities coupled with mechanical flexibility. In this work, we explored 2D platinum ditelluride (2D PtTe 2 ) layers – a relatively new class of metallic 2D TMDs – by studying their previously unexplored electro-thermal properties for unconventional window applications. We prepared wafer-scale 2D PtTe 2 layer-coated optically transparent and mechanically flexible willow glasses via a thermally-assisted tellurization of Pt films at a low temperature of 400 °C. The 2D PtTe 2 layer-coated windows exhibited a thickness-dependent optical transparency and electrical conductivity of >10 6 S m −1 – higher than most of the previously explored 2D TMDs. Upon the application of electrical bias, these windows displayed a significant increase in temperature driven by Joule heating as confirmed by the infrared (IR) imaging characterization. Such superior electro-thermal conversion efficiencies inherent to 2D PtTe 2 layers were utilized to demonstrate various applications, including thermochromic displays and electrically-driven defogging windows accompanying mechanical flexibility. Comparisons of these performances confirm the superiority of the wafer-scale 2D PtTe 2 layers over other nanomaterials explored for such applications. 

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5. Controlling processing temperatures and self-limiting behaviour in intense pulsed sintering by tailoring nanomaterial shape distribution

   https://doi.org/10.1039/C7RA11013H  

   Dexter, M.; Bhandari, R.; Chang, C-H.; Malhotra, R. (January 2017, RSC Advances)

   Intense Pulsed Light Sintering (IPL) uses pulsed, large-area, broad-spectrum visible light from a xenon lamp for rapid fusion of nanomaterials into films or patterns used in flexible sensors, solar cells, displays and other applications. Past work on the IPL of silver nanoparticles has shown that a self-damping coupling between densification and optical absorption governs the evolution of the deposited nanomaterial temperature during IPL. This work examines the influence of the nanomaterial shape distribution on this coupling and on the temperature evolution in IPL of silver nanowire–nanoparticle composite films. The film thickness, resistivity, micromorphology, crystallinity and optical properties are compared for varying ratios of nanowire to nanoparticle content in the film. It is shown for the first time, that increasing the nanowire content reduces the maximum film temperature during IPL from 240 °C to 150 °C and substantially alters the temperature evolution trends over consecutive pulses, while enabling film resistivity within 4–5 times that of bulk silver in 2.5 seconds of processing time. Nanoscale electromagnetic models are used to understand optical absorption as a function of changing ratio of nanowires to nanoparticles in a model assembly that emulates the IPL experiments performed here. The coupling between densification and optical absorption is found to inherently depend on the nanomaterial shape distribution and the ability of this phenomenon to explain the experimental temperature evolution trends is discussed. The implications of these observations for controlling self-damping coupling in IPL and the optimum nanoparticle to nanowire ratios for concurrently achieving high throughput, low processing temperatures, low material costs and low resistivity in IPL of conductive metallic nanomaterials are also described. 

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