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The current global warming, coupled with the growing demand for energy in our daily lives, necessitates the development of more efficient and reliable energy storage devices. Lithium batteries (LBs) are at the forefront of emerging power sources addressing these challenges. Recent studies have shown that integrating hexagonal boron nitride (h‐BN) nanomaterials into LBs enhances the safety, longevity, and electrochemical performance of all LB components, including electrodes, electrolytes, and separators, thereby suggesting their potential value in advancing eco‐friendly energy solutions. This review provides an overview of the most recent applications of h‐BN nanomaterials in LBs. It begins with an informative introduction to h‐BN nanomaterials and their relevant properties in the context of LB applications. Subsequently, it addresses the challenges posed by h‐BN and discusses existing strategies to overcome these limitations, offering valuable insights into the potential of BN nanomaterials. The review then proceeds to outline the functions of h‐BN in LB components, emphasizing the molecular‐level mechanisms responsible for performance improvements. Finally, the review concludes by presenting the current challenges and prospects of integrating h‐BN nanomaterials into battery research. [ABSTRACT FROM AUTHOR]

The demand for sustainable power sources for wearable electronic devices has spurred exploration into novel energy harvesting technologies. Among these, flexible thermoelectric (TE) materials and generators (TEGs) show promise for transforming body heat into electrical power. For this purpose, organic and polymeric semiconducting materials, such as poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), have been at the forefront of research recently due to their flexibility, nontoxicity, easy processability, high electrical conductivity, and low thermal conductivity. However, hybridization with inorganic materials, optimization of doping levels, and structural modifications to enhance their TE conversion efficiency are still ongoing areas of investigation, and a comprehensive study encompassing all these approaches is lacking. This research presents the first comprehensive and encyclopedic study of the TE properties of PEDOT:PSS thin films hybridized with Bi0.5Sb1.5Te3 particles to explore the relationship between particle size/concentration, chemical post-treatment strategies, and the resulting microstructural, morphological, and TE properties. Initially, PEDOT:PSS was hybridized with Bi0.5Sb1.5Te3 particles with a wide range of size (0.3–1.4 μm) and concentration (5–60 wt%), and the microstructure and TE properties of the resulting composite films were systematically studied. The composite with 40 wt% Bi0.5Sb1.5Te3 particles exhibited the highest power factor at room temperature, was chosen as the optimal sample, and underwent various single and sequential chemical post-treatments using secondary dopants (DMSO, EG, H2SO4) and a dedoping agent (NaOH). While single post-treatment with 0.5 M H2SO4 could increase the power factor up to 240 times compared to the pristine composite, a sequential pos-treatment with 0.5 M H2SO4 and 0.1 M NaOH resulted in an 864-fold increase in the power factor at room temperature. Furthermore, the temperature-dependent electrical conductivity and Seebeck coefficient of the composite thin films were explored in each case (between 300 K and 375 K) to determine the dominant charge transport mechanism. It was revealed that the charge carrier transport mechanism was three-dimensional variable range hopping in pristine composite samples; however, metallic conduction was observed in the samples after sequential chemical post-treatment. The findings of this paper make it a thorough reference for understanding the TE properties of inorganic/polymeric composites, and offer a detailed perspective on strategies to optimize their power factor for applications in flexible TEGs. [ABSTRACT FROM AUTHOR]

BiSbTe‐based nanocomposites hybridized with ceramic nanoparticles have recently revealed their higher efficiency as thermoelectric materials for near room‐temperature applications, as compared to the traditional BiTe‐SbTe alloys. Herein, the incorporation of ultra‐small Bi nanoprecipitates into the microstructure of a Bi0.5Sb1.5Te3/Sb2O3 nanocomposite and the consequential effects on the thermal and electrical transport properties of this three‐phase hybrid system is reported. Electron microscopy characterization and systematic analysis of the thermoelectric properties of Bi0.5Sb1.5Te3/Sb2O3/Bi nanoprecipitate samples suggest that the minute Bi nanoprecipitates increase the charge carrier concentration of the nanocomposites, act as effective scattering sites throughout the microstructure, and shift the maximum Seebeck coefficient values to higher temperatures. [ABSTRACT FROM AUTHOR]

Nanoengineering of thermoelectric (TE) materials is an effective approach to decouple their electronic and thermal transport properties, hence enhancing their TE efficiency. Nanoengineering strategies can significantly reduce the thermal conductivity through the corporation of different phonon scattering mechanisms, whereas the electrical conductivity may not be affected considerably. Herein, the effects of three nanoengineering approaches on the structural, electrical, and thermal properties of Bi0.5Sb1.5Te3 (BST) alloy are compared: (a) nanohybridization of the alloy by adding Sb2O3 nanoparticles, (b) severe plastic deformation via high‐pressure torsion, and (c) grain refinement by sonication of BST powders before sintering. It is shown that among these methods, severe plastic deformation induces ultrafine grains and a high density of dislocations, resulting in a large reduction of the total thermal conductivity (32.8%) and a moderate decline in the electrical conductivity of (15.7%) at 300 K. A notable decrease in the lattice thermal conductivity (56.8% at 300 K) is attributed to midfrequency phonon scattering by the dislocations together with low and high frequency scatterings through grain boundaries and point defects, respectively. A new pathway is opened for designing highly efficient TE materials through nanoengineering approaches, particularly severe plastic deformation. [ABSTRACT FROM AUTHOR]

Cellulose nanocrystals (CNCs), a sustainable nanomaterial, are in situ incorporated into emulsion‐based pressure‐sensitive adhesives (PSAs). Commercially available CNCs with different surface hydrophilicity and surface charge (CNC101 and CNC103 from CelluForce) are used to explore their role in PSA property modification. Viscosity measurements and atomic force microscopy reveal differences in degree of association between the CNCs and the latex particles depending on the surface properties of the CNCs. The more hydrophilic and higher surface charge CNCs (CNC101) show less association with the latex particles. Dynamic strain sweep tests are used to analyze the strain‐softening of the nanocomposites based on CNC type and loading. The CNC101 nanocomposites soften at lower strains than their CNC103 counterparts. This behavior is confirmed via dynamic frequency tests and modeling of the nanocomposites' storage moduli, which suggest the formation of CNC aggregates of, on average, 3.8 CNC101 and 1.3 CNC103 nanoparticles. Finally, PSA properties, i.e., tack, peel strength, and shear strength, simultaneously increase upon addition of both CNC types, although to different extents. The relationship between the PSA properties and CNC surface properties confirms that the less hydrophilic CNCs lead to improved CNC dispersion in the PSA films and therefore, enhance PSA properties. [ABSTRACT FROM AUTHOR]

Polymers are a class of materials that provide unparalleled benefits to humanity, fulfilling countless needs in an exceedingly broad range of applications. Because of their ubiquity and current ways of producing them, polymers also pose significant challenges to the environment. Inspired by a previous publication on sustainable polymer reaction engineering, an update is provided on the latest trends in the use of renewable starting materials for polymers, efforts in process intensification and water‐based polymerization, as well as approaches to dealing with the end of the polymers' application life. We seek to answer the question about how far along we are regarding the achievement of completely sustainable polymer processes. [ABSTRACT FROM AUTHOR]