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Highlights High‐density polyethylene (HDPE) nanocomposites containing different optimized fractions of carbon nanofiber (CNF) at 6 wt.%, polyethylene glycol (PEG) at 4 wt.%, and copper oxide (CuO) nanorods in concentration ranges of 0.15, 0.5, and 2 wt.% were successfully melt processed using corotating twin extrusion and compression molding technique. The effect of PEG and CuO nanofiller on the HDPE matrix were studied, particularly for the percolation threshold for electrical conductivity, structural morphology, and other properties including thermal stability, thermal conductivity (TC), dielectric, and UV protection properties. It is observed that PEG acts as a good compatibilizer, facilitating better interfacial connection between CNF and HDPE matrix. The optimized composite with 0.15 wt.% CuO nanorods (H/C6/P4/Cu0.15) shows a fine morphology and strong interfacial connections between fillers and the matrix, as observed in FE‐SEM micrographs. This optimized composite exhibits improved thermal stability, higher thermal conductivity (0.0404 W.K−1.m−1), increased dielectric constant, reduced electrical volume resistivity (from 2.1 × 1015 to 2.1 × 106 Ω.cm), and lower optical band gap value (2.74 eV). Additionally, all prepared nanocomposites offer approximately 100% Ultraviolet Protection Factor (UPF) rating for UV protection. The transformation of insulating HDPE into conducting HDPE composites. The effect of CuO nanorods was investigated in compatibilized HDPE composites. A percolation is achieved in the HDPE composite at 0.15 wt.% of CuO nanorods. PEG and CuO nanorods improved the multifunctional properties of the composite. [ABSTRACT FROM AUTHOR]

Recently, Bi 2 S 3 has garnered significant interest in the thermoelectric field due to its abundant and low-toxicity constituents. Nevertheless, pure Bi 2 S 3 material has not been utilized in thermoelectric applications because of its low electrical conductivity. This study presents the fabrication of the Bi 0.33 (Bi 6 S 9)Br-doped Bi 2 S 3 bulk samples with high electrical conductivity and mechanical performance via the melting method in conjunction with spark plasma sintering technology. The increased electron concentration is attributed to the replacement of S2− by Br− and the introduction of extra Bi in the lattice. At 323 K, the electrical conductivity of the Bi 2 S 3 + 3 wt% Bi 0.33 (Bi 6 S 9)Br sample increased to 208 Scm−1, signifying a 3-order-of-magnitude enhancement compared to the pure sample. The enhanced electrical conductivity led to the optimization of the electrical transport properties. At 573 K, the Bi 2 S 3 + 2 wt% Bi 0.33 (Bi 6 S 9)Br bulk sample achieved a peak power factor value of 481 μWm−1K−2, which is four times higher than that of the pure sample. Notably, the low lattice thermal conductivity of the Bi 2 S 3 + 5 wt% Bi 0.33 (Bi 6 S 9)Br sample was 0.56 W−1 m−1K−1 at 673 K. Given the significantly enhanced electrical transport properties and suppressed thermal conductivity, the Bi 2 S 3 + 2 wt% Bi 0.33 (Bi 6 S 9)Br sample achieved a peak ZT value of 0.45 at 673 K and a high ZT ave value of 0.33 from 373 to 673 K. Compared to the pure Bi 2 S 3 sample, these values are 5 times and 3 times higher, respectively. Such advancements can be implemented in the domain of power generation. Additionally, the mechanical properties of the sample exhibited substantial enhancement, and the average hardness of the 2 wt% Bi 0.33 (Bi 6 S 9)Br-doped sample increased from 2.73 GPa of the pure sample to 3.03 GPa. This novel strategy of dual point defects modulation provides a new pathway to enhance the thermoelectric performance of Bi 2 S 3 and other material systems. [Display omitted] • The Bi 0.33 (Bi 6 S 9)Br doped Bi 2 S 3 bulk samples are fabricated by solid states reaction combined with the SPS technology. • A high power factor (481 μW m−1 K−1) were obtained at 573 K. • The mechanical properties of the doped sample showed significant improvement. • A peak ZT value of∼0.45 at 673 K and ZT ave value of∼0.33 from 373 to 673 K were obtained. [ABSTRACT FROM AUTHOR]

[Display omitted] • Gold nanorods were synthesized using hydroquinone (HQ) and ascorbic acid (AA). • Ascorbic acid-reduced gelatin-coated gold nanorods are more thermally stable. • A high gelatin volume ratio affects the photothermal response of the gold nanorods. • Ascorbic acid-reduced gelatin-coated gold nanorods gave a better photothermal response. The development of Gold nanorods (AuNRs) as phototherapeutic agents (PTAs) has attracted much interest from researchers in recent decades. The majority of their synthetic methods use Hydroquinone (HQ) and Ascorbic acid (AA) as the reducing agent, and these have been shown to affect the properties of AuNRs. However, no study has been conducted on how these two reducing reagents can affect their application, especially after coating. Therefore, we herein report a seed-mediated synthesis of AuNRs using two reducing agents and coating them with gelatin at different volume ratios (1:5, 1:2, 1:1,2:1, and 5:1). The HQ-reduced AuNRs and AA-reduced AuNRs absorbed at TSPR of 512 nm and 514 nm and LSPR of 914 nm and 847 nm, respectively. The gelatin-coated HQ-reduced and AA-reduced AuNRs did not show significant LSPR wavelength changes for all the volume ratios. However, a slight increase in the TSPR and the absorbance at regions below 550 nm was seen for volume ratios 1:1, 2:1, and 5:1. The thermal stability studies at 70 ℃ for the coated materials revealed that AA-reduced AuNRs were more thermally stable than HQ-reduced AuNRs, with the less optical shift. The coated AA-reduced AuNRs were further tested for photothermal responses. The results show that the high gelatin volume during coating affects the photothermal response of the AuNRs. This study indicates volume ratio of 1:5 and 1:2 has good stability while maintaining the good photothermal profiling needed in PTT applications. Hence Gel@AuNRs synthesised with AA is an excellent PTT agent for phototherapy applications. [ABSTRACT FROM AUTHOR]