Nanomaterials (NMs) have gained tremendous attention in various applications in the modern era. The most significant challenge associated with NMs is their strong propensity to aggregate. The chemical surface modification of NMs has garnered notable attention in managing NM dispersion and aggregation. Among the modification approaches, the silane modification of NMs has generated great interest among researchers as a versatile approach to tailoring the surface characteristics of NMs. This review comprehensively examined the recent advancements in silane modification techniques with a focus on triboelectric nanogenerator (TENG) applications. It provides an overview of silane chemistry and its interaction with diverse NMs, elucidating the underlying mechanisms governing the successful surface functionalization process. This review emphasized the silane modification, such as improved mechanical properties of composites, enhanced electrical and thermal conductivity, functional coatings, water treatment, textile industries, catalysis, membrane applications, and biomedical applications, of various NMs. In particular, the role of silane-modified NMs in advancing energy harvesting technologies was highlighted, showcasing their potential to enhance the performance and stability of next-generation devices.

Since the last decade, hyperbranched polymers (HBPs) have gained wider theoretical interest and practical applications in sensor technology due to their ease of synthesis, highly branched structure but dimensions within nanoscale, a larger number of modified terminal groups and lowering of viscosity in polymer blends even at higher HBP concentrations. Many researchers have reported the synthesis of HBPs using different organic-based core-shell moieties. Interestingly, silanes, as organic-inorganic hybrid modifiers of HBP, are of great interest as they resulted in a tremendous improvement in HBP properties like increasing thermal, mechanical and electrical properties compared to that of organic-only moieties. This review focuses on the research progress in organofunctional silanes, silane-based HBPs and their applications since the last decade. The effect of silane type, its bi-functional nature, its influence on the final HBP structure and the resultant properties are covered in detail. Methods to enhance the HBP properties and challenges that need to be overcome in the near future are also discussed.

This study investigates the potential of zinc oxide (ZnO) and Ag-doped zinc oxide (Ag-ZnO) nanoparticles (NPs) (1, 3 and 5 wt%) electrospun into poly(vinylidene fluoride) (PVDF) based triboelectric nanogenerators (TENGs) to harness electrical energy from ambient mechanical vibrations. ZnO and Ag-ZnO NPs were developed using a co-precipitation method. 3 wt% Ag-ZnO doping was optimized to exhibit a higher β-crystalline phase in PVDF (PAZ3). The electrospun ZnO and Ag-ZnO loaded PVDF nanofiber mats (NFMs) served as tribo-negative layer, while thermoplastic polyurethane (TPU) served as tribo-positive layer in the TENG device fabrication. The electrical measurement results revealed that pristine PVDF/TPU-based TENG device exhibited lower performance (V _oc = 9.0 V and I _sc = 0.6 µA) compared to the optimized PAZ3/TPU-based TENG (V _oc = 51 V and I _sc = 1.2 µA), and utilized for concurrent applications such as powering over 10 light-emitting diodes, energy harvesting and healthcare monitoring applications. Overall, the study not only reveals the significant potential of PAZ3/TPU-based TENG for excellent output performance, but also provides a new insight into next-generation clean, affordable and sustainable energy harvesting materials.

A flexible and portable triboelectric nanogenerator (TENG) based on electrospun polyvinylidene fluoride (PVDF) doped with copper oxide (CuO) nanoparticles (NPs, 2, 4, 6, 8, and 10 wt.-% w.r.t. PVDF content) was fabricated. The structural and crystalline properties of the as-prepared PVDF-CuO composite membranes were characterized using SEM, FTIR, and XRD. To fabricate the TENG device, the PVDF-CuO was considered a tribo-negative film and the polyurethane (PU) a counter-positive film. The output voltage of the TENG was analyzed using a custom-made dynamic pressure setup, under a constant load of 1.0 kgf and 1.0 Hz frequency. The neat PVDF/PU showed only 1.7 V, which further increased up to 7.5 V when increasing the CuO contents from 2 to 8 wt.-%. A decrease in output voltage to 3.9 V was observed for 10 wt.-% CuO. Based on the above results, further measurements were carried out using the optimal sample (8 wt.-% CuO). Its output voltage performance was evaluated as a function of varying load (1 to 3 kgf) and frequency (0.1 to 1.0 Hz) conditions. Finally, the optimized device was demonstrated in real-time wearable sensor applications, such as human motion and health-monitoring applications (respiration and heart rate).