The future photovoltaic technologies based on perovskite materials are aimed to build low tech, truly economical, easily fabricated, broadly deployable, and trustworthy solar cells. Hole transport material (HTM) free perovskite solar cells (PSCs) are among the most likely architectures which hold a distinctive design and provide a simple way to produce large-area and cost-effective manufacture of PSCs. Notably, in the monolithic scheme of the HTM-free PSCs, all layers can be printed using highly reproducible and morphology-controlled methods, and this design has successfully been demonstrated for industrial-scale fabrication. In this review article, we comprehensively describe the recent advancements in the different types of mesoporous (nanostructured) and planar HTM-free PSCs. In addition, the effect of various nanostructures and mesoporous layers on their performance is discussed using the electrochemical impedance spectroscopy (EIS) technique. We bring together the different perspectives that researchers have developed to interpret and analyze the EIS data of the HTM-free PSCs. Their analysis using the EIS tool, the limitations of these studies, and the future work directions to overcome these limitations to enhance the performance of HTM-free PSCs are comprehensively considered.

The electrospinning technique has been successfully used to prepared micro-fibers of the poly(lactic acid)/polyaniline–zinc oxide (PLA/PANI–ZnO) composite. The polyaniline–zinc oxide (PANI–ZnO) nanocomposites are synthesized by hydrothermal and in situ polymerization methods. X-ray diffraction techniques are used to study the structural properties of the PLA/PANI–ZnO composite fibers and the PANI–ZnO nanocomposite. The average crystallite size of the PANI–ZnO nanocomposite is found to be 36 nm. The morphology and diameter of the composite fibers are analyzed by scanning electron microscopy (SEM). The average fiber diameter of the pure poly(lactic acid) (PLA) fiber is around 2.5 μm and that of the PLA/PANI–ZnO composite fiber is around 1.4 μm. Differential scanning calorimetry (DSC) provides the thermal properties of the PLA/PANI–ZnO composite fibers. The melting temperature (T_m) for the pure PLA is observed at 149.3 °C, and it is shifted to 153.0 °C for the PLA/PANI–ZnO composite fibers. The enhanced thermal properties of the composite fibers are due to the interaction between the polymer and the nanoparticles. The water contact angle measurements probe the surface hydrophilicity of the PLA/PANI–ZnO composite fibers. The role of the PANI–ZnO nanocomposite on the sensing behavior of PLA fibers has also been investigated. The humidity sensing properties of the composite fiber based sensor are studied in the relative humidity (RH) range of 20–90% RH. The experimental results show that the composite fiber exhibited good response (85 s) and recovery (120 s) times. These results indicate that the one-dimensional (1D) fiber structure enhances the humidity sensing properties.

Nanomedicine, a convergence of nanotechnology and medical sciences, has unleashed transformative potential in healthcare. However, harnessing the benefits of nanomedicine requires a thorough understanding of its regulatory landscape. An in-depth discussion of regulatory considerations, including molecular safety assessment, harmonization of the regulatory landscape, and shaping the future of innovation, is presented in this discourse. The molecular safety assessment entails evaluating interactions between nanoparticles and biomolecules, ensuring compatibility at the molecular level. Harmonization involves developing international standards and guidelines for a consistent regulatory approach, while shaping innovations emphasizes integrating molecular safety assessments into early stages of development. Challenges encompass the need for standardized assessment methods, balancing innovation with safety, and addressing unique features of novel molecular designs. As the nanomedicine landscape evolves, effective regulatory strategies must navigate the intricate interplay of molecules and technologies, ensuring both patient access and product safety.

A flexible thin membrane made of a graphene–PANI nanocomposite decorated PS electrospun fibre as a highly sensitive carbon dioxide gas sensor.

The integration of immunotoxicity data into chemical risk assessment paradigms is essential for comprehensively evaluating the potential health hazards posed by chemical exposures. This review provides a comprehensive overview of the methodologies, challenges, and future directions for integrating immunotoxicity data into risk assessment frameworks. It discusses the fundamental principles of immunotoxicology and its relevance to chemical risk assessment, highlighting the critical roles of the immune system in health and defense against harmful agents. Next, we explore traditional chemical risk assessment frameworks, including exposure assessment, hazard identification, dose–response assessment, and risk characterization, highlighting the need for incorporating immunotoxicity endpoints to enhance hazard characterization and risk estimation. Subsequently, we delve into dose–response modelling for immunotoxicity, elucidating principles, methods, and case studies illustrating dose–response relationships and extrapolation of data from animal studies to humans. Furthermore, we discuss hazard characterization of immunotoxicity, focusing on the identification of immunotoxic hazards, evaluation of immunotoxicity endpoints, and utilization of immunological biomarkers in risk assessment. We then examine cumulative risk assessment strategies, presenting a conceptual framework for assessing cumulative risks of immunotoxicity from multiple chemical exposures and methods for integrating exposure and hazard data from different chemicals. Lastly, we explore emerging trends and future directions in immunotoxicity risk assessment, including high-throughput screening assays, omics technologies, computational modelling, and alternative testing methods, along with potential regulatory implications and future research needs. This review provides valuable insights for researchers, regulators, and stakeholders involved in chemical risk assessment and public health protection, facilitating the development of evidence-based strategies for safeguarding human health from immunotoxic risks associated with chemical exposures.