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Synthesis of silver nanoparticles–chitosan composite particles sphere (AgNPs-chi-spheres) has been completed and its characterization was fulfilled by UV–vis spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and zetasizer nano. UV–vis spectroscopy characterization showed that AgNPs-chi-spheres gave optimum absorption at a wavelength of 410 nm. The XRD spectra showed that the structure of AgNPs-chi-spheres were crystalline and spherical. Characterization by SEM showed that AgNPs-chi-spheres, with the addition of 20% of NaOH, resulted in the lowest average particle sizes of 46.91 nm. EDX analysis also showed that AgNPs-chi-spheres, with the addition of a 20% NaOH concentration, produced particles with regular spheres, a smooth and relatively nonporous structure. The analysis using zetasizer nano showed that the zeta potential value and the polydispersity index value of the AgNPs-chi-sphere tended to increase with an increased NaOH concentration. The results of the microbial activity screening showed that the AgNP-chi-Spheres with highest concentration of NaOH, produced the highest inhibition zone diameters against S. aureus, E. coli, and C. albicans, with inhibition zone diameters of 19.5, 18.56, and 12.25 nm, respectively.

Although energy is a necessary component of production and hence a contaminant, the environmental effect varies depending on the type of energy used. Renewable sources of energy can provide ecological advantages, particularly when contrasted with fossil fuels, which emit high levels of CO2 emissions. Thus, the research explores the impact of eco-innovation (ECO), green energy (REC), and globalization (GLOB) on the ecological footprint (ECF) in the BRICS nations using the panel nonlinear autoregressive distributed lag (PNARDL) technique between 1990 and 2018. The empirical results indicate that there is cointegration in the model. The results from the PNARDL show that a positive shift in renewable energy, eco-innovation, and globalization decreases the ecological footprint, while positive (negative) shifts in non-renewable energy and economic growth intensify the ecological footprint. The paper suggests several policy recommendations based on these results., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

This paper investigates the role of nuclear energy in promoting ecological sustainability in India, focusing on three ecological indicators: ecological footprint (EF), CO2 emissions (CO 2 ), and load capacity factor (LF). In addition to nuclear energy, the study considers the influence of gas consumption and other drivers of ecological sustainability using data spanning from 1970 to 2018. The analysis also takes into account the impact of the 2008 global financial crisis on the model, employing the autoregressive distributed lag (ARDL) and frequency domain causality approaches to assess the relationships. Unlike previous studies, this research evaluates both the Environmental Kuznets Curve (EKC) and load capacity curve (LCC) hypotheses. The ARDL results support the validity of both the EKC and LCC hypotheses in the Indian context. Furthermore, the findings reveal that nuclear energy and human capital contribute positively to ecological quality, while gas consumption and economic growth have a negative impact on ecological sustainability. The study also highlights the increasing effect of the 2008 global financial crisis on ecological sustainability. Additionally, the causality analysis demonstrates that nuclear energy, human capital, gas consumption, and economic growth can serve as predictors of long-term ecological sustainability in India. Based on these findings, the research presents policy recommendations that can guide efforts towards achieving SDGs 7 and 13., (© 2023. The Author(s).)

The BRICS nations have yet to significantly contribute to achieving Sustainable Development Goals (SDG) 7 and 13. Dealing with this problem might necessitate a policy shift, which is the main topic of this research. Therefore, the current study scrutinizes the interrelationship between natural resources, energy, trade globalisation and ecological footprint using panel data from the period between 1990 and 2018 for the BRICS nations. To assess the interrelationship between ecological footprint and its determinants, we used the Cross sectional autoregressive distributed lag (CS-ARDL) and common correlated effects. mean group (CCEMG) estimators. The findings show that economic progress, and natural resources lessen ecological quality, while renewable energy and trade globalization improves ecological quality in the BRICS nations. Based on these results, the BRICS nations need to upgrade their use of renewable energy sources and improve the structure of their natural resource endowments. Furthermore, trade globalisation necessitates immediate policy responses in these nations since it reduces ecological damage., Competing Interests: The authors declare no conflict of interest., (© 2023 The Authors.)

This study investigates the time-frequency nexus of carbon dioxide (CO 2 ) emissions with economic growth, nonrenewable (i.e., coal, natural gas, and oil), and renewable (i.e., hydro and geothermal) energy consumption. In this context, BRICS countries (namely, Brazil, Russian Federation, India, China, and South Africa), which are leading emerging countries, are included, and quarterly data from 1990/Q1 to 2019/Q4 is used. The study employs the wavelet coherence (WC) approach to explore the co-movement between the variables at different frequencies. The empirical results show that (i) there is a strong and positive co-movement between CO 2 emission and economic growth; however, it is weak for Russia and South Africa in the medium and long-term; (ii) coal energy consumption is strongly and positively co-moved with CO 2 emission for all BRICS countries; (iii) natural gas energy consumption is strongly and positively co-moved with CO 2 emissions in Brazil, India, and China; however, it is weakly and positively co-moved in Russia and South Africa; (iv) oil energy consumption is strongly and positively co-moved with CO 2 emissions in Brazil, India, and China; however, it changes a bit for Russia and South Africa; (v) hydro energy consumption is weakly and positively co-moved with CO 2 emissions in general, whereas country-based results vary; (vi) geothermal energy consumption is also similar to hydro energy consumption. Thus, the WC results highlight the strong co-movement of economic growth and nonrenewable energy consumption with CO 2 emissions, whereas renewable energy consumption has a relatively lower co-movement. Based on the results, policy implications are also discussed for BRICS countries., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

This research aimed to examine the complex interaction between technological innovation, renewable energy consumption, natural resources, and carbon dioxide (CO 2 ) emissions of BRICS (i.e., Brazil, Russia, India, China, and South Africa) countries from 1990 to 2019, to accomplish the Paris Climate Conference (COP-21) objective of reducing CO 2 emissions to promote environmental sustainability. The long-run empirical estimations derived from the CS-ARDL technique, which considered other estimation issues like cross-sectional dependency and slope heterogeneity, indicated that technological innovation, renewable energy consumption, and natural resources increase environmental sustainability by limiting CO 2 emissions, in the short-run and long-run. The technological innovation-related activities have a CO 2 mitigating effect as shown by the negative coefficients which ranges between -0.05 and -0.14. This shows that they increase environmental sustainability and aid in achieving Sustainable Development Goals (SDGs) 13. Similarly, renewable energy and natural resources decrease CO 2 emissions as shown by the coefficient of renewable energy (-0.31 to -0.81) and natural resources (-0.01 to 0.95); thereby increasing ecological quality by limiting CO 2 emissions. Furthermore, the interaction of technological innovation with natural resource rent and renewable energy consumption also aids in mitigating CO 2 emissions and increases environmental health. Finally, panel causality analysis revealed a significant causality from all explanatory variables to CO 2 emissions. Based on the results, significant policy suggestions are provided, such as improving energy effectiveness, investing in energy technologies, and increasing renewable energy consumption to stimulate technological innovation to achieve the target of a net-zero‑carbon economy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

This study focuses on uncovering the effect of country risks and renewable energy consumption on environmental quality. In this context, the study examines Mexico, Indonesia, Nigeria, and Turkey (MINT) nations; takes economic growth, trade openness, and urbanization into account; includes data from 1990 to 2018; applies cross-sectional autoregressive distributed lag (CS-ARDL) as the main model while common correlated effects mean group (CCEMG) and augmented mean group (AMG) for robustness checks. The empirical results show that (i) economic growth, political risk, urbanization, and trade openness contribute to an increase in ecological footprint; (ii) economic and financial risks as well as renewable energy use have a positive influence on environmental quality; (iii) a unidirectional causality exists from economic risk, financial risk, political risk, economic growth, urbanization, and trade openness to the ecological footprint: (iv) the validity of the EKC hypothesis for the MINT economies is verified; (v) the robustness of CS-ARDL results are validated by CCEMG and AMG approaches. Based on these results, policymakers should promote a sustainable environment to lessen the ecological footprint. Additionally, governments should firmly support investments in green technology as well as economic and financial stability to boost energy efficiency and promote the adoption and usage of energy-saving products., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)