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This study integrated hydrochemical analysis, isotopic analysis, the integrated water quality index (IWQI), and the health risk assessment model to analyze hydrochemical characteristics, quality, and nitrate health risks in a typical agricultural and industrial (i.e., Holocene and Pleistocene) simultaneously affected by anthropogenic activities, as well as to explore the recharge mechanisms of the groundwater. The shallow groundwater is mainly Ca-HCO3− and deep groundwater is mainly Na-HCO3− types. In shallow and intermediate aquifers (Holocene), rainfall recharge is seen, but in deep aquifers (Holocene) and the Madhupur tract (Pleistocene), there is no evidence of recent recharge from the stable isotopic (δ2H‰ and δ18O‰) composition of groundwater. Anthropogenic sources significantly impacted the groundwater chemistry of shallow and intermediate aquifers more than geogenic sources. Most metalloids, and metals (As, and Cr, Fe, Ni, Pb, and Mn) and NO3− exceed the WHO-2011 and BD acceptable limit from shallow and intermediate groundwater. PCA analysis revealed the contamination of shallow and intermediate aquifers by metalloids, metals and from various anthropogenic activities. Based on the IWQI, HPI, HEI, and DC, groundwater samples from shallow and intermediate aquifers are unsuitable for oral consumption. The NPI shows that the metalloids, and metals are responsible for groundwater pollution in a descending order of As > Fe > Pb > Ni > Cr > Mn. Health risk assessment indicates oral and dermal consumption of contaminated water from shallow and intermediate aquifers can pose carcinogenic and non-carcinogenic health risks for both the adults and the children. The HQ and HI values of shallow and intermediate groundwater indicates higher non-carcinogenic risk. Carcinogenic risk through oral and dermal consumption follows an order of As > Ni > Cr > Pb and Ni > Cr > As > Pb, respectively. Compared to adults, children are more susceptible to both carcinogenic and non-carcinogenic risks. Potential threats to the health of people living in the study region need immediate attention from the public, government, and the scientific community. [ABSTRACT FROM AUTHOR]

The fundamental relationship between structure and properties, which is called "structure‐property", plays a vital role in the rational designing of high‐performance catalysts for diverse electrocatalytic applications. Low‐dimensional (LD) nanomaterials, including 0D, 1D, 2D materials, combined with low‐nuclearity metal atoms, ranging from single atoms to subnanometer clusters, are currently emerging as rising star nanoarchitectures for heterogeneous catalysis due to their well‐defined active sites and unbeatable metal utilization efficiencies. In this work, a comprehensive experimental and theoretical review is provided on the recent development of single atom and atomic cluster‐decorated LD platforms towards some typical clean energy reactions, such as water‐splitting, nitrogen fixation, and carbon dioxide reduction reactions. The upmost attractive structural properties, advanced characterization techniques, and theoretical principles of these low‐nuclearity electrocatalysts as well as their applications in key electrochemical energy devices are also elegantly discussed. [ABSTRACT FROM AUTHOR]

Low dimensional electrocatalytic heterostructures have recently attracted significant attention in the catalysis community due to their highly tuneable interfaces and exciting electronic features, opening up new possibilities for effective nanometric control of both the charge carriers and energetic states of several intermediate catalytic species. In-depth understanding of electrocatalytic routes at the interface between two or more low-dimensional nanostructures has triggered the development of heterostructure nanocatalysts with extraordinary properties for water splitting reactions, NRR and CO2RR. This tutorial review provides an overview of the most recent advances in synthetic strategies for 0D–1D, 0D–2D, and 2D–2D nanoheterostructures, discussing key aspects of their electrocatalytic performances from experimental and computational perspectives as well as their applications towards the development of overall water splitting and Zn–air battery devices. [ABSTRACT FROM AUTHOR]

Recently, the advantages of biopolymers over conventional plastic polymers are unprecedented, provided that they are used in situations in which they raise the functionality and generate extra benefits for human life. Therefore, biopolymers have received much attention because they play an important place in day-to-day life for their specific tunable characteristics, making them attractive in a wide range of applications. Biopolymers can produce materials with tunable properties such as biodegradability, biocompatibility, renewability, inexpensiveness, availability, which are critically important for designing materials for use in biomedical applications. In addition to these properties, smart biopolymers could be prepared by changing the polymer components, which would create more target oriented applications. Therefore, this review interprets how biopolymers and their various forms can be potentially used in biomedical applications, including drug delivery, infections, tissue engineering, wound healings, and other as wells. Special emphasis will be provided on the applications of biopolymers in the field of drug delivery, tissue engineering, infections, and wound healing, which indicate the advancement and employment of the various biopolymers in recent biomedical applications. [ABSTRACT FROM AUTHOR]

Correction for 'Spent tea leaves templated synthesis of highly active and durable cobalt-based trifunctional versatile electrocatalysts for hydrogen and oxygen evolution and oxygen reduction reactions' by Md Ariful Ahsan et al., Green Chem., 2020, 22, 6967–6980, https://doi.org/10.1039/D0GC02155E. [ABSTRACT FROM AUTHOR]

Nature-inspired hierarchical architectures have recently drawn enormous interest in the materials science community, being considered as promising materials for the development of high-performance wearable electronic devices. Their highly dynamic interfacial interactions have opened new horizons towards the fabrication of sustainable sensing and energy storage materials with multifunctional properties. Nature-inspired assemblies can exhibit impressive properties including ultrahigh sensitivity, excellent energy density and coulombic efficiency behaviors as well as ultralong cycling stability and durability, which can be finely tuned and enhanced by controlling synergistic interfacial interactions between their individual components. This tutorial review article aims to address recent breakthroughs in the development of advanced Nature-inspired sensing and energy storage materials, with special emphasis on the influence of interfacial interactions over their improved properties. [ABSTRACT FROM AUTHOR]

An emerging class of heterostructures with unprecedented (photo)electrocatalytic behavior, involving the combination of fullerenes and low‐dimensional (LD) nanohybrids, is currently expanding the field of energy materials. The unique physical and chemical properties of fullerenes have offered new opportunities to tailor both the electronic structures and the catalytic activities of the nanohybrid structures. Here, we comprehensively review the synthetic approaches to prepare fullerene‐based hybrids with LD (0D, 1D, and 2D) materials in addition to their resulting structural and catalytic properties. Recent advances in the design of fullerene‐based LD nanomaterials for (photo)electrocatalytic applications are emphasized. The fundamental relationship between the electronic structures and the catalytic functions of the heterostructures, including the role of the fullerenes, is addressed to provide an in‐depth understanding of these emerging materials at the molecular level. [ABSTRACT FROM AUTHOR]

An emerging class of heterostructures with unprecedented (photo)electrocatalytic behavior, involving the combination of fullerenes and low‐dimensional (LD) nanohybrids, is currently expanding the field of energy materials. The unique physical and chemical properties of fullerenes have offered new opportunities to tailor both the electronic structures and the catalytic activities of the nanohybrid structures. Here, we comprehensively review the synthetic approaches to prepare fullerene‐based hybrids with LD (0D, 1D, and 2D) materials in addition to their resulting structural and catalytic properties. Recent advances in the design of fullerene‐based LD nanomaterials for (photo)electrocatalytic applications are emphasized. The fundamental relationship between the electronic structures and the catalytic functions of the heterostructures, including the role of the fullerenes, is addressed to provide an in‐depth understanding of these emerging materials at the molecular level. [ABSTRACT FROM AUTHOR]

The rational design of high-performance trifunctional catalysts for oxygen reduction and oxygen and hydrogen evolution reactions is of vital importance for the implementation of green energy conversion technologies. Herein, trifunctional electrocatalysts comprising cobalt nanoparticles uniformly embedded in porous carbon networks were fabricated using a spent tea leaves (STL) template via a one-step carbothermal-reduction strategy at different temperatures. STL played a synthetic dual role in constructing nanocatalysts by acting as efficient scavengers to trap cobalt cations via electrostatic interactions and as carbon sources to generate a porous carbon matrix. Full characterization of the as-synthesized materials revealed the crucial effect of temperature on the crystallinity, surface area, number of surface defects and interfacial charge distribution properties. Furthermore, the trifunctional catalytic activity of the nanoparticles can be finely tuned by varying the carbonization temperature. Co@PC-7 displayed a superior trifunctional catalytic activity exhibiting an excellent performance for hydrogen production with an overpotential of 153 mV (vs. RHE) to achieve 10 mA cm−2, and an impressive bifunctional oxygen electrocatalytic activity with an ultralow potential difference between OER and ORR (ΔE = η10 − E1/2) of 0.69 V, which is one of the lowest values reported in the literature for transition metal nanocatalysts. The remarkable performance of Co@PC-7 is mainly ascribed to its unique structural properties, which give rise to highly desirable charge distributions at the metal/carbon electrochemical interfaces to perform efficient trifunctional water splitting electrocatalysis. [ABSTRACT FROM AUTHOR]

In recent years, the incorporation of molecular enzymes into nanostructured frameworks to create efficient energy conversion biomaterials has gained increasing interest as a promising strategy owing to both the dynamic behavior of proteins for their electrocatalytic function and the unique properties of the synergistic interactions between proteins and nanosized materials. Herein, we review the impact of proteins on energy conversion fields and the contribution of proteins to the improved activity of the resulting nanocomposites. We address different strategies to fabricate protein-based nanocatalysts as well as current knowledge on the structure–function relationships of enzymes during the catalytic processes. Additionally, a comprehensive review of state-of-the-art bioelectrocatalytic materials for water-splitting reactions such as hydrogen evolution reaction (HER) and oxygen evolution reactions (OER) is afforded. Finally, we briefly envision opportunities to develop a new generation of electrocatalysts towards the electrochemical reduction of N2 to NH3 using theoretical tools to built nature-inspired nitrogen reduction reaction catalysts. [ABSTRACT FROM AUTHOR]

A simple and facile stereolithography 3D printing technique was utilized to fabricate piezoelectric photopolymer-based polyvinylidene fluoride (PVDF) blends. Different process variables, such as solvent (N , N -dimethylformamide, DMF) to PVDF ratio and PVDF solution to photopolymer resin (PR) ratio, were engineered to enhance the dispersion of the PVDF into the PR so as to achieve the maximum piezoelectric coupling coefficient. Our results demonstrate that a ratio of 1:10 (PVDF:DMF) and 2 wt%-PVDF/PR was optimal for the best dissolution of the PVDF, 3D printability, and piezoelectric properties. Under these conditions, the blend generated ±0.121 nA under 80 N dynamic loading excitation. We believe that the findings of this work would promote many further studies on the mass production of flexible piezoelectric polymer blends with higher quality finished surface and design flexibility. [ABSTRACT FROM AUTHOR]

A simple and facile method was developed to fabricate functional bulk barium titanate (BaTiO3, BT) ceramics using the paste extrusion 3D printing technique. The BT ceramic is a lead‐free ferroelectric material widely used for various applications in sensors, energy storage, and harvesting. There are several traditional methods (eg, tape casting) to process bulk BT ceramics but they have disadvantages such as difficult handing without shape deformation, demolding, complex geometric shapes, expansive molds, etc. In this research, we utilized the paste extrusion 3D printing technique to overcome the traditional issues and developed printable ceramic suspensions containing BT ceramic powder, polyvinylidene fluoride (PVDF), N,N‐dimethylformamide (DMF) through simple mixing method and chemical formulation. This PVDF solution erformed multiple roles of binder, plasticizer, and dispersant for excellent manufacturability while providing high volume percent and density of the final bulk ceramic. Based on empirical data, it was found that the maximum binder ratio with good viscosity and retention for desired geometry is 1:8.8, while the maximum BT content is 35.45 vol% (77.01 wt%) in order to achieve maximum density of 3.93 g/cm3 (65.3%) for 3D printed BT ceramic. Among different sintering temperatures, it was observed that the sintered BT ceramic at 1400°C had highest grain growth and tetragonality which affected high performing piezoelectric and dielectric properties, 200 pC/N and 4730 at 103 Hz respectively. This paste extrusion 3D printing technique and simple synthesis method for ceramic suspensions are expected to enable rapid massive production, customization, design flexibility of the bulk piezoelectric and dielectric devices for next generation technology. [ABSTRACT FROM AUTHOR]

The thermoelectric effect encompasses three different effects, i.e. Seebeck effect, Peltier effect, and Thomson effect, which are considered as thermally activated materials that alter directions in smart materials. It is currently considered one of the most challenging green energy harvesting mechanisms among researchers. The ability to utilize waste thermal energy that is generated by different applications promotes the use of thermoelectric harvesters across a wide range of applications. This review illustrates the different attempts to fabricate efficient, robust and sustainable thermoelectric harvesters, considering the material selection, characterization, device fabrication and potential applications. Thermoelectric harvesters with a wide range of output power generated reaching the milliwatt range have been considered in this work, with a special focus on the main advantages and disadvantages in these devices. Additionally, this review presents various studies reported in the literature on the design and fabrication of thermoelectric harvesters and highlights their potential applications. In order to increase the efficiency of equipment and processes, the generation of thermoelectricity via thermoelectric materials is achieved through the harvesting of residual energy. The review discusses the main challenges in the fabrication process associated with thermoelectric harvester implementation, as well as the considerable advantages of the proposed devices. The use of thermoelectric harvesters in a wide range of applications where waste thermal energy is used and the impact of the thermoelectric harvesters is also highlighted in this review. [ABSTRACT FROM AUTHOR]

In recent years, the incorporation of molecular enzymes into nanostructured frameworks to create efficient energy conversion biomaterials has gained increasing interest as a promising strategy owing to both the dynamic behavior of proteins for their electrocatalytic function and the unique properties of the synergistic interactions between proteins and nanosized materials. Herein, we review the impact of proteins on energy conversion fields and the contribution of proteins to the improved activity of the resulting nanocomposites. We address different strategies to fabricate protein-based nanocatalysts as well as current knowledge on the structure–function relationships of enzymes during the catalytic processes. Additionally, a comprehensive review of state-of-the-art bioelectrocatalytic materials for water-splitting reactions such as hydrogen evolution reaction (HER) and oxygen evolution reactions (OER) is afforded. Finally, we briefly envision opportunities to develop a new generation of electrocatalysts towards the electrochemical reduction of N2 to NH3 using theoretical tools to built nature-inspired nitrogen reduction reaction catalysts. [ABSTRACT FROM AUTHOR]