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The water shortage crisis and industrial progress have led to the upgrading of wastewater treatment processes. Hence, the remediation of wastewater and removal of contaminants are becoming a significant issue for environmentalists. However, the design and optimization of affordable treatment procedures with better removal performance are still challenging for researchers. Although porous ceramics with excellent porosity are appropriate for the separation and adsorption of wastewater and water pollutants owing to their enlarged surface area, fluid permeability, and capacity for water absorption, their production is an expensive process. Therefore, using low‐cost and benign compounds for the production of ceramics is an important issue. This review provides the application of the ceramic manufactured from natural sources and biomass for wastewater treatment and removal of pollutants. The effect of these compounds on the structure and efficiency of ceramics is discussed and suggestions are offered for further research. [ABSTRACT FROM AUTHOR]

Industrialization and the increasing amount of by-products and residues released from industrial activities have triggered an urgent demand for the development of clean energy storage and conversion systems to eradicate or minimize the use of environmentally noxious matter. In this case, nature-inspired materials present significant potential as catalysts and nanofillers for the preparation of electrodes and nanocomposites for energy storage and conversion. These materials possess extended porous architectures, high surface areas, considerable mechanical and thermal stability, abundant reserves, and low cost. In this review, we summarize the structure and classification of natural materials that make them appropriate for application in energy storage and conversion devices. Furthermore, we focus on the applications and new advancements of nature-inspired materials in fuel cells, given that they enhance the performance of fuel cell technology. [ABSTRACT FROM AUTHOR]

Polycarbonate (PC)-ZnO films with different percentages of ZnO were prepared by a solution stirring technique and subjected to ultraviolet (UV; λ = 254 nm) irradiation. Structural parameters of the samples and the effects of UV irradiation on the surface properties of the PC and PC-ZnO nanocomposites were evaluated by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), water contact angle (WCA) measurements, and a Vickers microhardness (HV) tester. The XRD patterns of the nanocomposite films were found to show an increase in crystallinity with the increasing ZnO nanoparticles percentage. The WCA was found to be reduced from 90° to 17° after 15 h of UV irradiation, which could be ascribed to the oxidation of the surface of the samples during the irradiation and exposure of the ZnO nanoparticles, a result that is also supported by the obtained XPS data. The microhardness value of the PC-ZnO films including 30 wt.% ZnO enhanced considerably after UV radiation, which can also be attributed to the exposition of the ZnO nanoparticles after photodegradation of the PC superficial layer of the nanocomposite films. [ABSTRACT FROM AUTHOR]

The article offers information on decrease in quality and quantity of Iran's groundwater. It also include how Iran's climate varies from arid to semiarid and use of groundwater is three times higher than the global average.

Global reduction of traditional fuel sources such as natural gases, coal, and petroleum has led researchers to seek prominent and beneficial energy conversion devices. Fuel cells are a newfound and upcoming energy generation systems that have progressed rapidly. Fuel cells are popular eco-friendly devices among different energy conversion devices due to their cost-effectiveness and high output. In a fuel cell composed of a cathode, anode, and electrolyte, the electrical energy is produced through chemical reactions. Various fuels such as H 2 , alcohols, especially ethanol and methanol, and formic acid are applied in fuel cells. Large scale application of this technology mainly depends on two aspects, including one is the possibility to produce on a large scale and accessible cost-efficient catalytic materials (anodic and cathodic), and second is the stable and high performing membrane in fuel cells. Among various investigated materials, carbon supports and metal-free carbon materials are widely used in fuel cell devices, which increases their overall electrochemical surface area (ECSA) and performance. Carbon-based materials with high surface area, excellent electrical conductivity, and high porosity is known to be a primary substrate for electrochemical energy storage applications such as batteries, supercapacitors, and fuel cells. Herein, we have reviewed the efficacy of carbon-based materials on electrocatalytic activity, stability, and output performance of different fuel cells. Fuel cells are promising converter energy devices. The high surface area, high porosity, and electrical conductivity of carbon support effectively increase the activity of fuel cells. Herein, we have critically overviewed the information about the role of carbon-based materials for the fuel cells performance and output. [Display omitted] • Carbon-based materials show remarkable potential for fuel cell performance. • Fuel cell application of (metal-free)carbon-based catalysts has been reviewed. • Various carbon materials in different fuel cells are discussed in detail. • The fuel cell's performance in understanding their electrochemical reactions have been studied. • Future research directions and challenges in the field of fuel cells have been discussed. [ABSTRACT FROM AUTHOR]

Carbon nanoparticles (CNPs) with high porosity and great optical features can be used as a luminescent material. One year later, the same group investigated the NLO properties CNPs and boron-doped CNPs by 532 nm and 1064 nm laser excitations to uncover the underlying physical mechanisms in their NLO response. Hence, a facile approach, laser ablation technique, was employed for carbon nanoparticles (CNPs) synthesis from suspended activated carbon (AC). Morphological properties of the prepared CNPs were studied by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). UV-Vis and fluorescence (FL) spectra were used to optical properties investigation of CNPs. The size distribution of nanoparticles was evaluated using dynamic light scattering (DLS). The nonlinear optical (NLO) coefficients of the synthesized CNPs were determined by the Z-scan method. As a result, strong reverse saturable absorption and self-defocusing effects were observed at the excitation wavelength of 442 nm laser irradiation. These effects were ascribed to the presence of delocalized π-electrons in AC CNPs. To the best of our knowledge, this is the first study investigating the NLO properties of the AC CNPs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Preparation of TiO 2 /RGO nanocomposite by annealing method at 180 °C. • Employing TiO 2 /RGO nanocomposite toward sensing methanol, ethanol and acetone vapors with different ppm. • Observation an excellent response for ethanol detection even in low gas volume. Reduced graphene oxide and metal oxides derivatives are introduced as relatively benign materials for improving gas sensors' performance as exemplified by the synthesis of TiO 2 /GO nanocomposite via ultrasonication, and then the assembly of RGO adorning TiO 2 nanoparticles (NPs) (TiO 2 /RGO) is accomplished using the thermal annealing method. The characterization of the as-fabricated sample indicated that irregular shaped TiO 2 NPs with size of 26 nm covered the RGO nanosheets. The optical band gap measurement indicated the values of 3.19, 2.1 and 2.5 eV for TiO 2 , GO and TiO 2 /RGO samples, respectively. The ensued nanocomposites are then deployed for the gas sensing response of three common organic vapors of ethanol, methanol, and acetone with concentrations of 20, 40, 60, 80, 100 ppm, at ambient temperature. The TiO 2 /RGO sensor relatively exhibited an excellent response (3–4 times) for ethanol detection. These results indicated that the application of TiO 2 /RGO can help assist in the evolvement of portable gas sensing devices endowed with the capability to detect common place organic vapors. [ABSTRACT FROM AUTHOR]

Pt-nanofluids with localized surface plasmon resonance (LSPR) property were environmentally-friendly prepared using the laser ablation in liquids (LAL) while H 2 O acts as a working fluid. Based on transmission electron microscopy (TEM), the obtained Pt nanoparticles have an average diameter of 6 nm which were strongly surrounded with H 2 O molecules, leading to excellent longtime durability. Moreover, fluorescence spectroscopy and fluorescence microscopy images indicated that the prepared sample has fluorescence property that makes it capable to absorb more light and then, to convert it to heat. The Pt-nanofluids were applied for light to heat conversion. After several continuous heating/cooling cycles, the prepared nanofluids did not lose their efficiency in terms of light to heat conversion. In addition, the potential of the Pt-nanofluids in harvesting solar energy was investigated. The infrared thermographs proved that the upper layer temperature of the Pt-nanofluids reached > 49 °C after 60 min light illumination, under ≅ 0.9 Sun intensity. The obtained results proved that the prepared Pt-nanofluids have outstanding advantages, consist of fast, simple, and green synthesis method, no necessity for dispersant, high thermal-stability, long-time stability, and high performance in photo-thermal conversion. So, the Pt-nanofluids have high capability for practical solar energy utilization. [Display omitted] • Pt-nanofluids were synthesized via one step and fast LAL method. • Pt-nanofluids used for photo-thermal conversion for consecutive cycles without losing its performance. • The prepared Pt-nanofluids have long life and thermal stability. • Pt-nanofluids used for solar energy harvesting. [ABSTRACT FROM AUTHOR]

Over the course of a few decades, the concern of environmental damages of fossil fuels, an increase in CO 2 emission and a decrease of hydrogen have been growing more and more. Accordingly, hydrogen production is a crucial issue nowadays. Different polymers are applied to attain the purpose. Among all polymers, biodegradables polymers are the best choices to develop the main aim. Polysaccharides and proteins are biodegradable polymers with unique places and advantages with regards to their ecofriendly properties. There are different techniques to apply and achieve the foremost purpose. It is worthwhile to mention that green and facile methods are always attracting attention in different aspects and fields. The three non-polluting and economical techniques, that is, electrochemical hydrogen evolution reaction (HER), photocatalytic technique, and hydrolysis of hydrides, are reviewed in this paper. This review helps researchers, who are environment supporters, to evaluate and choose the most ecological biopolymers and processes in their work. [Display omitted] • Developments in hydrogen evolution by biopolymer-derived (nano)catalysts have been described. • Summary of synthetic procedures to obtain biopolymer-derived (nano)catalysts. • Future challenges of hydrogen evolution using biopolymer-derived (nano)catalysts have been discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Facile synthesis of Au NPs on zirconia NPs by laser ablation in liquid (LAL) protocol. • A high-performance strategy for NaBH 4 -mediated degradation of MO and MB in water. • Characterization of ZrO 2 -Au nanocomposite via XRD, FTIR, SEM, EDS, XPS, BET, and MAP analyses. • The ZrO 2 -Au nanocomposite can be reused several times with almost no loss in activity. The continuous development of industrial activities and also changing climate of worldwide lead to increase water pollutants and the eradication of safe water sources. Hence, remediation of wastewater and reduction of water pollutants notably organic dyes have become a serious environmental challenge. Reducing organic pollutants by heterogeneous nanocatalysts can be employed as an efficacious manner to overcome this problem. Accordingly, a nanocomposite catalyst consisting of zirconium oxide or zirconia nanoparticles (ZrO 2 NPs) and gold (Au) NPs were made by means of a straightforward and green route. Au NPs were firstly prepared via laser ablation in liquid (LAL) method and then deposited on the ZrO 2 NPs with the size of 53–88 nm using the magnetic stirring approach. The characterization methods indicated that the ZrO 2 -Au nanocomposite was successfully fabricated. The catalytic performance of ZrO 2 -Au catalyst for the degradation of methylene orange (MO) and methylene blue (MB) was investigated. [ABSTRACT FROM AUTHOR]

Today, the increasing world population has led to increased consumption of fossil fuels for energy production, causing environmental problems. Hydrogen with high energy density can be used as a suitable alternative to fossil fuel sources. Hydrogen atoms can be stored on porous structures by physical interaction. Hence, simple and eco-friendly approaches have been taken to prepare bentonite/Pd nanocomposites for electrochemical hydrogen storage. Laser ablation in the deionized water medium was employed as a physical route for the synthesis of Pd nanoparticles (NPs). Bentonite, a porous substrate with a high surface area of 47 m2/g, was employed for the deposition of Pd NPs via physical mixing. The morphological study of nanocomposite indicated that the spherically shaped Pd NPs with a diameter of 20–27 nm are successfully deposited on the bentonite substrate. The as-prepared nanocomposites were loaded on stainless steel electrode through drop-casting and their hydrogen storage capacity was determined via cyclic voltammetry (CV). The CV measurement of the B/Pdx electrodes (x is laser ablation times of 15, 30, 45, and 60 min) in 1.0 M KOH electrolyte at the scan rate of 100 mV/s at room temperature demonstrated good hydrogen storage capacity (37 C/g) and stability during 200 scans. [Display omitted] • The LAL method was applied as an eco-friendly approach for preparation of Pd NPs. • Pd NPs were deposited on the bentonite via physical mixing. • Electrochemical hydrogen storage performance of B/Pd was evaluated by CV. • Electrochemical hydrogen storage capacity of B/Pd30 was obtained 37 C/g. [ABSTRACT FROM AUTHOR]