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In the current research work, an Al-Si-Mg aluminum alloy-based composite (AMCs) was prepared via stir casting. The AA6082 matrix was incorporated with 0, 3, 6 and 9 wt.-% zirconium diboride (ZrB2) particles for manufacturing composites. The manufactured AA6082/ZrB2 composites were evaluated by employing scanning electron microscope (SEM) and X-ray diffraction (XRD). Flexural strength, macro-hardness and wear rate of the composites were examined. XRD confirms the development of ZrB2 peaks and also proves that no reaction products are found in the AMCs. The SEM examination depicts the homogeneous dissemination of ZrB2 in the Al alloy. The tribological and mechanical characterization of the AMCs improved after the inclusion of ZrB2 contents. The experimental outcomes attained indicate that the tribological and mechanical behavior of the AMCs was enriched by an escalation in mass proportionate to the ZrB2 filler content.

Titanium dioxide (TiO2) has been acknowledged as one of the efficient photocatalysts in the UV region. To extend the photo-absorption region toward visible lights, the TiO2 nanowires enclosed with carbon shells (TiO2@carbon core-shell nanowires) were synthesized by a chemical vapor deposition technique at various temperatures from 650 to 950 °C. The transmission electron microscopy (TEM) and X-ray diffraction (XRD) analyses revealed that TiO2 cores and carbon shells are rutile and graphitic structures, respectively. From Raman spectra, the peak intensity of the Eg mode was observed to be redshifted with elevated growth temperatures due to the increase in oxygen vacancies in the TiO2@carbon core-shell nanowires. From X-ray photoelectron spectroscopy (XPS) results, the oxygen vacancies were strongly related to the Ti3+ ions. The UV–visible spectroscopic studies show a possible decrease in photocatalytic energy from 3.1 to 2.7 eV for the TiO2@carbon core-shell nanowires, indicating that the light absorption was enhanced in the visible-light region. The optical absorbance results confirmed the presence of the mid-gap states due to the oxygen vacancies, which are responsible for the visible-light absorption. The photocatalytic activity of the TiO2@carbon core-shell nanowires studied by methylene blue (MB) dye degradation is effective under visible lights.

Aluminum-sulfur batteries (ASBs) have attracted substantial interest due to their high theoretical specific energy density, low cost, and environmental friendliness, while the traditional sulfur cathode and ionic liquid have very fast capacity decay, limiting cycling performance because of the sluggishly electrochemical reaction and side reactions with the electrolyte. Herein, we demonstrate, for the first time, excellent rechargeable aluminum-selenium batteries (ASeBs) using a new deep eutectic solvent, thiourea-AlCl3, as an electrolyte and Se nanowires grown directly on a flexible carbon cloth substrate (Se NWs@CC) by a low-temperature selenization process as a cathode. Selenium (Se) is a chemical analogue of sulfur with higher electronic conductivity and lower ionization potential that can improve the battery kinetics on the sluggishly electrochemical reaction and the reduction of the polarization where the thiourea-AlCl3 electrolyte can stabilize the side reaction during the reversible conversion reaction of Al-Se alloying processes during the charge-discharge process, yielding a high specific capacity of 260 mAh g-1 at 50 mA g-1 and a long cycling life of 100 times with a high Coulombic efficiency of nearly 93% at 100 mA g-1. The working mechanism based on the reversible conversion reaction of the Al-Se alloying processes, confirmed by the ex situ Raman, XRD, and XPS measurements, was proposed. This work provides new insights into the development of rechargeable aluminum-chalcogenide (S, Se, and Te) batteries.

Hierarchical nano-/microstructured photocatalysts have drawn attention for enhanced photocatalytic performance. Deep eutectic solvents (DESs) have been used as a green sustainable media to act as both solvent and structure-inducing agent in the synthesis of hierarchical nanomaterials. In this work, the DESs-assisted synthesis of flower-structured BiOCl/BiVO4 (BOC/BVO) with g-C3 N4 (BOC/BVO/g-CN) ternary heterojunctions was achieved by using a simple wet-chemical method, providing good acidic and alkaline oxygen evolution reaction (OER) catalysts. BOC/BVO/g-CN-15 achieved an enhanced photocatalytic activity for OER with an overpotential of 570 mV in 1 m H2 SO4 and 220 mV in 1 m KOH electrolyte at a current density of 10 mA cm-2 with excellent stability and extraordinary durability of the catalyst. The ternary heterojunctions displayed extended lifetimes for photogenerated charges and enhanced the separation efficiency of photogenerated electron-hole pairs, which is helpful to enhance the photocatalytic OER. Furthermore, the photocatalytic performance of the ternary heterojunctions in aqueous solution was demonstrated through photocatalytic dye degradation of methyl orange (MO) as a model pollutant, resulting in 95 % degradation of 20 ppm of MO in 210 min under the irradiation of a 35 W Xe arc lamp. This work not only provides new insight into the design of catalysts by using green solvents but also into the design of highly efficient metal-free OER photocatalysts for applications in acidic and alkaline media.

Recently, extracting hot electrons from plasmonic nanostructures and utilizing them to enhance the optical quantum yield of two-dimensional transition-metal dichalcogenides (TMDs) have been topics ...

In this work, the microencapsulated phase change materials, Sn/amorphous-carbon (Sn/a-C), and SnBi/amorphous carbon (SnBi/a-C) microparticles (MPs) were successfully synthesized. The thermal stabilities of Sn/a-C and SnBi/a-C core-shell MPs were verified by cycling tests, and stable latent heats of 56 and 45.7 J/g were obtained for Sn/a-C and SnBi/a-C MPs, respectively. Compared to the high melting point of 231 °C and large thermal hysteresis (TH) of ∼106 °C for the Sn/a-C MPs, the SnBi/a-C MPs exhibited a lower melting point of 125 °C and a smaller TH of 20 °C. The nitrate senary salt with a lower melting point of ∼75 °C than that of the commercial HITEC salt (melting point of ∼142 °C) was also synthesized to enlarge the working temperature range of the working fluid in a solar thermal power plant and to demonstrate the latent heat-enhanced thermal energy storage using the SnBi/a-C MPs. The heat capacity can be enhanced by 200% by doping with 20 wt % Sn/a-C MPs into the HITEC salt, and it can be enhanced by 734% by doping with 20 wt % SnBi/a-C MPs into the senary salt. In addition, the viscosities of the HITEC salt and senary salt doped with the Sn/a-C and SnBi/a-C MPs were not appreciably raised by doping with the MPs. The various approaches accomplished in this work demonstrate (1) enhancing heat capacity of the working fluid by exploiting the latent heats of the embedded MPs; (2) lowering the TH of the MPs by using the alloy metal particles; and (3) extending the working temperature range by synthesizing the senary salt. These approaches could be applied for enhancing energy storage in solar thermal power plants and facilitating waste heat recovery., This research was supported by the Ministry of Science and Technology through grants no 110-2622-E-007 -017, 110-2634-F-007-023-, 110-2112-M-007-032-MY3, 110-2221-E-007-057-MY3 and 110-2119-M-007 -003 -MBK. The authors gratefully acknowledge the use of HRTEM and SPM equipment belonging to the Instrument Center of National Tsing Hua University. Y.-L.C. greatly appreciates the use of the facility at CNMM.

In recent years, the diverse industrial practices and human inputs widely disseminated emerging contaminants (ECs) throughout environmental matrices, which is of great concern. Even at low concentrations, ECs pose major ecological problems and threaten human health and the environment’s biota. Consequently, people’s interest and concerns on the widespread dissemination of environmentally connected ECs of great concern as developed due to their scientific understanding, technical innovation, and socioeconomic awareness. Increased detection of contaminants may occur from climatic, socioeconomic, and demographic changes and the growing sensitivity of analytical techniques. Hence, this article reviews the determination of ECs in ecological specimens, from aquatic setup (river water, marine water, and wastewater), sludge, soil, sediment, and air. Sample collection and the quality measures are summarized. The preparation of samples, including extraction and cleanup and the subsequent instrumental analysis of ECs, are all covered. Traditional and recent extraction and cleanup applications to analyze ECs in samples are reviewed here in this paper. The detection and quantification of ECs using gas chromatography (GC) and liquid chromatography (LC) linked with various detectors, particularly mass spectrometry (MS), is also summarized and explored, as are other possible techniques. This study aims to give readers a more excellent knowledge of how new and improved approaches are being developed and serve as a resource for researchers looking for the best method for detecting ECs in their studies.

Microalgae have been publicized for their diversified dominance responsiveness and bioaccumulation potential toward pollutants in an ecosystem. Also, algal's incredible capability as biocatalysts in environmental appliances has been well elucidated owing to their robustness and simple nutritional demand. Additionally, microalgae can deliver various collections of bio-based chemical compounds helpful for diversified applications, especially as green alternatives. The environment has been contaminated with various polluting agents; one principal polluting agent is heavy metals which are carcinogenic and show toxicity even in minimal quantity, cause unsatisfactory threats to the environmental ecosystem, including human and animal health. There is a prominent tendency to apply microalgae in the phytoremediation of heavy metals compounds because of its vast benefits, including great accessibility, cost-effective, excellent toxic metal eliminating efficiency, and nontoxic to the ecosystem. This review uncovers the most recent advancements and mechanisms associated with the bioremediation process and biosorption interaction of substantial harmful synthetic compounds processing microalgae species. Furthermore, future challenges and prospects in the utilization of microalgae in heavy metals bioremediation are also explored. The current review aims to give valuable information to aid the advancement of robust and proficient future microalgae-based heavy metal bioremediation innovations and summarizing a wide range of benefits socioeconomic scope to be employed in heavy metal compound removal in environment system.

The ever-rising environmental problems because of heavy metals emerging from anthropogenic activities pose an impending threat to all biota globally. Considering their persistence and possibility in biomagnification, they are prominent among pollutants. There has been an apparent shift of research interest in advancing cost-effective and competent technologies to mitigate environmental contaminants, specifically heavy metals. In the recent two decades, tailored nanomaterials (NMs), nanoparticles, and NM-based adsorbents have been emerging for removing heavy metal pollution on a sustainable scale, especially the green synthesis of these nanoproducts effective and nonhazardous means. Hence, this review explores the various avenues in nanotechnology, an attempt to gauge nanotechnological approaches to mitigate heavy metals in the aqueous system, especially emphasizing the recent trends and advancements. Inputs on remediating heavy metal in sustainable and environmentally benign aspects recommended future directions to compensate for the voids in this domain have been addressed.

Toward finding low-cost electrocatalysts with high catalytic properties to replace noble metals as high efficient electrocatalysts in electrochemical hydrogen evolution reaction (HER) of total water splitting plays a vital role to approach the green and sustainable energy supply. Here, we demonstrate the direct growth of novel copper phosphide coated with amorphous carbon, namely heterostructured a-C/Cu3P peapod nanowires from chemically synthesized copper nanowires (Cu NWs) followed by a chemical vapor phosphorization reaction (CVPR) process at a low temperature of 400 °C. The heterostructured a-C/Cu3P peapod nanowires exhibit a superior electrocatalytic activity by a lower overpotential of 287 mV at a current density of 10 mA cm−2 with a low Tafel slope of 72 mV dec−1 and excellent stability over 1000 cycles. The superior electrocatalytic performance can be explained by the superior contact of the electrolyte with active sites on the heterostructured a-C/Cu3P due to the high surface area of peapod nanowire structure covered by defective edges of graphene with the encapsulated amorphous carbon layer, which can tremendously enhance electrical conductivity at the surface.

In this study, white light is generated from the combination of BaMgAl10O17:Mn2+ (BAM) green phosphor and colloidal red CdSe/ZnS quantum dots (QDs) via two different solid and hybrid type geometries. Problem of aggregation in solid type device is discussed in details and motivates us to move towards the fabrication of hybrid type device structure. The photoluminescence (PL) characterization was used to record the excitation and emission spectra of BAM and QDs materials. The size of CdSe/ZnS QDs was confirmed by transmission electron microscopy technique. The CdSe/ZnS QDs owned high quantum yield (> 50%) and contributed to fabrication of high luminous efficiency of white light emitting diodes (WLEDs). The hybrid-type WLED showed 98% lm/W with outstanding color gamut values with a National Television System Committee (NTSC) value of 138% and Rec.2020 value of 105%. Moreover, the hybrid type device structure shows only 5% attenuation in luminous efficiency after 500 h of storage which maintains a great optical property.

Aluminum-sulfur batteries (ASBs) have attracted substantial interest due to their high theoretical specific energy density, low cost, and environmental friendliness, while the traditional sulfur cathode and ionic liquid have very fast capacity decay, limiting cycling performance because of the sluggishly electrochemical reaction and side reactions with the electrolyte. Herein, we demonstrate, for the first time, excellent rechargeable aluminum-selenium batteries (ASeBs) using a new deep eutectic solvent, thiourea-AlCl

In this work, the discovery of an abnormal p-type conductivity in SnSe2 thin films synthesized by a plasma-assisted chemical vapor reaction (PACVR) at a low temperature as low as 150 °C was reported. Due to a thermodynamically driven mechanism, three distinct phases including homogeneous SnSe2 and SnSe as well as a SnSe2/SnSe heterostructure were demonstrated. The SnSe2 homogeneous film was prepared by the PACVR from a thin Sn prelayer at a high substrate temperature on a glass substrate. The SnSe homogeneous film was prepared at a low temperature on a mica substrate regardless of the Sn prelayer thickness. Furthermore, the SnSe2/SnSe heterostructure film was prepared from a thick Sn prelayer on the glass substrate. All of the phases exhibit p-type conducting behavior because of hydrogen doping at the vapor–solid reaction interface during the PACVR. Furthermore, the first experimental evidence of intrinsic thermal conductivities of SnSe2 and SnSe thin film of 2.15 W/(m K) and 0.18 W/(m K), respectively, together with an interfacial thermal conductance of 11.32 MW m−2 K−1 in between, was measured by Raman scattering behaviors. The low thermal conductivity make PACVR-synthesized SnSe2-based thin films feasible for thermoelectric applications. In particular, the SnSe2/SnSe heterostructure is the optimized phase for use in thermoelectric generators owing to not only its low thermal conductivity but also the strong accumulation of holes and phonons near the surface.

Here, we demonstrate the successful synthesis of (1T/2H) MoS2/α-MoO3 heterostructured nanoflowers at a low temperature of 200 °C by a one-step hydrothermal method. By tuning the reaction time under the influence of thiourea and hydrazine hydrate, we established a complete phase-engineered MoS2 with 1T and 2H phases on the surface of α-MoO3. Active sites associated with the phase-engineered (1T/2H) MoS2/α-MoO3 hybrid nanoflowers enable them to exhibit dual roles as a superior dye adsorbent and an electrocatalyst towards the hydrogen evolution reaction. The 2H-rich (1T/2H) MoS2/α-MoO3 hybrid heterostructured nanoflowers prepared at 16 h achieved a high surface area of 37.97 m2 g−1, and 97% of the RhB dye with an initial concentration of 47.9 mg L−1 was removed within 10 min through the adsorption process, which is the highest known removal efficiency reported in the literature. As a hydrogen evolution reaction (HER) electrocatalyst in acidic solution, the 1T-rich (1T/2H) MoS2/α-MoO3 hybrid heterostructured nanoflowers prepared at 12 h exhibited a highly efficient catalytic activity by achieving a low overpotential of 232 mV at a current density of 10 mA cm−2, which is comparable to those of previously reported HER catalysts based on MoS2. Moreover, this sample reached a low Tafel slope of 81 mV dec−1 and was stable when operated for more than 1000 cycles.

An inductively coupled plasma (ICP) process was used to synthesize transition metal dichalcogenides (TMDs) through a plasma-assisted selenization process of metal oxide (MOx) at a temperature as low as 250 °C. In comparison with other CVD processes, the use of ICP facilitates the decomposition of the precursors at low temperatures. Therefore, the temperature required for the formation of TMDs can be drastically reduced. WSe2 was chosen as a model material system due to its technological importance as a p-type inorganic semiconductor with an excellent hole mobility. Large-area synthesis of WSe2 on polyimide (30 × 40 cm2) flexible substrates and 8 in. silicon wafers with good uniformity was demonstrated at the formation temperature of 250 °C confirmed by Raman and X-ray photoelectron (XPS) spectroscopy. Furthermore, by controlling different H2/N2 ratios, hybrid WOx/WSe2 films can be formed at the formation temperature of 250 °C confirmed by TEM and XPS. Remarkably, hybrid films composed of partially reduced...

Copper nanowire networks (NWs) coated with a graphene layer through a carbon-enclosed chemical vapor deposition technique at a low temperature of 400 °C with a low sheet resistance of 23.2 Ω sq−1 and a high transmittance of 83.4%, which is comparable to the typical values of tin-doped indium oxide (ITO), as a transparent conducting electrode were demonstrated. The graphene-coated copper NW networks retain a low sheet resistance of less than 25 Ω sq−1 even after annealing at a temperature of 240 °C in a pure oxygen environment for 1 h, while a sheet resistance less than 100 Ω sq−1 can still be maintained in natural sea water, and acidic and basic solutions. Their highly stable features in harsh environments make these graphene-coated copper nanowire networks suitable as a catalyst toward high-efficiency hydrogen evolution reactions (HERs) with a low overpotential of 252 mV at 10 mA Cm−2 and a low Tafel slope of 67 mV dec−1. The non-corrosive and anti-oxidant graphene-coated copper nanowire networks could be used as an alternative transparent conducting electrode in harsh environments, such as in tandem photocatalytic water splitting.

Organometal halide perovskite materials have triggered enormous attention for a wide range of high-performance optoelectronic devices. However, their stability and toxicity are major bottleneck challenges for practical applications. Substituting toxic heavy metal, that is, lead (Pb), with other environmentally benign elements, for example, tin (Sn), could be a potential solution to address the toxicity issue. Nevertheless, even worse stability of Sn-based perovskite material than Pb-based perovskite poses a great challenge for further device fabrication. In this work, for the first time, three-dimensional CH3NH3SnI3 perovskite nanowire arrays were fabricated in nanoengineering templates, which can address nanowire integration and stability issues at the same time. Also, nanowire photodetectors have been fabricated and characterized. Intriguingly, it was discovered that as the nanowires are embedded in mechanically and chemically robust templates, the material decay process has been dramatically slowed dow...

Since prevention methods of type-II diabetes and knowledge of prediabetes are lacking, the development of sensitive and accurate glucose sensors with an ultralow detection limit is imperative. In this work, the enzyme-free glucose sensor based on three-dimensional (3D) hierarchical Ni microflowers with a Ni(OH)2 coating layer has been demonstrated in a simple one-step chemical reaction at a low temperature of 80 °C. The as-synthesized materials were characterized by several analytical and spectroscopic techniques. In addition, the thin Ni(OH)2 layer formed at the surface of the Ni microflower was evidenced by Raman, HRTEM, and XPS, which is the key factor to achieve highly sensitive enzyme-free glucose sensors based on low-cost materials such as copper, nickel, and their oxide and hydroxide. Moreover, our modified electrode exhibits an outstanding detection limit as low as 2.4 nM with an ultrahigh sensitivity of 2392 μA mM–1 cm–2, which is attributed to not only the increased surface area due to the contr...

Because of tunable bandgap and high carrier mobility, ternary III-V nanowires (NWs) have demonstrated enormous potential for advanced applications. However, the synthesis of large-scale and highly-crystalline InxGa1−xSb NWs is still a challenge. Here, we achieve high-density and crystalline stoichiometric InxGa1−xSb (0.09 -orientation via chemical vapor deposition. The as-prepared NWs show excellent electrical and optoelectronic characteristics, including the high hole mobility (i.e. 463 cm2 V−1 s−1 for In0.09Ga0.91Sb NWs) as well as broadband and ultrafast photoresponse over the visible and infrared optical communication region (1550 nm). Specifically, the In0.28Ga0.72Sb NW device yields efficient rise and decay times down to 38 and 53 μs, respectively, along with the responsivity of 6000 A W−1 and external quantum efficiency of 4.8 × 106 % towards 1550 nm regime. High-performance NW parallel-arrayed devices can also be fabricated to illustrate their large-scale device integrability for next-generation, ultrafast, high-responsivity and broadband photodetectors., The application of ternary nanowires (NWs) in optoelectronics has been hindered by difficulties in producing high quality NWs on silicon substrates. Here, the authors report on InxGa1-xSb NWs exhibiting simultaneously high hole mobility, responsivity, and fast response times in the infrared regime.

In this work, a high-performance room temperature NO2 chemoresistive gas sensor is fabricated using a MoS2/ZnO nanohybrid. The nanohybrid is synthesized by drop-casting liquid exfoliated MoS2 nanosheets on ZnO nanorods. The uniform network-like distribution of MoS2 nanosheets on the nanorods is confirmed by various characterization techniques. Under UV-activation, the nanohybrid sensor exhibits remarkable responses of 91% and 2310% at 5 and 500 ppb NO2, respectively. In addition, full recovery to the base resistance is observed in each sensing cycle. The low concentration sensitivity is 0.135 ppb−1 and the lowest detection limit is estimated to be around 0.2 ppb. These two values are superior when compared with other reports. The adsorption/desorption kinetics has been studied in detail using the Langmuir adsorption model. The saturated response, the adsorption, and the desorption constant are determined to be 2744%, 3.52 × 10–5 ppb−1 s−1, and 3.50 × 10–3 s−1, respectively. The outstanding performance of the sensor can be attributed to the synergetic effects of MoS2 and ZnO including creation of abundant adsorption sites and fast charge carrier migration.

The necessity for new sources for greener and cleaner energy production to replace the existing ones has been increasingly growing in recent years. Of those new sources, the hydrogen evolution reaction has a large potential. In this work, for the first time, MoSe2 /Mo core-shell 3D-hierarchical nanostructures are created, which are derived from the Mo 3D-hierarchical nanostructures through a low-temperature plasma-assisted selenization process with controlled shapes grown by a glancing angle deposition system.