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Sorbents utilizing organic molecules as Cs+-selective ionophores have increasingly gained attention over the years as the need for stable and reusable materials became ever more apparent with the poor performance of inorganic sorbents in acidic and alkaline aqueous environments. Aside from this, organic molecules offer a great degree of flexibility in terms of structure, function, and performance which can be harnessed for sorbent development. As such, various kinds of organic ligands have been employed for sorbent preparation, which include macrocycles like calixarenes and crown ethers, and acyclic molecules like tetraphenylborate and resorcinol formaldehyde. In this review, organic-based sorbents and ligands for Cs+ are described and compared, and the mechanisms underlying their efficacy for Cs+ sequestration are discussed. Improvements to ligand and sorbent development are proposed to address issues on adsorption selectivity, capacity, and material reusability. Moreover, a platform for the preparation of stimuli-responsive ligands and sorbents is presented.

Phosphorous doping augments HER and OER activity of Fe2O3/ZnO nanotubes.

A hybrid smart window exhibiting dual chromic response properties based on an ionene/polymer material is successfully engineered. Thermochromic poly(N-isopropylacrylamide) is integrated with an electrochromic viologen-tethered ionene, also acting as an electrolyte, to produce a smart window that can adaptively control solar visible light transmittance in response to multiple stimuli. This new blend allows the formation of unique reversible optical states, namely, "clear", "amber", "cloudy", and "grainy" states, which are passively triggered by environmental temperature and actively induced by external potential or simultaneously by both. This hybrid material shows tunability in terms of its electrochemical and optical properties, switching kinetics, and coloration efficiency and can also achieve a nearly absolute zero-transmissive state. With the material's excellent solubility and film-forming ability, the smart device can be fabricated with much flexibility and ease. Finally, this device has an all-in-one layer configuration, creating a more compact and simplified design. With all these properties combined, the development of a next-generation multifunctional smart window device, which can efficiently control incoming solar light for energy-saving in buildings and also provide visual comfort, is possible.

In the hospitality sector, it is often believed that giving more power to customers (e.g., “the customer is king”) would enhance the service quality, customer satisfaction, and organizational performance. However, it can cause a backlash by excessively elevating the level of the customers’ perceived power, which could result in their power abuse against the employees. Based on the organizational support theory, this research argues that balancing the level of power between the customers and the employees (vs. shifting the power to the customers) can be more effective for improving the perceptions of both the current and the potential employees. The argument is empirically supported by the findings from three studies, which showed that adopting a power-balancing message positively affects the current employees’ perceived organizational support and motivates them to feel obliged to give back to the organization and also potential job applicants’ organizational attraction and the job pursuit intention.

Zinc oxide (ZnO) nanostructures/bacteria (Escherichia coli, E. coli) composite material is successfully prepared via carbonization process. Morphological and electrochemical properties of nanostructure were studied as function of concentration of bacteria solution. Morphological properties of the composite material were investigated by scanning electron microscopy (SEM) and Brunauer–Emmett–Teller (BET). The new approach of high-performance electrodes based on carbonization prepared from precursor and reductant of ZnO and bacteria resources. The ZnO nanostructures were reacted with the bacteria to introduce carbon (C) and nitrogen (N) for better electrochemical performance and an increased surface area. The bacteria doped ZnO electrode exhibited significantly enhanced specific capacitance (41 F g−1) at a discharge current density of 0.5 A g−1, and cycling stability of 55% retention after 5000 cycles. Therefore, the bacteria as electrical dopant gave higher specific capacitance and cycle stability to the other metal oxide which could be a potential candidate in commercial applications of supercapacitors.

Designing an active and reliable electrocatalyst is the urgent need for the desirable improvement in direct methanol fuel cells (DMFCs). In recent time, binary metal oxides have shown much attention as possible electrocatalysts for the future DMFCs. Herein, we have reported direct growth of 3D-CuCo2O4 on Nickel foam (NF) by hydrothermal route for electrochemical methanol oxidation. The electrochemical performance was examined by cyclic voltammetry (CV), chronoamperommetry (CA) and electrochemical impedance spectroscopy (EIS) techniques. Electrochemical analysis of 3D-CuCo2O4 exhibits high current density of 112 A g−1 at scan rate of 10 mV s−1 and retains 91% of initial current density after 1000 C V cycles. The high electrocatalytic activity of mesoporous 3D-CuCo2O4 is mainly ascribed to the synergetic effect of bimetallic element (Cu and Co), high surface area and enhanced charge-transfer because of direct growth of catalyst on NF. The present synthesis strategy and use of spinel oxides can offer promising feature for the development of non-precious catalysts for DMFCs.

The biogenic synthesis of copper oxide nanoparticles (CuO NPs) from the leaf extract of Alpinia zerumbet was investigated in this protocol. The basic nature of A. zerumbet leaf extract helps in CuO NPs synthesis. The catalytic activity of A. zerumbet-fabricated CuO NPs is explored in water at room temperature only in the presence of NaPTS hydrotrope. The green catalytic protocol is investigated via synthesis of 1,8-dioxooctahydroxanthene. The biogenic leaf extract fabricated CuO NPs are efficiently reactive, stable and recyclable in aqueous solution of sodium p-toluenesulfonate (NaPTS) hydrotrope. CuO/NaPTS proved to be the best catalytic system as synergistic nanotrope in terms of yield and time of reaction in water at room temperature. The green synthetic approach of CuO NPs, greener medium, easy workup and proficient recyclability are advantages in the said protocol. This is first time report of catalytic activity of biogenic CuO NPs in water at room temperature in the presence of NaPTS.

In this study, an electrocatalyticaly inactive ZnO@Ni foam photoelectrode was modified with heteroatom doped graphitic carbon to achieve enhanced photoelectrochemical (PEC) water splitting performance. The O, S and N doped graphitic carbon was simultaneously deposited with ZnO on Ni foam substrate under hydrothermal deposition. One dimensional ZnO nanorods with flower-like graphitic carbon on their surface were obtained on the Ni foam substrate, which was directly used as photoelectrode to derive photoelectrochemical water splitting under solar light irradiation. The pristine ZnO@NF exhibit unattractive PEC performance evidenced by the high overpotential required for the oxygen evolution reaction (OER) couple of water splitting reaction (398 mV vs. RHE). The carbon modified ZnO–C@NF photoelectrode lowers the overpotential required to 317 mV. This enhancement was attributed to the carbon modification which serves as both active site and photoelectron reservoir; facilitating the sluggish kinetics of OER couple reaction and promoting separation of photogenerated charge carriers.

The involvement of CO2 as a renewable and abundant feedstock toward a carbon balanced future has led to production of several value-added products. The primary focus in the current effort is to ass...

Re-purposing of sulfur, a petroleum industry by-product, will not only address safety issue of its storage but also advance its valorization. Herein, sulfur was directly copolymerized with 2-carbox...

Catalytic hydrolysis of chemical hydrides with the use of NaBH4 is a safe and effective way to provide hydrogen fuel for new energy vehicles and portable electronic devices. Herein we developed a Cu and Mo promoted Co hierarchical composites (Co1−xCuxMoO4) for hydrolysis of NaBH4 via an easy synthesis route. FESEM analysis depicts that the morphology of Co1−xCuxMoO4 hierarchical composites varied significantly from irregular microsphere to marigold microsphere to rose like morphology with the increase in Cu (x) ratio with respect to Co (1 − x). Flower-like morphological architecture and crystal configuration empower the supported catalyst to exhibit a remarkable catalytic activity and outstanding catalytic activity was obtained for marigold-like Co0.9Cu0.1MoO4 catalyst with an H2 generation rate of 1005.7 mL min−1 g−1, which confirms existence of synergistic effect between Co, Cu and Mo. Lower loading of Cu in Co1−xCuxMoO4 supported the active sites of Co to increase its catalytic activity. Additionally, the catalyst exhibits good recyclability after five successive runs of hydrolytic reaction, making it a robust catalyst for hydrolysis of NaBH4 and could be considered as a potential catalyst for portable hydrogen fuel systems.

South Korean universities have been facing student shortages to sustain their growth due to its severe population decline. The Korean government has since introduced policies to attract more international students to the country. The present study examined the prestige-seeking tendencies of international students in Korea and their influence on students’ satisfaction levels. The five dimensions of prestige-seeking behavior were adopted to help explain students’ satisfaction levels. Research samples were current and former international students in Korea. The findings reveal the quality of the education did not contribute directly to the students’ overall satisfaction level. Instead, it was hedonic elements that affected satisfaction. Moreover, status, snob, and bandwagon effects contributed significantly to the quality and hedonic motives.

The soaring demand and future supply risk for cobalt (Co) necessitate more efficient adsorbents for its recycling from electronic wastes, as a cheaper and less hazardous option for its production. Herein, a magnetic adsorbent covalently tethered with 5-hydroxypicolinic acid (HPCA) as Co(II) ligand was developed. The magnetic component (Fe

Design and construction of low-cost electrocatalysts with high catalytic activity and long-term stability is a challenging task in the field of catalysis. Metal-organic frameworks (MOF) are promising candidates as precursor materials in the development of highly efficient electrocatalysts for energy conversion and storage applications. This review starts with a summary of basic concepts and key evaluation parameters involved in the electrochemical water-splitting reaction. Then different synthesis approaches reported for the cobalt-based Zeolitic imidazolate framework (ZIF-67) and its derivatives are critically reviewed. Additionally, several strategies employed to enhance the electrocatalytic activity and stability of ZIF-67 based electrocatalysts are discussed in detail. The present review provides a succinct insight into the ZIF-67 and its derivatives (oxides, hydroxides, sulfides, selenides, phosphide, nitrides, telluride, heteroatom/metal-doped carbon, noble metal-supported ZIF-67 derivatives) reported for OER, HER, and overall water splitting applications. Finally, this review concludes with the associated challenges and our perspectives on developing the best economic, durable electrocatalytic materials. This article is protected by copyright. All rights reserved.

The discovery of the lubricant infused surface (LIS) embarked a promising approach on the active surface applications. Demonstrated here is an intricately designed multifunctional film influenced by bottom-up approach, utilizing the underlying features of the compounding materials to provide greater functionalities and opportunities for various applications. Through facile fabrication method, a porous film was generated by incorporating ZnO nanoparticle as a porogen onto PDVF polymer prior casting followed by simple acid washing for the removal of ZnO. Wax was used to lubricate the porous thin film; the design was inspired by the advantageous property of the wax that will enhance surface wetting properties, exhibiting the surface with thermal responsiveness, anticorrosion protection and robust structure. By taking advantage onto the lubricant’s rheological property, droplet motion control in response with the temperature variation was explored. Surface responses on different kinds of liquids were also studied. The multifunctional film manifested anticorrosion protection, which is supported by electrochemical measurement technique. The film’s stability was explored through exposure on harsh condition that successfully preserve its robust architecture.

A novel zwitterionic lithium-benzotriazole sulfobetaine is fabricated by grafting 1,3– propanesultone onto benzotriazole and then lithiating it. The resultant lithium-benzotriazole-sulfobetaine additive is used as an electrolyte additive in lithium ion batteries in 1 M LiPF6 (ethylene carbonate/dimethyl carbonate = 1:1). The electrolytes with the lithium-benzotriazole sulfobetaine shows higher ionic conductivities (2.18 × 10−2 S cm−1) compared to the bare electrolyte (1.07 × 10−2 S cm−1) and greater electrochemical stability (anodic limit at ~5.5 V vs. Li/Li+) than the pure electrolyte (anodic limit at ~4.6 V vs. Li/Li+). The discharge capacity of the lithium cobalt oxide/graphite cells is improved at higher C-rates with the addition of lithium-benzotriazole sulfobetaine due to increased ionic conductivity. The lithium cobalt oxide/graphite cells with the lithium-benzotriazole sulfobetaine additive also show stable cycling performance. These findings warrant the use of lithium-benzotriazole sulfobetaine as an electrolyte additive in lithium ion batteries.

Several types of ionic liquids (ILs) performance towards dimethyl carbonate (DMC) synthesis using cheap reactant (methanol) and waste CO2 which is abundantly available in the environment are discussed. We synthesized ILs with cheap raw materials such as ethylene glycol. The main aim of this study is to synthesize efficient catalysts for the production of profitable fuel additives. ILs show high thermal stability, less viscosity, and low vapor pressure. In addition, some ILs have high CO2 absorption capacity due to moderate acid-base properties. These ILs reversibly capture more CO2 which is more efficient towards mass transport of methanol at optimum reaction conditions which enhance the DMC yield. This catalytic system is easily reusable for several reactions without decreased performance under the same reaction conditions. These reaction conditions had an effect on the synthesis of DMC. Temperature, pressure, IL loading, and IL/DMAP ratio were fine tuned. We propose a mechanism which the reaction may follow. The synthesized ILs required moderate reaction conditions and reduce waste gases (CO2) from the environments as they have high CO2 absorption capacity compared to the metal oxide catalyst. Therefore, this catalytic system helps and gives new direction to synthesize new catalyst for other application.

The present study describes the hydrogen production as a future energy source via hydrolysis of NaBH4 catalyzed by urchin-like CuCo2O4 spinel catalyst prepared by urea-assisted hydrothermal synthesis method. The as-synthesized copper–cobalt double hydroxide precursor and the resultant CuCo2O4 spinel were characterized by using various analytical, spectroscopic and microscopic techniques in order to understand their physiochemical and morphological aspects. The detail characterization results confirmed the successful formation of CuCo2O4 spinel phase with urchin-like morphology. The CuCo2O4 spinel catalyst was then tested for its application in hydrogen generation from NaBH4 hydrolysis by performing the reaction using 10 wt% of CuCo2O4 spinel catalyst and 0.5 g NaBH4 at room temperature. The CuCo2O4 spinel catalyst with tailored architecture displayed high catalytic activity with H2 generation rate of 1370 mL min−1 g−1 (1438 mL in 21 min). Major factors affecting the hydrolysis of NaBH4 reaction such as catalyst loading, NaOH concentration and temperature variation was also studied and discussed in detail. Correspondingly, the low activation energy of 22 kJ mol−1 was obtained from the Arrhenius plot and kinetic studies revealed that the hydrolysis of NaBH4 followed first order kinetics. Further, recyclability study of CuCo2O4 spinel catalyst was also performed which displayed good catalytic activity and stability even after five successive recycles. Characterization data of reused catalyst revealed that physiochemical properties of fresh CuCo2O4 spinel catalyst were well-preserved in the reused catalyst as well. Therefore, nanostructured CuCo2O4 spinel can be demonstrated as one of the most efficient, cost effective bimetallic spinel catalyst so far for application in the hydrogen generation.

Glycerol based symmetrical cations with different anions accommodated ionic liquids (ILs) was found to be the most prominent catalyst system to produce cyclic carbonate (CC) from carbon dioxide (CO2) and propylene oxide (PO) for the first time. The synthesized ILs was analyzed by different spectroscopic technique, the thermal stability of ILs was analyzed by TGA, DSC. The mole ratio of IL/DBU gives a positive effect towards the product yield and selectivity. The best catalytic activity and long-term durability of ILs could be due to the synergistic combination of cation and anion makes an ideal catalyst for title reaction. The effect of ILs loading, temperature, pressure, and time on the production of cyclic carbonate was also investigated to determine the best reaction conditions (final 2 MPa CO2 pressure, 4 h, and 110 °C) the propylene carbonate (PC) selectivity and yield was 98.2 and 91.9%. Moreover, based on TGA and FT-IR analysis the catalyst system could be reusable up to four times (16 h) with no change in catalyst performance and product selectivity. In addition, the probable mechanism of this reaction was also proposed with the help of 13C NMR analysis.

Carbon dioxide (CO2) mitigation via utilization can be a potential solution to global warming issues such as increasing CO2 concentration. In this study, we present the synthesis and characterisation of 3-(2-hydroxyethyl)-1-vinyl-1H-imidazol-3-ium chloride [EvimOH][Cl] and 3-(2-hydroxyethyl)-1-vinyl-1H-imidazol-3-ium sulphate [EvimOH][HSO4] ionic liquids for cycloaddition reactions of CO2 and epoxides into cyclic carbonates. The synthesized ionic liquids were characterized by FT-IR, 1H- and 13C-NMR spectroscopic methods. Also, we have analysed the physical properties of ionic liquids by using TGA and DTA. Further, the CO2 consumption was done by developing a binary catalytic system with bases such as DBU, TEA, DIPEA, piperidine, pyrrolidine, aniline. The developed binary ([EvimOH][Cl]/base) catalytic system exhibited the excellent catalytic activity of 99.8% conversion and ≥99% selectivity under mild reaction conditions without the aid of solvent and metal co-catalysts. Furthermore, the results show that the improved activity from the binary system is due to synergistic effect among −OH functional group from the cation, reactive acidic C(2)-H in the imidazolium ring and amine containing bases which promote the CO2 absorption. Also, a plausible mechanism of cyclic carbonate formation and kinetic study in the presence of binary catalytic system was demonstrated.

Carbon-doping in the crystal structure of ZnO has been proven to promote visible light induced photocatalytic activity. However, experimental procedures reported in literature to date for the fabrication of C-doped ZnO generally follow cumbersome steps and environmentally unfriendly techniques. In this study, we present a simple, relatively “green” and adaptable two-step synthesis using electrospinning and calcination techniques for the fabrication of C-doped ZnO nanofiber photocatalyst. Extensive characterization of the as-prepared nanofiber photocatalysts was made by XRD, XPS, FE-SEM, FE-TEM, EDS, N2 adsorption, TGA, FT-IR, LSV and EIS analysis techniques. Depending on the calcination temperature, the crystallinity of the ZnO nanoparticles and amount of the polymer matrix on the nanofibers differ, which in turn tune the photocatalytic performance. Crystal structure and chemical state analysis confirm the C-doping and introduction of new energy level (Zn C) in the ZnO crystal. Photoelectrochemical analysis proved the enhanced photocurrent response and reduced charge carrier recombination in the C-doped ZnO. The as-prepared photocatalyst exhibited high degradation efficiency (96% in 30 min) for the solar light mediated photodegradation of Methylene blue dye. The fibrous nature of the photocatalyst, with Carbon matrix wrapping around it, alleviates the recovery of the as-prepared photocatalyst from the reaction mixture and ensures its recyclability and protection against photo-corrosion. Considering the scalability and easiness of the experimental procedure, together with the enhanced photocatalytic activity and recyclability of the photocatalyst prepared, we believe this study open doors for the fabrication of high-performance photocatalytic materials at large scale.

In this study we fabricated a hollow carbon nanofiber (CNF) via a facile dual nozzle electrospinning process and directly used as low-cost and environmental friendly carbon source material, which were incorporated to NiCo2O4 (NCO). We designed a hybrid nanocomposite based on synergistic mixture of hollow structure CNF and spinel NCO, with 3D dandelion like morphology, hierarchical mesoporous surface, high specific surface area, and directly grown onto the surface of nickel foam substrate. We modified the structural properties of hybrid NCO–CNF nanocomposite in aim to improve its overall electrochemical performance towards supercapacitor application. In here, we fabricated our hollow CNF using dual concentric nozzle electrospinning method, comprising of poly (vinyl pyrrolidone) (PVP) as soluble core and polyacrylonitrile (PAN) as shell. It was essential in our study to fully leach out the PVP to obtain a hollow structure: this hollow structure of CNF provided a conductive network that guaranteed the high speed movement of electron/electrolyte. Furthermore, the overall specific capacitance and energy density of the hybrid NCO–CNF electrode were remarkably boost up due to the derivation of both electric double layer capacitance and pseudocapacitance characteristics based on the synergistic mixture of graphitic carbon and transition metal oxides. The fabricated binder-free hybrid NCO–CNF electrode displayed efficient charge transfer and achieved outstanding specific capacitance and energy density as high as 1188.19 F g−1 and 37.23 W h kg−1, respectively, even at high current density of 50 A g−1.

The development of cost-effective electrocatalyst with high activity and stability during the oxygen evolution reaction (OER) is a prerequisite for commercialization of several energy storage/generation technologies. Herein, porous carbon materials doped with Co, nitrogen, and sulfur were synthesized through the carbonization of a mixture containing [1-vinylimidazolium] [HSO4] ionic liquid (IL) and CoCl2 under an inert atmosphere. The structural diversity of ionic liquids offered control over the structure and properties of the carbon materials at the molecular level. The protic ionic liquid used acted as a soft template and a source of heteroatoms. A change in the mass ratio of cobalt chloride to ionic liquids resulted in materials with three different morphologies with/without S and N. The resulting Co10-NS-C material exhibited considerably enhanced catalytic performance toward the OER, which compared favorably to that of state-of-the-art Ru-based catalysts. Moreover, the Co10-NS-C catalyst demonstrated...

With the aim to develop an eco-friendly, efficient and stable photocatalyst, the present work reports the synthesis of Ag3PO4/LaCO3OH (AP/LC) heterojunction photocatalysts. Different weight ratios of AP/(x wt% LC) were tested to find the best composition for superior photocatalytic activity for dye pollutant degradation. AP/LC (20 wt%) revealed a superior photocatalytic activity. Hence it was selected for further analyses. Furthermore, we investigated the influence of distilled water: tetrahydrofuran (DW:TF) solvent system on the morphology as well as photocatalytic activities of AP/LC (20%) heterojunction. FESEM analysis shows that the morphology of AP/LC heterojunctions varied significantly with TF:DW ratio. Sphere-shaped like nanoparticles of LC transformed into nanowires to make intimate contact with AP polyhedras. The increase of TF with respect to DW results increase in the width of wire-like dimension of LC causes loose intimate contact within AP/LC heterojunction. The photocatalytic performance of AP/LC heterojunctions were tested against degradation of toxic phenol contaminant, and the outstanding photocatalytic activity was noticed for the AP/LC-2 photocatalyst (~99% degradation in 120 min) with a rate constant, k of 1.281 × 10−2 min−1. The improved photocatalytic performance can be attributed to the uniform decoration of LC nanowires on the AP microstructure which leads to intimate interface within the heterojunction and effective charge separation. The recyclability of the AP/LC-2 photocatalysts was evaluated via replicated photocatalytic reaction trials.

Current research on ZnFe2O4-based adsorbents rely mainly on its surface charge to remove Congo red (CR). However, the weak charge of ZnFe2O4 due its normal spinel structure makes this approach inefficient as evident from its low activity. Considering the potential of ZnFe2O4 as a low cost nontoxic adsorbent, it is important to improve its activity. Herein, we present an in-situ prepared 1-D ZnO-ZnFe2O4 with a heterojunction which adsorbs CR chemically instead of the generic physisorption. While its 1-D structure allows very low adsorbent loading to be employed. Together, these two unique properties make 1-D ZnO-ZnFe2O4 ˜3.3x more effective at treating CR effluent than reported ZnFe2O4-based adsorbents. The chemisorption reaction involves chelating/bridging bidentate bonding between sulfonic groups on CR and ZnO-ZnFe2O4 heterojunction. Its potency is regulated by the ZnO content of the composite which suggest a synergistic effect between the metal oxides phases. Interestingly, spent 1-D ZnO-ZnFe2O4 can be regenerated in NaOH solution and retains ˜75% of its adsorption capacity even after repeated use. These findings provide key insights into how interfacial interactions in mixed metal oxide composites and their morphology affect dye adsorption. This information may be useful to develop high performing adsorbents from metal oxides in general.