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The electrochemical water splitting into hydrogen and oxygen is the promising way for renewable hydrogen production as a carbon-neutral fuel, along with oxygen as a by-product. Herein, a novel nanoporous CoCu-layered double hydroxide (LDH) bifunctional electrocatalyst is fabricated by the hydrothermal method. The outstanding activity is mainly attributed to the incorporation of Cu2+ that promotes conductivity and enhances the electrochemical properties. As-prepared CoCu-LDH nanostructure works as efficient and stable water-splitting-electrolyzer and produces the voltage of 1.60 V at the current density of 10 mA cm−2, which is better than catalyst based on the combination of commercial IrO 2 and Pt/C. Due to high electrocatalytic performance, together with its low cost and natural abundance of LDHs, it is expected that CoCu LDH can act as a candidate catalyst in the commercial alkaline overall water splitting. • A novel nanoporous CoCu-LDH nanoplates are successfully prepared. • The electrocatalyst perform excellent activity and long-term stability towards HER and OER. • The incorporation of Copper ions promotes conductivity and stability. • The porous nanoplates morphology provides abundant active sites and promotes contact with the electrolyte. [ABSTRACT FROM AUTHOR]

High dielectric constant and ultra-low dielectric loss are important for electronic device applications of dielectrics. In this work, the novel ceramic BaNd 2 Ti 4 O 12 , synthesized via solid-state reaction, exhibits remarkable dielectric stability, with excellent dielectric properties (ε ′ = 117 and tan δ = 6.27 × 10−4, at 1 kHz) and high dielectric strength (E b = 260 kV/cm). By exploring its polarization behavior and loss mechanisms at low frequencies for the first time, we found that the sustained high dielectric constant is attributed to the synergy of defect dipole polarization and interface polarization, while the observed exponential increase of dielectric loss is primarily caused by the conduction loss, with a minor contribution from the anelastic relaxation loss. In the low-temperature range of 50∼350 °C, the relaxation behavior is governed by the aggregation and subsequent thermal ionization of the oxygen vacancies, whereas at temperatures above 350 °C, it is predominated by the long-range motion of the doubly ionized oxygen vacancies. These findings provide valuable insights for the potential electronic device applications of BaNd 2 Ti 4 O 12. [ABSTRACT FROM AUTHOR]

Sustainable induction of Electric vehicles (EV) adoption in developing countries requires a comprehensive policy and planning. Among several challenges, one of the biggest challenges is a sustainable charging station infrastructure integration to the existing weak distribution power network. Based on technological advancements, EV owners enjoy better milage in one charge. This has given a liberty to charge EVs as per the desire of user. There are two kinds of charging preferences, one is home charging and the other is fast charging. Both charging choices have distinct economic and technical aspects that need to be quantified in line with the available power infrastructure so as to develop a policy regulation. This study aims to quantitatively assess home charging, level 3 fast charging and their techno-economic aspects using social demographics of car owners. To analyze the demographics of local vehicle mobility practices in Pakistan, a comprehensive survey comprising online questionnaire was conducted. >100 car owners were surveyed about their daily driving practices to understand the driving distances and their preference of charging vehicles. The driving owners from distinct occupations ranging from cab drivers, job holders and businessmen participated in the survey. The survey facilitated to identify the demographics of the car owners which helped in conducting simulations and quantification analysis. Monte Carlo simulation was used for 1000 cars samples to estimate the level 1 and level 3 charging profiles in Python. In second step, HOMER Grid software was used to economically assess the impact of home charging and fast charging. It was revealed that charging choices have significant impact on the daily load profile of EVs. While having home charging, 59.9 % higher units are purchased from the grid. Whereas 65.5 NPC is increased for the project. On the other hand, the daily profile of preferred home charging is 61.4 % higher compared to the fast charging due to much concentrated charging impact during the limited time of the day. Results highlighted that Solar PV plays an important role for fast and home charging. Without solar PV charging stations will consume 60 % more grid units and 58 % higher Net present cost. The study concludes with a set of policy recommendations that must be taken into account to support the weak grid and lessen the EV charging impact on main utility. • This study aims to quantitatively assess home charging and level 3 charging preferences and their techno-economic aspects. • The proposed study was conducted in Pakistan where survey was conducted where car owners from major occupations participated. • The recorded responses were used to estimate the driving demographics and preferred charging preferences. • In the second step, HOMER Grid software was used to economically assess the impact of home charging and fast charging. • It was revealed that charging choices have a significant impact on the daily load profile of EVs. [ABSTRACT FROM AUTHOR]

Transition metal phosphides have promising applications in catalysis, sensors, environmental remediation, and energy storage due to their diverse crystal structures and physicochemical properties. In this study, using first principles calculations, we investigate the structural, electronic, mechanical, optical, and thermally conductive properties of transition metal tetraphosphides, TMP 4 (TM = V, Cr, Mo). The mechanic properties and phonon spectra prove that TMP 4 (TM = V, Cr, Mo) are mechanically and thermodynamically stable. The electronic structures calculated by HSE06 reveal that VP 4 is metallic, while CrP 4 and MoP 4 are direct bandgap semiconductors. Both CrP 4 and MoP 4 have very low carrier effective masses and much high carrier mobilities in the [ 100 ] direction. Moreover, CrP 4 and MoP 4 exhibit relatively high optical absorption coefficients and lattice thermal conductivities, promising them potential use as high-temperature solar-light-absorbing materials. [ABSTRACT FROM AUTHOR]

Zn 4 O(BO 2) 6 based on the [B 24 O 48 ] sodalite-cage structure fixed by the inside [Zn 4 O 13 ] clusters is expected to be a new class of solid-state lighting material with perfect thermal and mechanical stabilit y. Herein, in the current work, we have respectively introduced non-equivalent rare-earth cations Eu3+ and Pr3+ into Zn 4 O(BO 2) 6 host to design white and green emission materials by a novel solid-phase sintering method at lower temperatures. Zn 2 B 6 O 11 replacing B 2 O 3 or H 3 BO 3 as raw materials can effectively avoid the impure products caused by the uncontrollable volatilization of B 2 O 3 or H 3 BO 3. The newly designed light-emitting materials of Zn 4(1- x) O(BO 2) 6 : x Re3 + (Re Eu or Pr), including Zn 4 O(BO 2) 6 host, have good absorption capacity in the ultraviolet region. Under ultraviolet irradiation, Zn 4 O(BO 2) 6 , Zn 4(1- x) O(BO 2) 6 : x Eu3+and Zn 4(1- x) O(BO 2) 6 : x Pr3+ emit the blue, white and green lights, respectively. In addition, all these materials can effectively degrade methylene blue, in which Zn 4(1- x) O(BO 2) 6 : x Pr3+ has the highest efficiency. The luminescence and degradation mechanisms of Zn 4 O(BO 2) 6 , Zn 4(1- x) O(BO 2) 6 : x Eu3+and Zn 4(1- x) O(BO 2) 6 : x Pr3+ have been adequately explained by their electronic structures based on the first principle calculations. The current study confirms that the doping of Eu3+/Pr3+ in Zn 4 O(BO 2) 6 can broaden its applications as photoluminescent and photocatalytic materials. [ABSTRACT FROM AUTHOR]

Porous carbons have spurred tremendous interest as cutting-edge materials for diverse energy and environmental applications. To this end, hard and soft templating routes have developed various porous carbon-based materials with uniform and ordered porosities. Notwithstanding, the pores of carbons obtained via most of these preparation methods are vulnerable to blockage because their tunability is limited only to the micro-mesoscale size regime. This problem, in turn, makes the inner parts of such porous carbons inaccessible to the reactive species, thus hampering their community-scale adoption. To overcome this daunting challenge, emulsion-based approaches (i.e., emulsion polymerization, emulsion templating, and emulsion freeze drying) have turned out to be intriguing to endow the derived carbons with hierarchically-organized pores spanning over multiple-scale, large V p , and multidimensional transport pathways of particular interest. These attributes of such porous carbon materials have unfolded many prospects for broad-spectrum applications. This article systematically summarizes the synthetic progress of the emulsion-derived porous carbon-based NSs, particles, spheres, and monoliths. The applications section showcases their performance in energy storage (LIBs, LSBs, LOBs, ZABs, and electrodes for supercapacitors) and environmental remediation (CO 2 capture, dye adsorption, herbicide separation, and oil/organic solvent removal). Despite significant advancement, plenty of room is available to develop more promising new emulsion-derived porous carbons. Nonetheless, there is still a long way to go before materializing the dream of industrial-scale energy and environmental applications of such emulsion-derived porous carbons. [Display omitted] • Emulsion strategies appear exclusive to derive carbons having hierarchical pores. • Micro-/mesopores account for high surface areas with a more significant number of reaction sites. • Macropores expedite easier electron and mass infiltration and transport. • Emulsion-driven porous carbons display ample potential in batteries and supercapacitors. • Such materials are well-suited for many environmental applications. [ABSTRACT FROM AUTHOR]

This research describes the synthesis of a novel type of poly [cyclotriphosphazene-co-1,3,5-triol nitrobenzene] (PCTNB) microspheres with uniform size and diameter of more than 2 μm having well characterization. These microspheres are further used to wrap the CNTs by a facile route using template based non-covalent method to form PCTNB@CNTs composite. This composite is further well analyzed before it is subjected to pyrolysis. The direct carbonization of the PCTNB@CNTs is performed at 600 °C at a rate of 5 °C/min under N 2 atmosphere to render the N, P, O doped carbonized PCTNB@CNTs having enhanced electronic features to be applied as an ORR electrocatalysts in fuel cells accompanied by TEM, XPS, Raman, FT-IR, TGA and BET analyses. Here, we have designed a metal-free, N, P, O doped (C-PCTNB@CNTs) electro-catalyst which exhibit significantly high ORR performance in acidic PEM cells showing much higher onset potential of (0.94 V) and half-wave potential of (0.85 V) with electron transfer number ( n ) 3.9 at 0.4–0.7 V as compared to other non-metallic electro-catalysts. Thus, (C-PCTNB@CNTs) is a metal-free, methanol tolerant carbon-based ORR catalyst, and it opens up new avenues for clean energy generation for affordable and durable fuel cells. [ABSTRACT FROM AUTHOR]