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The few intuitive challenges are the high clean energy demand, the dire need for sustainable development, and low carbon footprints. Thereby, the wastewater rich in urea from sanitary units, and industries are subjected to produce green energy as a source for hydrogen through waste water-splitting. Thus, anodic reaction in electrochemical hydrogen production is the most widely promoted towards oxygen evolution reaction (OER) and urea oxidation reaction (UOR). However, both possess sluggish kinetics which need to be improved. Therefore, the development of novel materials that can meet the demands of both reaction mechanisms is highly required. Herein, Fe 2 P 2 O 7 -based composite grown on the conductive substrate can effectively enhance the electrical transportation of ions during electrocatalytic activity. The experimental and theoretical investigations are adopted to get a comprehensive insight and understanding of the catalytic nature of the as-prepared samples. Compared with other as-synthesized materials, Fe 2 P 2 O 7 exhibits splendid performance with a low onset potential of 1.482 and 1.317 V (vs RHE) to obtain a current density of 10 mA/cm2 towards the OER and UOR process, respectively. The low Tafel slope and high turnover frequency offer low resistance during charge transfer. Additionally, greater ECSA and roughness factors enrich the attributes of Fe 2 P 2 O 7 and offer more active sites for reaction to be held, producing a higher amount of gas bubbles. Hence, improved electrical conductivity, low charge transfer resistance, more electrochemical active surface area, and impressive durability reconfirm the Fe 2 P 2 O 7 as an effective catalyst. • Fe 2 P 2 O 7 , Co 2 P 2 O 7 , and Ni 2 P 2 O 7 materials were prepared using hydrothermal approach. • Fe 2 P 2 O 7 showed the best electrocatalyst activity in urea-assisted water splitting. • DFT showed a high DOS over fermi-level, increasing Fe2P2O7's catalytic properties. • Metal-P 2 O 7 have the ability for electrochemical energy conversion and storage. [ABSTRACT FROM AUTHOR]

Electrochemical energy conversion (via water splitting) and storage (via supercapacitors) are emerging strategies for developing the renewable energy sector; nevertheless, the hunt for low-cost and effective electrode material is a bottleneck issue. Herein, a bimetallic manganese nickel hydroxide was electrodeposited on Ni-foam without polymeric binder, followed by calcination to reveal its oxide configuration. As prepared, manganese nickel hydroxide (MnNi-hydroxide) displayed low Oxygen evolution reaction (OER) and Hydrogen evolution reaction (HER) overpotentials of 231 mV and 327 mV at 10 mA/cm2 during electrochemical water splitting, along with a superior turnover frequency of 0.12 sec−1 and 0.056 sec−1, respectively. Theoretical investigations revealed an increase in MnNi-hydroxide activity due to synergistic electronic interaction between Mn and Ni. Further, the MnNi-hydroxide, having high specific capacitances of 1174 mF/cm2 at 2 mV/s and 308 mF/cm2 at 1 mA/cm2, demonstrated a retention capacity of 98.9% over 5000 cycles. [Display omitted] • A bimetallic Mn-Ni hydroxide was electrodeposited on Ni-foam without polymeric binder. • Mn-Ni hydroxide displayed low OER and HER overpotentials of 231 mV and 327 mV at 10 mA/cm2. • This material also showed high specific capacitances of 1174 mF/cm2 at 2 mV/s and 308 mF/cm2 at 1 mA/cm2. • The synergistic interaction between Mn and Ni is a crucial factor in the efficient bifunctional activity. [ABSTRACT FROM AUTHOR]

• Indirect evaporative cooler and Maisotsenko cycle hybrid design proposed. • Optimal intermediate temperature to minimize total area depends on ambient. • 10–18 % smaller overall area compared to M−cycle. • Optimal recirculation ratio lower (0.1 to 0.2) in the hybrid design. • 20 % higher cooling at same size while producing same product temperature. Indirect evaporative coolers (IEC) enable low-energy cooling of air without humidification. While a conventional IEC is limited to cooling incoming air down to its wet-bulb temperature, a regenerative IEC (M−cycle) can cool air further, approaching its dew point. In this study, a hybrid IEC-M−cycle design is proposed and evaluated for enhanced cooling, with initial cooling in the IEC portion, followed by subsequent cooling in the M−cycle section. Such a hybrid design produces the same product air temperature as a stand-alone M−cycle with 12–18 % lower heat transfer area. At a fixed system size, around 20 % higher cooling rate is achieved with the hybrid system while achieving the same product air temperature by optimizing the area fraction of the IEC section, and the recirculation flow rate. Overall, the proposed hybrid design enables improved indirect evaporative cooling at lower system sizes. [ABSTRACT FROM AUTHOR]

Abstract: The work was aimed at developing calcium-pectinate matrix tablet for colon-targeted delivery of meloxicam (MLX) microsponges. Modified quassi-emulsion solvent diffusion method was used to formulate microsponges (MS), based on 32 full factorial design. The effects of volume of dichloromethane and EudragitRS100 content (independent variables) were determined on the particle size, entrapment efficiency and %cumulative drug release of MS1–MS9. The optimized formulation, MS5 (d mean =44.47μm, %EE=98.73, %CDR=97.32 and followed zero order release) was developed into colon-targeted matrix tablet using calcium pectinate as the matrix. The optimized colon-targeted tablet (MS5T2) shielded MLX loaded microsponges in gastrointestinal region and selectively delivered them to colon, as vizualized by vivo fluoroscopy in rabbits. The pharmacokinetic evaluation of MS5T2 in rabbits, revealed appearance of drug appeared in plasma after a lag time of 7h; a t max of 30h with Fr=61.047%, thus presenting a formulation suitable for targeted colonic delivery. CLSM studies provided an evidence for colonic luminal retentive ability of microsponges at the end of 8h upon oral administration of MS5T2. Thus calcium pectinate matrix tablet loaded with MLX microsponges was developed as a promising system for the colon-specific delivery that has potential for use as an adjuvant therapy for colorectal cancer. [Copyright &y& Elsevier]

[Display omitted] • Fe 3 O 4 has been sulphurized and phosphurized, producing FeS and FeP, respectively. • FeP exhibited superior electrocatalytic activity for urea oxidation and water splitting. • Theoretical studies indicated that the addition of phosphorus atoms enhanced both the electrical and catalytic properties of the catalyst. • This study found that phosphorylation and sulfurization boost metal oxide catalytic activity. The slow kinetics of electrochemical urea and water oxidation processes at electrode surfaces, which can be recognised as promising resources for pollution-free hydrogen energy production, motivate the scientific community to design and fabricate low-cost, high-efficiency electrocatalysts. Because the performance of electrocatalysts is dependent on their structural, morphological, and electronic properties, herein, the tuning of these properties of Fe 3 O 4 @Ni-Foam via phosphorylation and sulfurization, yielding iron phosphide (FeP@Ni-Foam) and iron sulphide (FeS@Ni-Foam), with nanoneedles (along with microstructures) and nanoflower-like morphologies, respectively, is investigated. Among all the prepared samples, FeP is found to be the most effective electrocatalyst for the oxygen evolution process (OER), the urea oxidation reaction (UOR), and seawater electrolysis. The overpotentials observed for OER, UOR, and seawater splitting are significantly reduced when using FeP as compared to other materials, with values of 207 mV, 133 mV, and 287.1 mV, respectively, at a current density of 10 mA/cm2. The enhanced catalytic activity of FeP over FeS and Fe 3 O 4 is attributed to morphological changes, improved electronic conductivity, and exceptional endurance. The theoretical studies reveal that FeP has a better density of states over the fermi level than FeS and Fe 3 O 4 , lowering the energy barriers for the OER and UOR processes and demonstrating significant catalytic activity towards these processes. This work demonstrates that phosphorylation and sulfurization treatments can alter morphologies and electrical characteristics, hence improving the catalytic activity of the materials. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) have been the subject of intensive structural tuning via methods like pyrolysis for superior performance in electrocatalytic oxygen and hydrogen evolution processes (OER and HER) and supercapacitors. Here, a Co-MOF based on 2-methylimidazole was synthesized using a precipitation approach, and its electrochemical characteristics were tuned via pyrolysis at different temperatures, including 600, 700, and 800 °C. Characterization findings corroborated the formation of Co–N–C moieties from Co-MOF, and XPS analyses indicated that 700 °C was the optimal temperature for achieving a high density of Co–N–C moieties. The optimized Co-MOF-700 sample displayed remarkable HER and OER performance in terms of lower overpotentials of 75 mV and 370 mV as well as small Tafel slopes of 118 mV/dec and 79 mV/dec, respectively. Furthermore, at a current density of 1 A/g, the Co-MOF-700 sample had a specific capacitance of 210 F/g. The enhanced electrochemical properties of Co-MOF-700C as compared to other samples can be attributed to the availability of a high density of Co–N–C sites for catalytic reaction and its porous architecture. This study will expand the knowledge of how compositional and morphological changes in MOFs affect their utility in energy conversion and storage applications. [Display omitted] • The electrochemistry of Co-MOF was tuned via pyrolysis at different temperatures. • The optimized Co-MOF-700 sample displayed remarkable HER and OER performance. • Theoretical calculations were carried out to reveal the mechanisms of HER and OER. [ABSTRACT FROM AUTHOR]

• Cobalt phosphorus nanosheets were prepared using microwave heating. • CoP exposed surface sites and accelerated charge and mass transfer. • CoP possesses 184 mV and 260 mV of overpotential at 10 mA/cm2 for HER and OER, respectively. • CoP displays a specific capacitance of 4.87 F/cm2. • A low-cost, scalable, and efficient method for catalyst preparation was developed. Due to their redox-rich chemistry and distinctive electrical properties, Co-based electrocatalysts for H 2 and O 2 evolution reactions (HER and OER) have garnered attention; however, in addition to their limited activity, the chemical processes used to prepare them are time-consuming, costly, and potentially hazardous. Herein, we report a facile, rapid, and repeatable approach to preparing CoS x and CoP materials by using a nanoflower-like Co(OH) 2 precursor, which was grown in the liquid phase over Ni-foam under microwave impact. Further, the sulfurization of Co(OH) 2 nano-flowers produced rod-like CoS x structures. Whereas, phosphorization of Co(OH) 2 resulted in mesoporous nanosheet-like CoP architecture, which substantially exposed surface sites and fastened the charge as well as mass transfer, benefitting its electrocatalytic activity, as CoP catalysts displayed a lower HER and OER overpotential of 184 mV and 260 mV to carry 10 mA/cm2 current density than CoS x sample (233 mV and 284 mV), respectively. Moreover, CoP material is possessed to have a high specific capacitance of 4.87 F/cm2. Our cost-effective and scalable synthesis strategy solves the issues related to fabricating inexpensive, efficient, and high-quality transition metal-based materials for energy applications. [ABSTRACT FROM AUTHOR]