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Recent Submissions

Elucidating the electrocatalytic activities of Pr-doped PtTiP nanocomposites for hydrogen evolution and methanol oxidation reactions
(Wiley, 2026) Basumatary, Padmini; Choi, Ji Hyeok; Sk, Mukkadar; Venkateswarlu, Sada; Misra, Biswajit; Thapa, Ranjit; Choi, Sun Hee; Jagadeesh, Rajenahally V.; Zbořil, Radek; Konwar, Dimpul; Yoon, Young Soo
Developing bifunctional electrocatalysts that combine high catalytic activity with long-term stability remains a major challenge in electrochemical energy conversions. Efficient hydrogen production via water splitting and methanol oxidation in direct methanol fuel cells are pivotal to realizing sustainable energy systems. However, few catalysts exhibit outstanding performance in both reactions. In this regard, we develop a praseodymium-doped platinum-titanium phosphide catalyst on modified nitrogen-doped multiwalled carbon nanotubes (PrPtTiP/N-MWCNT). Under acidic conditions (0.3 m H2SO4), PrPtTiP/N-MWCNT exhibits ultralow overpotentials of 8.2 and 12.2 mV at 10 and 100 mA cm- 2, respectively, which are substantially lower than those of PtP/N-MWCNT and commercial Pt/C. The developed catalyst maintains high activity at elevated current densities of up to 150 mA cm- 2 with minimal performance degradation. For methanol oxidation, PrPtTiP/N-MWCNT delivers a mass activity of 5.83 A mg-1 Pt, i.e., 3.3- and 8.3-fold enhancements over PtP/N-MWCNT and Pt/C, respectively. Comprehensive electrochemical, structural, and computational analyses confirm the excellent durability of the catalyst over 10,000 potential cycles and during prolonged chronoamperometric operation. Collectively, these results position PrPtTiP/N-MWCNT as a robust and highly active bifunctional electrocatalyst for hydrogen evolution and methanol oxidation in acidic environments.
Synergistic light-thermal-mass engineering of metal-coordinated covalent organic framework membranes for water purification
(Wiley, 2026) Sheng, Kai; Xiao, Zijie; Meng, Jiakun; Tian, Miaomiao; Cao, Xueli; Hou, Jingwei; Sun, Shi-Peng; Zhang, Yatao; Zhu, Junyong; Van der Bruggen, Bart
Membrane-based photothermal evaporation and separation offer a sustainable solution for both clean water access and environmental remediation. Covalent organic framework (COF) membranes are highly attractive due to their ordered porosity and chemical tunability, yet efficient light-to-heat-to-mass conversion at the interface remains challenging. Here we present a synergistic light-thermal-mass engineering strategy to overcome this limitation by utilizing cation-coordinated COF membranes. Through interfacial polymerization, we synthesized a photothermal COF with abundant nitrogen and oxygen chelating sites, followed by coordination with various divalent cations. Experimental and simulation results reveal that atomic dispersion of Co centers within a COF layer facilitates steeper interfacial gradients under one-sun irradiation, driving intensified buoyant convection to enhance mass transport and evaporation. The representative cobalt-COF (Co-COF) membrane achieves an extraordinary 99.996% ion removal, which meets stringent WHO standards. Complementary frontier molecular orbital analysis indicates substantial shifts in the HOMO and LUMO energy levels, resulting in a pronounced near-infrared redshift of the optical absorption edge. This substantially increases the photon budget for highly efficient photothermal and photocatalytic processes, conferring a high removal efficiency of volatile organic contaminants. This work underscores how precise metal ion coordination within COF structures significantly boosts both photothermal and photocatalytic efficiencies for sustainable water treatment.
Time-domain geoelectrical modeling and experimental validation of Ground Potential Rise in multilayer soil structures during fault events
(Wiley, 2026) Mbasso, Wulfran Fendzi; Harrison, Ambe; Dagal, Idriss; Mahmoud, Mohamed Metwally; Tsobze, Kenfack Saatong; Jangir, Pradeep; Shaikh, Muhammad Suhail; Smerat, Aseel
Accurate characterization of subsurface electrical behavior during high-energy fault events is critical for both geotechnical safety assessment and the protection of power infrastructure. This study presents a geophysically driven, time-domain modeling framework for Ground Potential Rise (GPR) in multilayer and anisotropic soils, integrating electromagnetic field theory with physics-informed arc resistance modeling. The methodology employs apparent resistivity profiling and soil impedance mapping, enabling high-resolution simulation of current density and voltage gradients under realistic subsurface conditions. A coupled numerical-experimental approach is implemented: finite-element simulations incorporating layered earth resistivity are calibrated against controlled fault injection tests using scaled grounding grids in stratified soil. The model achieves an average deviation of less than 4.7% from measured GPR and step/touch voltages, demonstrating strong predictive reliability. Results reveal that conventional steady-state and homogeneous soil assumptions can underestimate hazardous step voltages by up to 63% and misrepresent the spatial extent of GPR zones by more than a factor of two. Comparative analyses show that optimized grounding grids reduce surface current densities by over 90% compared to isolated systems, significantly enhancing compliance with safety thresholds. Beyond its immediate application to substation and renewable energy grounding, the framework offers a transferable geoelectrical tool for infrastructure risk mapping, lightning hazard assessment, and geotechnical site evaluations in complex soil environments.
Enhanced PID controller tuning for nonlinear continuous stirred-tank heaters using a modified Newton-Raphson optimizer with random opposition and Lévy-flight learning
(Springer Nature, 2025) Rizk-Allah, Rizk M.; Ekinci, Serdar; Jabari, Mostafa; Izci, Davut; Bajaj, Mohit; Blažek, Vojtěch; Rubanenko, Olena
Accurate temperature regulation in continuous stirred-tank heater (CSTH) systems is vital in chemical and thermal process industries, where deviations can cause energy inefficiencies, product quality degradation, or even safety hazards. However, CSTH systems pose a formidable control challenge due to inherent nonlinearities, parameter uncertainties, and susceptibility to external disturbances. Conventional proportional-integral-derivative (PID) tuning methods often struggle to handle these complexities, resulting in sluggish responses or instability. This study introduces a modified Newton-Raphson-based optimization (mNRBO), for optimal PID tuning tailored to nonlinear CSTH environments. The mNRBO framework integrates two key innovations: random opposition learning, to enhance population diversity and prevent premature convergence, and L & eacute;vy-flight-based guided learning, to improve global exploration and escape local optima. These mechanisms are systematically embedded into the Newton-Raphson-based optimizer (NRBO) to achieve a robust exploration-exploitation balance. A CSTH dynamic model is formulated using mass and energy conservation principles, and a multi-objective cost function evaluates rise time, settling time, overshoot, and steady-state error under realistic process constraints. Simulation studies compare mNRBO with NRBO, hippopotamus optimization, golden eagle optimizer, and slime mould algorithm. Results show that mNRBO achieves the lowest cost function value 53.29, smooth convergence with standard deviation 0.90, and superior closed-loop performance with rise time 62.05 s, settling time 206.88 s, overshoot 1.41%, and steady-state error 0.006%. These findings confirm that mNRBO delivers high-precision, disturbance-resilient control and is a promising solution for industrial thermal processes requiring reliability, efficiency, and precision.
Design and development of a flexural spindle mechanism enabled in micro drilling machine tool within a PLM environment
(Frontiers Media S.A., 2026) Shinde, Sachin Manohar; Solanke, Sachin; Diwan, Mohit; Bhole, Kiran S.; Salunkhe, Sachin; Čep, Robert; Nasr, Emad Abouel
The advent of designing flexural systems was to provide accurate micro and nano displacement between the assembly members of the mechanism. Applications that used these mechanisms included linear compressors, optomechanical devices, Stirling engines, cryocoolers, microcheck valves, Flexure-based Electromagnetic Linear actuators, and so on. This paper focuses on the machine-tool fabrication of a novel flexural mechanism encased within the spindle head of the microdrilling head. The mechanism cushioned the micro drill and protected it from permanent damage when encountering undeclared resistance in the material matrix. Furthermore, this paper focuses solely on building a 3-axis drilling machine tool in a Product Lifecycle Management environment. The study follows a systematized approach for validating the machine tool design, starting with the hierarchical assembly of components using various kinematic chains. The next phase involves assigning the necessary motions to these components. The final stage utilizes a virtual controller and post-processor to simulate and control machine tool movements. Validation is then performed on the simulated workpiece to ensure design accuracy and functionality. The key findings of the studies indicate that the designed mechanism can move in and out and can also puncture micro-holes in metal. This is the mechanism's capability, which is the novelty.