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Hydrogen peroxide (H2O2) is a green oxidant widely used in water treatment and sustainable chemistry. Although many advanced materials exist for photo- and electrocatalytic production, H2O2 output and stability depend on reactor design and water quality. This study explores a scalable photochemical system employing bismuth vanadate-coated polymeric optical fibers (POF-BVO) illuminated by 440 nm LEDs. A single 20 cm, 3 mm diameter fiber generates H2O2 at 4.3 mg H2O2 h−1 (430 mg H2O2 gcat −1 h−1), with enhanced rates achieved using bundled fibers. The bundled configuration increases fiber packing density in the reactor to >120 m2 m−3, tripling that of flat-plate photocatalytic reactors. High H2O2 production is achieved using oxygen-permeable hollowfiber membranes to deliver pure O2 or air. The system performs consistently across pH 4−9 and in tap water, wastewater, or seawater. Phosphate ions improve H2O2 stability, resulting in higher concentrations. Over 21 days of continuous operation, the system produces >6 g L−1 of H2O2 with minimal performance degradation. Energy analysis reveals a 2−30x reduction in energy use compared to traditional slurry-based photocatalytic systems, with a three-fiber bundle reaching 27 kWh kg−1 comparable to electrochemical processes. These results demonstrate the potential of the POF-BVO platform as an energy-efficient and modular solution for decentralized H2O2 production. 

In this work, a 25 kW all silicon carbide (SiC) series-resonant converter (SRC) design is proposed to enable a single stage dc to dc conversion from 3kV to 540V (±270V) for future electric aircraft applications. The proposed SRC consists of a 3-level neutral-point-clamped (NPC) converter using 3.3kV discrete SiC MOSFETs on the primary side, a H-bridge converter using 900V SiC MOSFET modules on the secondary side and a high frequency (HF) transformer. The detailed design methods for the SRC power stage and the HF transformer are presented. Especially, a tradeoff between the complexity for the cooling system and the need for power density is addressed in the transformer design, leading to a novel multi-layer winding layout. To validate the effectiveness of the proposed SRC design, a converter prototype has been developed and comprehensive experimental studies are performed. 

The CLLC converter is widely used in the power electronic applications as a DC transformer, which can provide galvanic isolation, bidirectional power flow and an adjustable output voltage with the use of proper controls. As the most critical component in the CLLC converter, the high frequency (HF) transformer should be optimized according to the design targets, such as efficiency and power density. Starting with the analysis of the CLLC operating characteristics, this paper proposes a formal approach to design the HF transformer of a 100kW CLLC converter for a grid-tied application. The optimization method for the HF transformer is presented and the effect of the resonant inductor is analyzed. The optimized transformer is simulated with the finite element analysis (FEA) and Matlab/Simulink.