Modeling and Analysis of Wave Energy Harvester with Symmetrically Distributed Galfenol Cantilever Beams.

In response to the challenges of difficult energy supply and high costs in ocean wireless sensor networks, as well as the limited working cycle of chemical batteries, a cylindrical wave energy harvester with symmetrically distributed multi-cantilever beams was designed with Galfenol sheet as the core component. The dynamic equation of the device was established, and ANSYS transient dynamic simulations and Jiles-Atherton hysteresis model analysis were conducted to develop a mathematical model of the induced electromotive force of the Galfenol cantilever beam as a function of deformation. Experimental validation demonstrated that the simulated results of the cantilever beam deformation had an average error of less than 7% compared to the experimental results, while the average error between the theoretical and experimental values of the induced electromotive force of the device was around 15%, which preliminarily verifies the validity of the mathematical model of the device, and should be subject to further research and improvement.

In situ synthesized α-Fe2O3/BCN heterojunction for promoting photocatalytic CO2 reduction performance.

The conversion of CO2 into clean fuels by utilizing solar energy is still limited by a low photoconversion efficiency, and heterojunction photocatalysts are considered a very effective way to solve this problem. Herein, a heterojunction system consisting of hematite (α-Fe2O3) and boron carbonitride (BCN) was fabricated through a one-pot ionothermal method. α-Fe2O3 nanoparticles were grown in situ on the surface of BCN nanosheets, forming an α-Fe2O3/BCN heterojunction (FBCN) with tiny amounts of α-Fe2O3 (less than 2 wt%). The as-synthesized FBCN catalyst with 1.46 wt% α-Fe2O3 provides the highest CO2 photoreduction activity (55.1 µmol g-1 for CO) without any cocatalyst or sacrificial reagents, which is 3.9 times higher than that obtained for pure BCN. The enhanced CO2 reduction activity can be attributed to the high surface area and effective interface-contacted heterostructure, which endows the catalyst with broadband visible light absorption, suppressed separation of photogenerated electron holes, and promoted charge transfer. Meanwhile, cycling experiments demonstrate that the FBCN photocatalyst shows good reusability and stability. This work can assist in the design and preparation of BCN-based heterojunctions with effective CO2 reduction performance.