Soft Actuator with Biomass Porous Electrode: A Strategy for Lowering Voltage and Enhancing Durability

Electroactive artificial muscles with deformability have attracted widespread interest in the field of soft robotics. However, the design of artificial muscles with low-driven voltage and operational durability remains challenging. Herein, novel biomass porous carbon (BPC) electrodes are proposed. The nanoporous BPC enables the electrode to provide exposed active surfaces for charge transfer and unimpeded channels for ion migration, thus decreasing the driving voltage, enhancing time durability, and maintaining the actuation performances simultaneously. The proposed actuator exhibits a high displacement of 13.6 mm (bending strain of 0.54%) under 0.5 V and long-term durability of 99.3% retention after 550,000 cycles (∼13 days) without breaks. Further, the actuators are integrated to perform soft touch on a smartphone and demonstrated as bioinspired robots, including a bionic butterfly and a crawling robot (moving speed = 0.08 BL s-1). This strategy provides new insight into the design and fabrication of high-performance electroactive soft actuators with great application potential.

Co3O4 Nanoparticle-Modified Porous Carbons with High Microwave Absorption Performances

Carbon materials derived from natural biomaterials have received increasing attention because of their low cost, accessibility, and renewability. In this work, porous carbon (DPC) material prepared from D-fructose was used to make a DPC/Co₃O₄ composite microwave absorbing material. Their electromagnetic wave absorption properties were thoroughly investigated. The results show that the composition of Co₃O₄ nanoparticles with DPC had enhanced microwave absorption (-60 dB to -63.7 dB), reduced the frequency of the maximum reflection loss (RL) (16.9 GHz to 9.2 GHz), and had high reflection loss over a wide range of coating thicknesses (2.78-4.84 mm, highest reflection loss <-30 dB). This work provided a way for further research on the development of biomass-derived carbon as a sustainable, lightweight, high-performance microwave absorber for practical applications.

Porous Fe2O3 Nanorods on Hierarchical Porous Biomass Carbon as Advanced Anode for High-Energy-Density Asymmetric Supercapacitors

In this study, a novel negative electrode material was prepared by aligning α-Fe₂O₃ nanorods on a hierarchical porous carbon (HPC) skeleton. The skeleton was derived from wheat flour by a facile hydrothermal route to enhance conductivity, improve surface properties, and achieve substantially good electrochemical performances. The α-Fe₂O₃/HPC electrode exhibits enhanced specific capacitance of 706 F g⁻¹, which is twice higher than that of α-Fe₂O₃. The advanced α-Fe₂O₃/HPC//PANI/HPC asymmetrical supercapacitor was built with an expanded voltage of 2.0 V in 1 M Li₂SO₄, possessing a specific capacitance of 212 F g⁻¹ at 1 A g⁻¹ and a maximum energy density of 117 Wh kg⁻¹ at 1.0 kW kg⁻¹, along with an excellent stability of 5.8% decay in capacitance after 5,000 cycles. This study affords a simple process to develop asymmetric supercapacitors, which exhibit high electrochemical performances and are applicable in next-generation energy storage devices, based on α-Fe₂O₃ hybrid materials.