Advances in Graphene‑Based Electrode for Triboelectric Nanogenerator

With the continuous development of wearable electronics,wireless sensor networks and other micro-electronic devices,there is an increasingly urgent need for miniature,flexible and efficient nanopower generation technology.Triboelectric nanogenerator(TENG)technology can convert small mechanical energy into electricity,which is expected to address this problem.As the core component of TENG,the choice of electrode materials significantly affects its performance.Traditional metal electrode materials often suffer from problems such as durability,which limits the further application of TENG.Graphene,as a novel electrode material,shows excellent prospects for application in TENG owing to its unique structure and excellent electrical properties.This review systematically summarizes the recent research progress and application prospects of TENGs based on graphene electrodes.Various precision processing methods of graphene electrodes are introduced,and the applications of graphene electrode-based TENGs in various scenarios as well as the enhancement of graphene electrodes for TENG performance are discussed.In addition,the future development of graphene electrode-based TENGs is also prospectively discussed,aiming to promote the continuous advancement of graphene electrode-based TENGs.

NiCoP 1D nanothorns grown on 3D hierarchically porous Ni films for high performance hydrogen evolution reaction

Highly efficient,cost-effective,and durable electrocatalysts for hydrogen evolution reaction(HER)in water splitting is crucial for ene rgy conversion and sto rage.Herein,we report NiCoP 1D nanothorn arrays grown on 3D porous Ni film current collectors(Ni/NiCoP)as the novel electrocatalytic electrodes.The 3D hierarchically porous nickel films containing large 7±2μm pores and small pores less than 1μm are obtained through using hydrogen bubbles dynamic template method.The NiCoP 1D nanothorns are about 70 nm in diameter and 4-8μm in length.The porous Ni/NiCoP electrocatalytic electrodes demonstrate much higher catalytic activity and remarkable stability for long-term HER.The excellent electrocatalytic performance might be attributed to the inherent nature of highly catalytic active NiCo bimetal phosphides and the unique architecture of 1D nanothorn active materials directly integrated on the 3D hierarchically porous metallic nickel conductive skeletons.The developed electrode has been fabricated to the integrated solar-driven seawater-splitting system.

Defects and solarization in YAG transparent ceramics

Transparent ceramics are emerging as future materials for lasers, scintillation, and illumination. In this paper, an interesting and surprising phenomenon in YAG transparent ceramics is reported. UV light leads to significant changes in the microstructure of open volume defects and nano clusters as well as in the optical properties. Lightinduced lattice relaxation is suggested as the mechanism behind this intriguing behavior. The complex F-type color center with broad absorption bands is caused by the aliovalent sintering additives(Ca^2+∕Mg^2+) and Fe ion impurities. Two individual peaks in the thermoluminescence spectra illustrate both shallow and deep level traps.From positron annihilation lifetime data, vacancy clusters and nanovoids are detected and characterized, although these free-volume defects could not be observed by high-resolution transmission electron microscopy. The solarization induced by UV irradiation is associated with a change in the structure and size of defect clusters due to lattice relaxation. Therefore, this work shows how UV irradiation leads not only to a change in the charge state of defects, but also to a permanent change in defect structure and size. It significantly affects the optical properties of YAG ceramics and their performance in lasers and other optical applications. These results are crucial for advancing transparent ceramics technology.