Advances in wearable textile-based micro energy storage devices: structuring, application and perspective

Carbon Micro/Nano Machining toward Miniaturized Device: Structural Engineering, Large-Scale Fabrication, and Performance Optimization

With the rapid development of micro/nano machining, there is an elevated demand for high-performance microdevices with high reliability and low cost. Due to their outstanding electrochemical, optical, electrical, and mechanical performance, carbon materials are extensively utilized in constructing microdevices for energy storage, sensing, and optoelectronics. Carbon micro/nano machining is fundamental in carbon-based intelligent microelectronics, multifunctional integrated microsystems, high-reliability portable/wearable consumer electronics, and portable medical diagnostic systems. Despite numerous reviews on carbon materials, a comprehensive overview is lacking that systematically encapsulates the development of high-performance microdevices based on carbon micro/nano structures, from structural design to manufacturing strategies and specific applications. This review focuses on the latest progress in carbon micro/nano machining toward miniaturized device, including structural engineering, large-scale fabrication, and performance optimization. Especially, the review targets an in-depth evaluation of carbon-based micro energy storage devices, microsensors, microactuators, miniaturized photoresponsive and electromagnetic interference shielding devices. Moreover, it highlights the challenges and opportunities in the large-scale manufacturing of carbon-based microdevices, aiming to spark further exciting research directions and application prospectives.

Excellent performance supercapacitors with the compounding of Ni(OH)2 and ZIF-67 derived Co-C-N nanosheets as flexible electrode materials

Owing to the advantages of high theoretical capacity, low cost, and excellent chemical stability, Ni(OH)₂ is considered as a potential candidate for electrode materials of supercapacitors. However, its further applications are limited by its adverse surface chemical properties. In this paper, a composite material consisting of ZIF-67 derived Co-C-N nanosheets and Ni(OH)₂ was synthesized facilely on carbon cloth in situ, and based on the collective advantages of the various components, excellent electrochemical performance could be achieved when used as a flexible electrode material of supercapacitors. In detail, the as-obtained sample Ni(OH)₂/Co-C-N/CC exhibits an ultrahigh specific capacitance of 2100 F g^-1 at a current density of 1 A g^-1. Moreover, the further assembled asymmetric supercapacitor device exhibits a maximum energy density of 78.6 W h kg^-1 at a power density of 749.4 W kg^-1. Furthermore, the device also shows outstanding cycling stability with 90.2% capacitance retention after 5000 cycles of charge-discharge. Basically, the remarkable performance can be attributed to the well-developed structure, abundant active sites, complex beneficial components, and their intrinsic properties. Significantly, rational design can broaden the research directions of corresponding electrode materials.

A review of graphene derivative enhancers for perovskite solar cells

Due to the finite nature, health and environmental hazards currently associated with the use of fossil energy resources, there is a global drive to hasten the development and deployment of renewable energy technologies. One such area encompasses perovskite solar cells (PSCs) that have shown photoconversion efficiencies (PCE) comparable to silicon-based photovoltaics, but their commercialisation has been set back by short-term stability and toxicity issues, among others. A tremendous potential to overcome these drawbacks is presented by the emerging applications of graphene derivative-based materials in PSCs as substitutes or components, composites with other functional materials, and enhancers of charge transport, blocking action, exciton dissociation, substrate coverage, sensitisation and stabilisation. This review aims to illustrate how these highly capable carbon-based materials can advance PSCs by critically outlining and discussing their current applications and strategically identifying prospective research avenues. The reviewed works show that graphene derivatives have great potential in boosting the performance and stability of PSCs through morphological modifications and compositional engineering. This can drive the sustainability and commercial viability aspects of PSCs.

Optimization mechanism and applications of ultrafast laser machining towards highly designable 3D micro/nano structuring

The optimization mechanism of ultrafast laser machining is introduced. The specific applications of laser processed 3D micro/nano structures in optical, electrochemical and biomedical fields are elaborated, and perspectives are presented.

Compared EC-AFM Analysis of Laser-Induced Graphene and Graphite Electrodes in Sulfuric Acid Electrolyte

Flexible and economic sensor devices are the focus of increasing interest for their potential and wide applications in medicine, food analysis, pollution, water quality, etc. In these areas, the possibility of using stable, reproducible, and pocket devices can simplify the acquisition of data. Among recent prototypes, sensors based on laser-induced graphene (LIGE) on Kapton represent a feasible choice. In particular, LIGE devices are also exploited as electrodes for sensing in liquids. Despite a characterization with electrochemical (EC) methods in the literature, a closer comparison with traditional graphite electrodes is still missing. In this study, we combine atomic force microscopy with an EC cell (EC-AFM) to study, in situ, electrode oxidation reactions when LIGE or other graphite samples are used as anodes inside an acid electrolyte. This investigation shows the quality and performance of the LIGE electrode with respect to other samples. Finally, an ex situ Raman spectroscopy analysis allows a detailed chemical analysis of the employed electrodes.