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Manufacturing of metal‐decorated carbon electrodes as a critical component of enzyme‐free glucose sensors has become an advanced strategy for fast and accurate glucose monitoring. By selectively irradiating the pre‐prepared chloroplatinic acid/polyimide (H2PtCl6/PI) precursor with photothermal energy, a creatively synchronized laser processing protocol is developed for assembling integrated three‐electrode system with platinum nanoparticle decorated laser‐induced graphene (PtNP‐LIG). In addition to the swift manufacturing of designable structures, laser power and raw‐material dosage are systematically explored as two key parameters to understand the process‐regulated microstructure and electro‐catalytic performance. Notably, by discovering the tuning mechanism for optimizing laser power‐dependent specific surface area of graphene backbone from 81.61 to 197.53 m2 g−1 and for enhancing H2PtCl6 concentration dependent Pt content from 0.75% to 4.16%, the sensitivity of PtNP‐LIG sensors to glucose oxidation has dramatically improved from 203.14 to 959.07 µA mM−1 cm−2, following closely the adjustable discipline of electrochemically active surface area (ECSA) from 37.75 to 104.19 mm2. Along with rapid response time, low limit of detection, and broad linear range, the proposed protocol is highly beneficial for designing and manufacturing next‐generation wearable human‐health related devices. [ABSTRACT FROM AUTHOR]

Facile and scalable manufacturing of metal decorated carbon electrodes is highly expected for next-generation energy-storage devices. Inspired by unique processing characteristics of laser-induced graphene (LIG) as well as electrochemical advantages of Pb, a full-laser protocol is developed for assembling Pb doped LIG (Pb-LIG) electrodes through two separate laser-irradiation processes to selectively irradiate polyimide (PI) for forming graphene framework and to selectively melt-and-recrystallize Pb powders. Along with high-efficient production and customizable sizes and shapes, Pb dosage and laser power are systematically investigated as two critical parameters to understand the process-structure relationship. By simultaneously considering the two factors, an interesting two-regime effect has been discovered, which is guiding for achieving optimized Pb content of 77.77 wt% as long as laser fluence per Pb dosage is around 100 J mg−1. Owing to clear redox faraday reaction, the integrated Pb content is indeed fundamental for promoting capacitive performance, by realizing a six-fold enhancement of areal capacitance from 25 to 128 mF cm−2. Finally, multiple Pb-LIG supercapacitors are facilely combined either in series or in parallel to expand its performance for energy-storage applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Functional electrodes with unique ion storage and rapid ion migration properties through microstructure and chemical-doping modulation are always crucial for rapid charging devices such as micro-supercapacitors (MSCs). In this work, proton exchange membrane named phosphoric acid (PA) doped polybenzimidazole membrane (PA-PBI) is studied as a unique precursor for assembling laser induced graphene (LIG) based electrodes (PA-PBI-LIG) in MSCs, toward the enhancement of energy storage performance via simultaneous heteroatoms doping, microporous structure improving and proton-conducting substrate introducing. By tuning PA concentration, the microporous structures perform adjustable specific surface area from 20.2 to 384.46 m2 g−1, thereby enhancing changeable capacitance from 2.44 mF cm−2 to 149 mF cm−2, with highest specific energy density of 20.7 μWh cm−2. To understand the mechanism, PA and the initiated free radicals are proposed to motivate microporous formation and heteroatoms doping during laser fabrication via unique laser absorption properties of PA. Additionally, PA-PBI substrates work synergistically on ions migration with microporous graphene, potentially promoting energy storage efficiency especially in the acid-based electrolyte. Overall, the raised PA-PBI-LIG electrodes simultaneously promote microporous, heteroatomic and multilayered graphene with proton conducting substrate, which show great potentials in micro energy storage devices. [Display omitted] • Phosphoric acid involved PBI-LIG improve micro pores, heteroatoms & ions transfer. • Phosphoric acid tunes the LIG specific surface area from 384.46 to 20.2 m2 g−1. • The optimized capacitance and energy density reach 149 mF cm−2 and 20.7 μWh cm−2. [ABSTRACT FROM AUTHOR]