Controllable self‐propagating reduction of graphene oxide films for energy‐efficient fabrication

Abstract

The reduction of graphene oxide (GO) generally involves the use of chemical agents or high-temperature processes, raising concerns about safety, environment, and energy consumption issues. While self-propagating reduction of GO films was observed to produce functional rGO, potentially mitigating these issues, its process control has not yet been extensively explored. This study proposes a controllable self-propagating reduction of GO films by adjusting the base temperature of the films within low values (50 C-90 C). For understanding the reduction mechanism, the speed and peak temperature of the moving reduction front were measured in real-time, and a heat transfer model was proposed to explain the self-propagating reduction based on the observed reduction kinetics. When used for binder-free supercapacitor electrodes, the rGO films exhibited competitive specific capacitance (112 F/g) and excellent capacitance retention (94%) after 10 000 cycles. This study opens a new avenue for efficiently exploiting the self-propagating reduction of GO films to produce high-quality rGO at a minimal energy cost.

Thermal-needle-triggered cascade reduction of graphene oxide for controllable moving trajectory into conductive patterns

“…The sensitivity of this reaction may offer guidance for safe storage of GO with a high O/ C ratio, e.g., below 200 1C, or with the presence of water. Considering the inconsistent reports on self-reduction of GO, [29][30][31] the thermal reduction mechanism could also provide a clue for laser writing on GO substrates without the occurrence of cascade reduction for high precision, e.g., with a low O/C ratio of GO, low film thickness, and on cold/heat-conductive substrates. More importantly, this study offers a promising approach for graphene patterning by triggering with a thermal needle and controlling with pre-infiltration of hydrophilic materials.…”

“…4 Moreover, a cascade reduction reaction was reported only on hot substrates or hanging in air. 29,30 Fig. 4A shows that the reduced GO showed super-dispersibility in many organic solvents (e.g., DMF), without showing clear aggregation in B60 days.…”

“…4 Moreover, a cascade reduction reaction was reported only on hot substrates or hanging in air. 29,30…”

“…, below 200 °C, or with the presence of water. Considering the inconsistent reports on self-reduction of GO, 29–31 the thermal reduction mechanism could also provide a clue for laser writing on GO substrates without the occurrence of cascade reduction for high precision, e.g. , with a low O/C ratio of GO, low film thickness, and on cold/heat-conductive substrates.…”

Exploring Conducting Polymers as a Promising Alternative for Electrochromic Devices

“…Therefore, different strategies have been intensively investigated to save energy or use alternative fossil fuels such as coal, gas, and oil. Cutting-edge technologies that have been applied to date for this purpose include photocatalysts, [1][2][3][4][5][6] supercapacitors, [7,8] batteries, [9,10] carbon dioxide reduction, [11,12] hydrogen energy, [13][14][15][16][17][18] and electrochromic devices (ECDs). [19][20][21][22] Among them, ECDs are a state-of-the-art approach to saving energy because of their distinctive performance.…”