Waste Toner-Derived Carbon/Fe₃O₄ Nanocomposite for High-Performance Supercapacitor

Abstract

Electronic waste management is one of the key challenges for the green revolution without affecting the environment. The wide use of printer devices has brought a horde of discarded waste toner, which release ∼6000 tons of processed carbon powder into the atmosphere every year that would essentially pollute the atmosphere. Here, we propose a one-step thermal conversion of waste toner powder into carbon/Fe3O4 nanocomposites for energy storage applications. Recovered toner carbon (RTC) and toner carbon calcined at 300 °C (RTC-300) were characterized using various analytical tools. From the FE-SEM analysis, the presence of carbon particles with uniformly decorated Fe3O4 nanoparticles was confirmed. RTC-300 carbon was used as an electrode material for supercapacitors, and it exhibited a high specific capacitance of 536 F/g at a current density of 3 A/g, which is almost six times higher than that of the commercial mesoporous graphitized carbon black. RTC-300 showed excellent electrochemical stability of 97% over 5000 cycles at a high current density of 20 A/g. The fabricated symmetric cell using RTC-300 electrode materials in an aqueous electrolyte with a cell voltage of 1.8 V delivered a high energy and high-power density of 42 W h/kg and 14.5 kW/kg, respectively. The fabricated device is stable up to 20,000 cycles at a high current density of 20 A/g with a loss of 23% capacitance.

Quaternary Cu2FeSnS4/PVP/rGO Composite for Supercapacitor Applications

“…36 The capacitive and diffusive contributions in terms of the specific capacity in percentages of all the electrodes are shown in Figure 5 g. Figure 5 h displays the capacitive- and diffusion-controlled contributions calculated from CV scans at 5 mV/s for the best-performing Cu 2 FeSnS 4 /PVP/rGO electrode. 37 …”

Superior supercapacitive performance of Cu2MnSnS4 asymmetric devices

“…CA and OA respectively. The non-linear behavior of the graphs explored due to the ohmic drop of intrinsic resistance [49]. Specific capacity of AA, CA and OA with its EDLC (capacitive) and pseudocapacitive (diffusive) behavior is shown (Figure 7g).…”

Challenges and Emerging Trends in Toner Waste Recycling: A Review

“…By eliminating the microplastic components by heat treatment, waste toner generates carbon-coated ferric oxides for application as anodes in lithium-ion batteries [43]. Kaipannan et al reported an environmentally viable process for the thermal conversion of waste toner into carbon-coated iron oxides and applied them as active materials in supercapacitors [44]. The supercapacitors designed using the processed waste toner yielded better performance than those containing commercial mesoporous graphitized carbon black.…”