Defect-induced B4C electrodes for high energy density supercapacitor devices

Abstract

Boron carbide powders were synthesized by mechanically activated annealing process using anhydrous boron oxide (B2O3) and varying carbon (C) sources such as graphite and activated carbon: The precursors were mechanically activated for different times in a high energy ball mill and reacted in an induction furnace. According to the Raman analyses of the carbon sources, the I(D)/I(G) ratio increased from ~ 0.25 to ~ 0.99, as the carbon material changed from graphite to active carbon, indicating the highly defected and disordered structure of active carbon. Complementary advanced EPR analysis of defect centers in B4C revealed that the intrinsic defects play a major role in the electrochemical performance of the supercapacitor device once they have an electrode component made of bare B4C. Depending on the starting material and synthesis conditions the conductivity, energy, and power density, as well as capacity, can be controlled hence high-performance supercapacitor devices can be produced.

Boron Carbide as an Electrode Material: Tailoring Particle Morphology to Control Capacitive Behaviour

“…These results are in great agreement with the CV and PEIS results, further confirming that the morphology has a significant effect on the electrochemical performances of boron carbide electrodes. Different morphologies of boron carbide may contain different defect structures with different concentrations, which play a direct role in enhancing the electrochemical performance of the device by providing additional pathways for ion transport [ 34 , 56 ]. Defects can be controlled by alternating the morphology, which can be tailored by employing different synthesis routes.…”

“…Moreover, Chang et al demonstrated that core–shell structure B 4 C@C can also be employed as an electrode material for all-solid-state micro-supercapacitors [ 33 ]. In addition, the roles of intrinsic defects in the electrochemical performance of B 4 C electrodes have also been studied [ 34 ]. Moreover, boron carbide has excellent chemical stability and low-volume expansion [ 35 , 36 ].…”

Perspective on Micro-Supercapacitors

“…In addition, the transition metal silicides possess excellent interface properties with silicon and obtain low internal resistance because they are binder-free electrode materials (Ramly et al, 2018). It is worth noting that in addition to the above advantages, transition metal silicides also show intentional electrochemical properties, such as high theoretical energy FIGURE 5 | A brief timeline of the developments of promising of MSCs (In et al, 2008;Balcı et al, 2021;Yang et al, 2021a).…”

“… A brief timeline of the developments of promising of MSCs ( In et al, 2008 ; Balcı et al, 2021 ; Yang et al, 2021a ). …”

P-V-T equation of state of boron carbide

“…The low density and specific gravity make it ideal for use as lightweight armour and for space applications where protection from space debris impacts and resistance to radiation are both prerequisites in addition to maximizing the load–fuel ratio. Boron carbide is also used as a control material in thermal and fast reactors [ 3 ] and supercapacitor material [ 4 ]. Boron carbide is, however, shown to exhibit enigmatic behaviour under static and dynamic pressures that suggest the possibility of an elastic anomaly and loss of shear strength above 20 GPa.…”