Chemical reaction kinetics-guided size and pore structure tuning strategy for fabricating hollow carbon spheres and their selective adsorption properties

Recent Progress of Hollow Carbon Nanocages: General Design Fundamentals and Diversified Electrochemical Applications

“…Based on these, the unique mesoporous structure and N,O codoping characteristic endue the car-bon nanocage electrode material a potential application in supercapacitors. In general, these hollow carbon nanospheres (microporous or mesoporous structures) constructed from silica hard template strategies [108][109][110][111][112][113][114][115] can exhibit different electrochemical capacitance properties, due to their different specific surface area and varying pore size or doping structures.…”

“…[ 112 ] More recently, by altering the reaction temperature from 6 to 45 °C or varying the time‐lag of adding RF carbon precursors from 0 to 180 min (based on the so‐called chemical reaction kinetics guided strategy), the sphere diameter, shell thickness, and pore size of the products can be successfully tailored in the range of 200–700, 10–100, and 4–19 nm, respectively. [ 113 ] These results indicate this SiO 2 @SiO 2 /RF surfactant‐free method is more powerful in tuning the pore sizes than the previous soft‐templating methods, [ 108–110 ] where the pores are controlled by the “soft” micelle size of surfactants (the pore size controllability is poor). However, the limitations of this double‐silica template self‐assembly strategy include that the pores are disordered and pore size distribution is relatively broad in mesoporous carbon nanocages.…”

“…[ 115 ] In general, the amorphous carbon nanocages prepared by spherical colloid templates (e.g., PS spheres and SiO 2 spheres) have very high dispersity and good uniformity. [ 108,111–114,36,37 ] The monodispersed graphene‐like carbon nanocages can also be prepared by using presynthesized metallic particle templates (e.g., Ni nanoparticles). [ 121–123 ] For example, uniform Ni nanoparticles (Ni‐NPs) were synthesized by the reduction reaction of NiCl 2 · 6 H 2 O, N 2 H 4 ·H 2 O, and NaOH, and then the graphene‐like carbon layers were coated on the surface of Ni‐NPs (with triethylene glycol as carbon source) by a successive carburization (refluxing at 220 °C) and carbon‐segregation (annealing at 500 °C) process, and the well‐shaped hollow graphene balls were obtained after etching Ni with 3 m HCl solution (see Figure A–C for details).…”

“…[74] Generally, the vacancy and edge carbon defects can be introduced or increased by physical treatment (such as highenergy ion beams and 𝛾 rays irradiation treatment) and chemical treatment (such as chemical reaction and oxidation etching for tailoring covalent bonds). [119,120] Apparently, the previously de-scribed activation [103][104][105][106] or template [111][112][113][114] pore-making strategies can be used as efficient methods for the fabrication of carbon defects on the shell of hollow carbon nanocages.…”

“…[115] In general, the amorphous carbon nanocages prepared by spherical colloid templates (e.g., PS spheres and SiO 2 spheres) have very high dispersity and good uniformity. [108,[111][112][113][114]36,37] The monodispersed graphene-like carbon nanocages can also be prepared by using presynthesized metallic particle templates (e.g., Ni nanoparticles). [121][122][123] For Figure 7.…”