Chun Xiang Lin

Stabilization of silicon nanoparticles in graphene aerogel framework for lithium ion storage

The severe volume change and aggregation of silicon nanoparticles (SiNPs) when used as an anode for lithium ion batteries (LIBs) are the key issue. Here, we demonstrate a novel approach to wrapping SiNPs in three-dimensional reduced graphene oxide (RGO) aerogel. The RGO aerogel not only provides a porous network for entrapping SiNPs to accommodate the volume change during cycling, but also facilitates electrolyte transport. Furthermore, the continuous RGO network is favourable for electron transfer. The graphene-wrapped SiNPs were stable and displayed an excellent rate capacity, delivering a reversible capacity of about 2000 mA h g−1 after 40 cycles.

Bio-oil from cassava peel: A potential renewable energy source

In this work, liquid biofuel (bio-oil) was produced by pyrolizing cassava peel. The experiments were conducted isothermally in a fixed-bed tubular reactor at temperatures ranging from 400 to 600°C with a heating rate of 20°C/min. The chemical compositions of bio-oil were analyzed by a gas chromatography mass spectrometry (GC-MS) technique. For the optimization of liquid product, temperature was plotted to be the most decisive factor. The maximum yield of bio-oil ca. 51.2% was obtained at 525°C and the biofuel has a gross calorific value of 27.43 MJ/kg. The kinetic-based mechanistic model fitted well with experimental yield of pyrolysis products with the mean squared error (MSE) of 13.37 (R(2)=0.96) for solid (char), 16.24 (R(2)=0.95) for liquid (bio-oil), and 0.49 (R(2)=0.99) for gas.

Synthesis of magnetic hollow periodic mesoporous organosilica with enhanced cellulose tissue penetration behaviour

Commercially available barium ferrite BaFe12O19 (BaFeO) nanoparticles with a size of ∼100 nm have been successfully encapsulated inside the hollow periodic mesoporous organosilica (HPMO) host material, through a 2-step (coating and encapsulation) approach. The resultant magnetic HPMO (MHPMO) nanoparticles possess a relatively high saturated magnetization (25 emu g−1) and a high enzyme loading capacity (1.32 mg/mg). It is further demonstrated that MHPMO materials exhibited enhanced cellulose tissue penetration behaviour under applied external magnetic field, promising for delivery applications to plant cells.

Easy approach to synthesize N/P/K co-doped porous carbon microfibers from cane molasses as a high performance supercapacitor electrode material

In this study, we demonstrate a simple and low cost method to synthesize N/P/K co-doped porous carbon microfibers (CMFs) from a sugar-rich byproduct (cane molasses) as the precursor material. A two-step method for the synthesis of N/P/K co-doped porous CMFs involving electrospinning of precursor material followed by simple carbonization at various temperatures (773.15–1173.15 K) was successfully applied. The N/P/K co-doped porous CMFs exhibited high specific surface area (∼580 m2 g−1) and hierarchical porous structure. The potential application of N/P/K co-doped porous CMFs as supercapacitor electrodes was investigated in a two-electrode configuration employing aqueous K2SO4 solution and ionic liquids/acetonitrile (ILs/ACN) mixtures as the electrolytes. A series of electrochemical measurements include cyclic voltammetry, galvanostatic charge–discharge and cycling durability all confirmed that the CMF-1073.15 supercapacitor exhibited good electrochemical performance with a specific capacitance of 171.8 F g−1 at a current load of 1 A g−1 measured in 1.5 M tetraethylammonium tetrafluoroborate (TEABF4)/ACN electrolyte, which can be charged and discharged up to a cell potential of 3.0 V. The specific energy density and power density of 53.7 W h kg−1 and 0.84 kW kg−1 were achieved. Furthermore, the CMF-1073.15 supercapacitor showed excellent cycling performance with capacitance retention of nearly 91% after 2500 charge–discharge cycles, characterizing its electrochemical robustness and stable capacitive performance.