Publications by authors named "Kam Chew Leong"

We demonstrated the surface functionalization of a highly three-dimensional, superhydrophilic wicking substrate using light to immobilize functional biomolecules for sensor or microarray applications. We showed here that the three-dimensional substrate was compatible with photo-attachment and the performance of functionalization was greatly improved due to both increased surface capacity and reduced substrate reflectivity. In addition, photo-attachment circumvents the problems induced by wicking effect that was typically encountered on superhydrophilic three-dimensional substrates, thus reducing the difficulty of producing miniaturized sites on such substrate.

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Tin dioxide (SnO2) is a potential candidate to replace conventional titanium dioxide (TiO2) in dye-sensitized solar cells (DSSCs) because of its wider bandgap and higher electron mobility. However, SnO2 suffers from low band edge that causes severe backflow of electrons towards electrolyte (charge recombination). Herein, we demonstrate that gallium (Ga) doping can increase the band edge of SnO2, and we show that DSSCs using a Ga-doped SnO2 nano-cuboids based photoanode offer improved open circuit potential (~0.

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A highly sensitive miniature photonic crystal fiber refractive index sensor based on field mode excitation is presented. The sensor is fabricated by melting one end of a photonic crystal fiber into a rounded tip and splicing and collapsing the other end with a single-mode fiber. The rounded tip is able to induce cladding mode excitation, which resulted in an additional phase delay.

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