Native and Surface Modified Semiconductor Nanoclusters

Quantum Dot Solar Cells. Semiconductor Nanocrystals as Light Harvesters

“…The fastest electron transfer in the CdSe−TiO 2 system was observed with 2.4 nm-CdSe quantum dots. The rate constant of ∼1.2 × 10 s −1 in this experiment reflects an average lifetime of 83 ps. Other femtosecond transient studies have reported similar electron transfer rates between excited CdS/CdSe QDs and TiO 2 on a time scale of 2−50 ps. , Size-dependent electronic properties of semiconductor QDs are regarded as one of the most attractive features for attaining a band gap gradient in quantum dot solar cells.…”

“…Of particular interest are the size dependent properties such as size quantization effects in semiconductor nanoparticles and quantized charging effects in metal nanoparticles. [5][6][7][8][9][10][11] Recent efforts to synthesize nanostructures with well defined geometrical shapes (e.g., solid and hollow spheres, prisms, rods, tubes, and wires) and organize them as 2-and 3-dimensional assemblies have further expanded the possibility of developing new strategies for light energy conversion. [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] Quantum dot based solar cells have drawn a lot of attention during past few years because of the possibility of boosting the energy conversion efficiency beyond the traditional Shockley and Queisser limit of 32% for Si based solar cells.…”

“…Efforts are being made to design organic and inorganic hybrid structures that exhibit improved selectivity and efficiency toward light energy conversion. Of particular interest are the size dependent properties such as size quantization effects in semiconductor nanoparticles and quantized charging effects in metal nanoparticles. − Recent efforts to synthesize nanostructures with well defined geometrical shapes (e.g., solid and hollow spheres, prisms, rods, tubes, and wires) and organize them as 2- and 3-dimensional assemblies have further expanded the possibility of developing new strategies for light energy conversion. − …”

Chemistry and Properties of Nanocrystals of Different Shapes

“…For example, the electron injection happens around 200 fs, 50 fs, and <100 fs for the systems of coumarin 343, N 3 , , and anthocyanin dye-sensitized TiO 2 nanoparticles, respectively. The back electron transfer occurs much more slowly, usually from 10 ps to μs, and also depends on the nature of the dye and the nanoparticles. − …”

Meeting the Clean Energy Demand: Nanostructure Architectures for Solar Energy Conversion

“…Organic and inorganic hybrid structures that exhibit improved selectivity and efficiency toward catalytic processes have been designed. Size dependent properties such as size quantization effects in semiconductor nanoparticles and quantized charging effects in metal nanoparticles provide the basis for developing new and effective systems. − These nanostructures provide innovative strategies for designing next generation energy conversion devices. − Recent efforts to synthesize nanostructures with well-defined geometrical shapes (e.g., solid and hollow spheres, prisms, rods, and wires) and their assembly as 2- and 3-dimensional assemblies has further expanded the possibility of developing new strategies for light energy conversion. − …”