Sensitized Solar Cells via Nanomaterials: A Recent Development in Quantum Dots-Based Solar Cells

The economic growth in many parts of the world during the past decade was sustainable because of affordable energy prices. The dependence on oil and electricity has made energy a vital component of our energy needs. In the 20th century, the population quadrupled, and our energy demand increased by 16 times. The exponential energy demand is exhausting our fossil fuel supply at an alarming rate. About 13 terawatts (TW) of energy is currently needed to sustain the lifestyle of 6.5 billion people worldwide. By the year 2050, we will need an additional 10 TW of clean energy to maintain the current lifestyle. To achieve this goal, alternative energy sources to coal,oil, and gas must be provided, such as power from wind and water, biomass, or solar energy. While a future energy mix will most likely be based on all of these sources, only the sun provides the earth with about 10
⁴
-times more energy than the global daily consumption. Solar energy can be converted to different kinds of energies, such as heat, hydrogen, and electricity. The most direct way is to convert sunlight into electricity by solar cells.