346
S. S. B. Gunasekera et al.
Keywords CE · Platinum · Conducting polymers · Dye-sensitized solar cells
17.1 Introduction
The demand for energy is increasing rapidly with the growth of population and
industrialization. According to International Energy Outlook 2016 by U.S. Energy
Information Administration, the world energy demand is expected to be increased
by 48% from 2012–2040 for a period of 28 years (DOE/EIA-0484 (2016)). The
world energy production mainly depends on primary energy sources including oil,
coal followed by natural gases. The statistics indicate that, oil contributes around
33% to the total energy demand being the world’s leading fuel. The global demand
for oil in 2014 was 92.4% which is projected to be increased up to 99.1% by 2020
(World Energy Resources 2016, World Energy Council). The second primary energy
source in terms of consumption is coal and the demand for coal to produce energy
has increased by 64% from 2000 to 2014 (World Energy Resources 2016, World
Energy Council). The third primary energy source; natural gasses contributes 24%
to the global energy demand (World Energy Resources 2016, World Energy Council). Although the demand for the primary energy sources shows a dramatic increase,
these petroleum based sources are depleting at an alarming rate. Moreover, combustion of such fuels has led to increase in harmful greenhouse gases emitted into
the atmosphere. These adverse effects have led the scientists to focus research on
harvesting energy from renewable energy sources such as wind, tide, geothermal and
solar energy (World-nuclear.org. (2019), Renewables 2014-Global Status report).
Among many renewable energy sources, the use of solar power has been exponentially increased over the past decades as it is the most abundant, constant and least
polluting energy source which can be harvested (Lee 2019). The amount of energy
falling on the surface of the earth from the sun is about 3 × 10
24 J year
−1 or 10
4
times the consumption of the world. Covering 0.1% of the total area of the earth by
using 10% efficient solar cells (SCs) would be adequate to meet up the global energy
demand (Grätzel 2005).
Silicon based SCs are the most popular SCs in the market which give efficiencies
up to 15–17% (Lee et al. 2014). Major problem with SCs are their high manufacturing
cost, because it requires highly pure silicon (99.9999% of purity) making the SC
expensive (Braga et al. 2008). Promising solution for this problem was given by
Grätzel (2003) with the breakthrough on dye-sensitized solar cell (DSC) with many
desirable properties such as higher flexibility for the choice of starting materials,
higher transparency and less environmental pollution in addition to being low-cost
(O’Regan and Grätzel 1991; Grätzel 2003).
S. S. B. Gunasekera et al.
Keywords CE · Platinum · Conducting polymers · Dye-sensitized solar cells
17.1 Introduction
The demand for energy is increasing rapidly with the growth of population and
industrialization. According to International Energy Outlook 2016 by U.S. Energy
Information Administration, the world energy demand is expected to be increased
by 48% from 2012–2040 for a period of 28 years (DOE/EIA-0484 (2016)). The
world energy production mainly depends on primary energy sources including oil,
coal followed by natural gases. The statistics indicate that, oil contributes around
33% to the total energy demand being the world’s leading fuel. The global demand
for oil in 2014 was 92.4% which is projected to be increased up to 99.1% by 2020
(World Energy Resources 2016, World Energy Council). The second primary energy
source in terms of consumption is coal and the demand for coal to produce energy
has increased by 64% from 2000 to 2014 (World Energy Resources 2016, World
Energy Council). The third primary energy source; natural gasses contributes 24%
to the global energy demand (World Energy Resources 2016, World Energy Council). Although the demand for the primary energy sources shows a dramatic increase,
these petroleum based sources are depleting at an alarming rate. Moreover, combustion of such fuels has led to increase in harmful greenhouse gases emitted into
the atmosphere. These adverse effects have led the scientists to focus research on
harvesting energy from renewable energy sources such as wind, tide, geothermal and
solar energy (World-nuclear.org. (2019), Renewables 2014-Global Status report).
Among many renewable energy sources, the use of solar power has been exponentially increased over the past decades as it is the most abundant, constant and least
polluting energy source which can be harvested (Lee 2019). The amount of energy
falling on the surface of the earth from the sun is about 3 × 10
24 J year
−1 or 10
4
times the consumption of the world. Covering 0.1% of the total area of the earth by
using 10% efficient solar cells (SCs) would be adequate to meet up the global energy
demand (Grätzel 2005).
Silicon based SCs are the most popular SCs in the market which give efficiencies
up to 15–17% (Lee et al. 2014). Major problem with SCs are their high manufacturing
cost, because it requires highly pure silicon (99.9999% of purity) making the SC
expensive (Braga et al. 2008). Promising solution for this problem was given by
Grätzel (2003) with the breakthrough on dye-sensitized solar cell (DSC) with many
desirable properties such as higher flexibility for the choice of starting materials,
higher transparency and less environmental pollution in addition to being low-cost
(O’Regan and Grätzel 1991; Grätzel 2003).