Abstract:
Organic photovoltaic has been developed for more than 30 years, however, within the last
decade the research field gained considerable in momentum. The amount of solar energy
lighting up Earth's land mass every year is nearly 3,000 times the total amount of annual
human energy use. But to compete with energy from fossil fuels, photovoltaic devices must
convert sunlight to electricity with a certain measure of efficiency. For polymer-based organic
photovoltaic cells, which are far less expensive to manufacture than silicon-based solar cells,
scientists have long believed that the key to high efficiencies rests in the purity of the
polymer/organic cell's two domains -- acceptor and donor.
The basic principle of organic solar cells is to place layer(s) of organic electronic material
between two metallic conductors of two different work functions. This difference of work
function sets up an electric field within the organic layer(s) which when absorbs light, causes
the excited electrons to be pushed towards positive electrode and holes towards negative
electrode. This thesis has been based on an optimized two layer organic solar cell which aims
to increase the photon absorption by increasing the interface area between donor and acceptor
levels.
This report summarizes the latest advances in the interfacial layers for bi-layer OSCs
(including bulk hetero-junction photovoltaic cells. Finally, a brief summary and some
perspectives about the current challenges and opportunities have been presented about this
interesting area of research.
Description:
We will begin our discussion of PV technology with a summary of the history of solar energy.
Already in the seventh century BC, people used split glasses in the light of the sun to
concentrate and so on. Later the ancient Greeks and Romans used mirrors for the same
purpose. In the eighteenth century, the Swiss physicist Horace-Benedict de Saussure created a
heating mesh, a kind of tiny greenhouse. When exposed to direct solar radiation, the
temperature in the innermost box can rise to a value of 108 ° C; These boxes could be
considered the world’s first solar collector to boil water and be warm enough to cook. In 1839, the French physicist Alexandre-Edmund Becquerel discovered the photovoltaic
effect when he was just 19 years old. He observed this effect in an electrolytic cell consisting
of two platinum electrodes placing an electronic signal.
In the 1860s and 1870s, French inventor Augustine Mouchot built the world's first solar-
powered steam engine using the Parabolic Trot solar collector. Mouchot was inspired by his
belief that coal resources were limited. At that time, coal was the source of energy for steam
engines. However, as coal became cheaper, the French government decided that solar energy
was too expensive and stopped funding Mouche's research.
In 1918, the Polish chemist Jan Kojokralaski discovered a method for enhancing the content
of high-quality crystals. The development of C-C technology began in the second half of the
20th century.
In 1953, the American chemist Dan Trivich first made a theoretical calculation of the
performance of solar cells for materials with different band gaps. The actual evolution of solar
cells, as we know it today, began at Bell Laboratories in the United States.
In 1999, worldwide installed photovoltaic power exceeded 1 GWP. By renewing the public
interest in solar energy since about 2000, environmental issues and economic issues have
become more important in public discussion. Since 2000, the POV market has therefore
transformed from a regional market to a global market, as discussed in Chapter 2, Germany
has pursued a progressive feed-in tariff policy, leading to a larger national solar market and
industry [19]. For 200 years, the Chinese government has been investing heavily in its PV
industry. As a result, China has been an influential PV module manufacturer for several years.
In 2012, global solar power surpassed the magic barrier of 100 gig watts [1 17]. Between
1999 and 2012, installed PV capacity increased by 100 factors. In other words, over the past
13 years, the average annual increase in installed PV capacity was about 40%.