What is optoelectronics?
The area of electronics that focuses on the development of both light-emitting and light-detecting devices is known as optoelectronics. Any device that uses a current and voltage to produce an output of light is encompassed within the field of optoelectronics. Also, phototransistors, which detect the electromagnetic energy of a light signal, converting it into electric current or voltage are encompassed within the discipline of optoelectronics. These light-detecting devices have received much focus in recent years as their advancements have allowed for the establishment of light-detecting devices with applications in light sensing and communication.
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Using nanomaterials in photovoltaics
The recent advancement of our understanding of nanostructures has revolutionized the sector of optoelectronics. Much research has led to the success of creating novel materials with useful physical properties of great use in optoelectronics by synthesizing nanostructures. This has led to the enhanced performance of electronic devices, as well as the advent of new research areas.
Perovskite materials have proven to be very beneficial in the photovoltaic segment of optoelectronics. Photovoltaics refers to the process of generated power from sunlight. Solar panels incorporate a photovoltaic cell that converts sunlight to electrical energy. Currently, there is an intense focus on discovering how to make these cells more efficient at converting energy, helping boost the power capacity of solar power systems.
The perovskite structure has the same crystal structure as calcium titanium oxide (CaTiO3). It is considered a nanomaterial because of its construction from nanocrystals. Perovskites are an attractive group of materials for use in several applications due to their unique physical and biochemical properties. For example, they are highly sensitive, have unique long-term stability and anti-interference ability. Since 2009, perovskite has been used in solar cells and is currently considered to be the most important and heavily researched area of new generation photovoltaic technologies, because of its superpower conversion efficiency.
The development of the perovskite solar cell
Ten years ago, Tsutomu Miyasaka led a team that innovated the use of hybrid halide perovskites in photovoltaics. The researchers developed a new kind of solar cell that incorporated a perovskite structured compound as the active layer responsible for harvesting light energy. While at the time the cells were inefficient, delivering just 3.8% power conversion efficiency, the efficiencies of the two cell types they produced have now surpassed 25 and 28%, following continued work on improving their functioning. The research into this area continues, as scientists explore ways to improve perovskite solar cells.
The first major advancements in perovskite solar cell technology since its invention in 2009 came three years later. In 2012, solid-state perovskite photovoltaic devices were created by scientists in Switzerland and South Korea that were able to overcome the previous limitations of the poor stability of the material in liquid-based dye-sensitized solar cells. Also, in 2012, British researchers figured out that materials can be used to transport electronic charges to the solar cell electrodes, leading to cells with higher efficiencies. This revelation resulted in halide perovskites becoming the focus of study for photovoltaic materials.
Following this, research efforts continued to focus on the unique physics and chemistry of perovskite materials, leading to remarkable advancements in our understanding of factors such as the nature of charge traps, causes of hysteresis in the current-voltage curves, ion migration, and defects and grain boundaries, which all impact device efficiency. In gaining a thorough understanding of these factors, scientists were able to further improve the efficiency of the perovskite layer of solar cells.
Perovskite solar cells continue to improve in their efficiency
While cadmium telluride and copper indium gallium selenide are more established solar cell technologies, their efficiency has already been overtaken by perovskite solar cells, which are now only behind silicon photovoltaics, which sit just slightly ahead with a 26.6% efficiency. The future will potentially see perovskite solar cells eventually overtake silicon, as intense research continues to explore the nature of perovskite materials and how they can be exploited in photovoltaics for optoelectronics.