Photoactive layer

Last updated

A photoactive layer is used in solar cells for absorbing light. It can be found in all solar cells, but with different panels the photoactive layer is made of different materials. Inorganic layers are made from inorganic materials such as silicon. The film has a layer arrangement of electrodes and counter electrode with organic layers in between the two. The layer is found underneath the glass, adhesive, and reflection coating, but is the first required part of the cell. [1]

Contents

Definition

Photoactive means it can have a chemical reaction with sunlight and/or ultraviolet light. Most of the solar cell is photoactive, but the base of the solar cell only conducts electricity after it has been converted. It can also mean that it responds to photons photoelectrically. This can also relate to a physical reaction, but this does not occur within photoactive layers. [2]

Reported timeline of solar cell energy conversion efficiencies (from National Renewable Energy Laboratory (USA) PVeff(rev100921).jpg
Reported timeline of solar cell energy conversion efficiencies (from National Renewable Energy Laboratory (USA)

Efficiency

Layers that are thicker are sometimes preferred because they can absorb more light. While sometimes thinner ones are preferred for greater efficiency. [3] The light must pass through the band gap. For this to work the light must have a minimum energy depending on the cell to pass through. Different cells have a different minimum while the light below the minimum passes through the absorber. [4]

See also

Related Research Articles

<span class="mw-page-title-main">Electroluminescence</span> Optical and electrical phenomenon

Electroluminescence (EL) is an optical and electrical phenomenon, in which a material emits light in response to the passage of an electric current or to a strong electric field. This is distinct from black body light emission resulting from heat (incandescence), a chemical reaction (chemiluminescence), sound (sonoluminescence), or other mechanical action (mechanoluminescence).

<span class="mw-page-title-main">Photovoltaics</span> Method to produce electricity from solar radiation

Photovoltaics (PV) is the conversion of light into electricity using semiconducting materials that exhibit the photovoltaic effect, a phenomenon studied in physics, photochemistry, and electrochemistry. The photovoltaic effect is commercially used for electricity generation and as photosensors.

A "photoelectrochemical cell" is one of two distinct classes of device. The first produces electrical energy similarly to a dye-sensitized photovoltaic cell, which meets the standard definition of a photovoltaic cell. The second is a photoelectrolytic cell, that is, a device which uses light incident on a photosensitizer, semiconductor, or aqueous metal immersed in an electrolytic solution to directly cause a chemical reaction, for example to produce hydrogen via the electrolysis of water.

<span class="mw-page-title-main">Dye-sensitized solar cell</span> Type of thin-film solar cell

A dye-sensitized solar cell is a low-cost solar cell belonging to the group of thin film solar cells. It is based on a semiconductor formed between a photo-sensitized anode and an electrolyte, a photoelectrochemical system. The modern version of a dye solar cell, also known as the Grätzel cell, was originally co-invented in 1988 by Brian O'Regan and Michael Grätzel at UC Berkeley and this work was later developed by the aforementioned scientists at the École Polytechnique Fédérale de Lausanne (EPFL) until the publication of the first high efficiency DSSC in 1991. Michael Grätzel has been awarded the 2010 Millennium Technology Prize for this invention.

<span class="mw-page-title-main">Solar cell</span> Photodiode used to produce power from light on a large scale

A solar cell, or photovoltaic cell, is an electronic device that converts the energy of light directly into electricity by the photovoltaic effect, which is a physical and chemical phenomenon. It is a form of photoelectric cell, defined as a device whose electrical characteristics, such as current, voltage, or resistance, vary when exposed to light. Individual solar cell devices are often the electrical building blocks of photovoltaic modules, known colloquially as solar panels. The common single junction silicon solar cell can produce a maximum open-circuit voltage of approximately 0.5 volts to 0.6volts.

Hybrid solar cells combine advantages of both organic and inorganic semiconductors. Hybrid photovoltaics have organic materials that consist of conjugated polymers that absorb light as the donor and transport holes. Inorganic materials in hybrid cells are used as the acceptor and electron transporter in the structure. The hybrid photovoltaic devices have a potential for not only low-cost by roll-to-roll processing but also for scalable solar power conversion.

<span class="mw-page-title-main">Quantum dot solar cell</span> Type of solar cell based on quantum dot devices

A quantum dot solar cell (QDSC) is a solar cell design that uses quantum dots as the absorbing photovoltaic material. It attempts to replace bulk materials such as silicon, copper indium gallium selenide (CIGS) or cadmium telluride (CdTe). Quantum dots have bandgaps that are tunable across a wide range of energy levels by changing their size. In bulk materials, the bandgap is fixed by the choice of material(s). This property makes quantum dots attractive for multi-junction solar cells, where a variety of materials are used to improve efficiency by harvesting multiple portions of the solar spectrum.

An electrochromic device (ECD) controls optical properties such as optical transmission, absorption, reflectance and/or emittance in a continual but reversible manner on application of voltage (electrochromism). This property enables an ECD to be used for applications like smart glass, electrochromic mirrors, and electrochromic display devices.

<span class="mw-page-title-main">Multi-junction solar cell</span> Solar power cell with multiple band gaps from different materials

Multi-junction (MJ) solar cells are solar cells with multiple p–n junctions made of different semiconductor materials. Each material's p-n junction will produce electric current in response to different wavelengths of light. The use of multiple semiconducting materials allows the absorbance of a broader range of wavelengths, improving the cell's sunlight to electrical energy conversion efficiency.

Organic photovoltaic devices (OPVs) are fabricated from thin films of organic semiconductors, such as polymers and small-molecule compounds, and are typically on the order of 100 nm thick. Because polymer based OPVs can be made using a coating process such as spin coating or inkjet printing, they are an attractive option for inexpensively covering large areas as well as flexible plastic surfaces. A promising low cost alternative to conventional solar cells made of crystalline silicon, there is a large amount of research being dedicated throughout industry and academia towards developing OPVs and increasing their power conversion efficiency.

<span class="mw-page-title-main">Solar lamp</span> Lamp powered by one or more solar panels

A solar lamp, also known as a solar light or solar lantern, is a lighting system composed of an LED lamp, solar panels, battery, charge controller and there may also be an inverter. The lamp operates on electricity from batteries, charged through the use of solar panel

<span class="mw-page-title-main">Organic solar cell</span> Type of photovoltaic

An organic solar cell (OSC) or plastic solar cell is a type of photovoltaic that uses organic electronics, a branch of electronics that deals with conductive organic polymers or small organic molecules, for light absorption and charge transport to produce electricity from sunlight by the photovoltaic effect. Most organic photovoltaic cells are polymer solar cells.

<span class="mw-page-title-main">Optical rectenna</span>

An optical rectenna is a rectenna that works with visible or infrared light. A rectenna is a circuit containing an antenna and a diode, which turns electromagnetic waves into direct current electricity. While rectennas have long been used for radio waves or microwaves, an optical rectenna would operate the same way but with infrared or visible light, turning it into electricity.

<span class="mw-page-title-main">Copper indium gallium selenide solar cell</span>

A copper indium gallium selenide solar cell is a thin-film solar cell used to convert sunlight into electric power. It is manufactured by depositing a thin layer of copper indium gallium selenide solution on glass or plastic backing, along with electrodes on the front and back to collect current. Because the material has a high absorption coefficient and strongly absorbs sunlight, a much thinner film is required than of other semiconductor materials.

A plasmonic-enhanced solar cell, commonly referred to simply as plasmonic solar cell, is a type of solar cell that converts light into electricity with the assistance of plasmons, but where the photovoltaic effect occurs in another material.

<span class="mw-page-title-main">Solar cell research</span> Research in the field of photovoltaics

There are currently many research groups active in the field of photovoltaics in universities and research institutions around the world. This research can be categorized into three areas: making current technology solar cells cheaper and/or more efficient to effectively compete with other energy sources; developing new technologies based on new solar cell architectural designs; and developing new materials to serve as more efficient energy converters from light energy into electric current or light absorbers and charge carriers.

<span class="mw-page-title-main">Solar-cell efficiency</span> Ratio of energy extracted from sunlight in solar cells

Solar-cell efficiency refers to the portion of energy in the form of sunlight that can be converted via photovoltaics into electricity by the solar cell.

<span class="mw-page-title-main">Perovskite solar cell</span> Alternative to silicon-based photovoltaics

A perovskite solar cell (PSC) is a type of solar cell that includes a perovskite-structured compound, most commonly a hybrid organic–inorganic lead or tin halide-based material as the light-harvesting active layer. Perovskite materials, such as methylammonium lead halides and all-inorganic caesium lead halide, are cheap to produce and simple to manufacture.

<span class="mw-page-title-main">Thermogalvanic cell</span> Electrochemical cell in which a temperature difference produces a voltage

In electrochemistry, a thermogalvanic cell is a kind of galvanic cell in which heat is employed to provide electrical power directly. These cells are electrochemical cells in which the two electrodes are deliberately maintained at different temperatures. This temperature difference generates a potential difference between the electrodes. The electrodes can be of identical composition and the electrolyte solution homogeneous. This is usually the case in these cells. This is in contrast to galvanic cells in which electrodes and/or solutions of different composition provide the electromotive potential. As long as there is a difference in temperature between the electrodes a current will flow through the circuit. A thermogalvanic cell can be seen as analogous to a concentration cell but instead of running on differences in the concentration/pressure of the reactants they make use of differences in the "concentrations" of thermal energy. The principal application of thermogalvanic cells is the production of electricity from low-temperature heat sources. Their energetic efficiency is low, in the range of 0.1% to 1% for conversion of heat into electricity.

<span class="mw-page-title-main">Solaristor</span> Self-powered phototransistor

A solaristor is a compact two-terminal self-powered phototransistor. The two-in-one transistor plus solar cell achieves the high-low current modulation by a memresistive effect in the flow of photogenerated carriers. The term was coined by Dr Amador Perez-Tomas working in collaboration with other ICN2 researchers in 2018 when they demonstrated the concept in a ferroelectric-oxide/organic bulk heterojunction solar cell.

References

  1. "Photoactive Film, its Preparation and Use, and Preparation of Surface Relief and Optically Anisotropic Structures by Irradiating Said Film - Patent application".
  2. "The definition of photoactive".
  3. van Bavel, Svetlana (2009). "Relation between Photoactive Layer Thickness, 3D Morphology, and Device Performance in P3HT/PCBM Bulk-Heterojunction Solar Cells". Macromolecules. 42 (19): 7396–7403. Bibcode:2009MaMol..42.7396V. doi:10.1021/ma900817t.
  4. "Redirection Page | U.S. DOE Office of Science (SC)" (PDF). Archived from the original (PDF) on 2011-07-16. Retrieved 2011-07-26.