Fossil fuels shortage, climate change and the recent socio-political events affecting Europe and the whole World are only few of the reasons pushing scientists to explore new frontiers and get creative in the field of energy harvesting and saving. The constantly increasing world population is hungry for energy to power cars for personal transportation, airplanes to travel around the world, to charge electronic devices and make our houses, factories, and anything one can imagine fully automated. Photovoltaics market is dominated by Silicon-based solar cells, which exploit the indirect interband transition of this material to convert visible radiation into electrical energy. In the last few years, advancements in materials science, lead to fabrication of technologies based on organic polymers (OPV) or organic-inorganic perovskites, which still only account to a small fraction of the market, mainly due to environmental stability issues. The total energy emitted from the Sun and reaching the surface of Earth is huge and if harvested could account for 100 times the needs of humankind. At the ground level it reaches 1 𝑘𝑊𝑚2⁄. However, only part of it is actively exploited to produce electric power, while almost 45% of it is lost due to spectral losses of silicon-based solar cells or due to conversion efficiency issues. Even if Si is able to harvest the visible and part of the UV region of the solar spectrum it completely neglects the NIR. Efficient photovoltaics beyond the visible spectral range, self-standing or in tandem with already existing technologies, could be a major breakthrough for green energy technologies. Such devices, given their transparency to Visible light, could be easily integrated with Si-based solar cells and represent a solution to the problem of spectral losses without interfering with Si absorption. Among the proposed solutions, hot electron extraction-based photovoltaic devices fabricated with NIR-absorbing plasmonic nanocrystals might represent a low-cost alternative to target all those photons left out by conventional photovoltaics.
La carenza di combustibili fossili, il cambiamento climatico e le recenti vicende socio-politiche che hanno investito l'Europa ed il mondo intero sono solo alcune delle ragioni che spingono gli scienziati ad esplorare nuove frontiere e diventare creativi nell'ambito dell'approvvigionamento e risparmio dell'energia. La popolazione mondiale, in costante aumento, è sempre più affamata di energia necessaria per il funzionamento di autovetture per il trasporto personale, aeroplani per viaggiare intorno al mondo, per la ricarica dei dispositivi elettronici e per automatizzare all'estremo le nostre case, fabbriche e qualunque altra cosa immaginabile. Il mercato del fotovoltaico è dominato dalle celle solari a base di silicio, le quali sfruttano la transizione indiretta interbanda di questo materiale per convertire la radiazione visibile in energia elettrica. Negli ultimi anni, l’avanzamento della scienza dei materiali ha permesso la fabbricazione di tecnologie basate su polimeri organici o perovskiti. Tuttavia, al momento rappresentano solo una piccola frazione del mercato, anche a causa di problemi relativi alla stabilità ambientale. L’energia totale emessa dal Sole e che raggiunge la superficie terrestre, se raccolta, potrebbe essere sufficiente per soddisfare cento volte i bisogni dell’umanità. Al livello del suolo raggiunge 1 kW/m2. Tuttavia, solo parte di questa radiazione è attivamente utilizzata per la produzione di energia elettrica, mentre quasi il 45% viene perso a causa del responso spettrale del Silicio e di problemi nell’efficienza di conversione. Nonostante il Silicio sia in grado di assorbire la radiazione visibile e parte di quella UV, trascura completamente il NIR. Dispositivi fotovoltaici efficienti al di fuori dello spettro visibile, self-standing o in tandem con tecnologie già consolidate, potrebbero essere di forte impatto per il mondo dell’energia rinnovabile. Questi dispositivi, considerata la loro trasparenza nel visibile, potrebbero facilmente essere integrati celle solari basate sul silicio, rappresentando una soluzione al problema del suo responso spettrale, senza interferire con il suo assorbimento. Tra le soluzioni proposte, i dispositivi fotovoltaici basati sull’estrazione di elettroni caldi, fabbricati con nanocristalli plasmonici con assorbimento nel NIR, potrebbero rappresentare un’alternativa low-cost per utilizzare tutti quei fotoni trascurati dal fotovoltaico convenzionale.
Plasmonic heavily doped-semiconductor nanocrystals thin films for hot electron extraction-based photovoltaic devices
Fabio, Marangi
2023
Abstract
Fossil fuels shortage, climate change and the recent socio-political events affecting Europe and the whole World are only few of the reasons pushing scientists to explore new frontiers and get creative in the field of energy harvesting and saving. The constantly increasing world population is hungry for energy to power cars for personal transportation, airplanes to travel around the world, to charge electronic devices and make our houses, factories, and anything one can imagine fully automated. Photovoltaics market is dominated by Silicon-based solar cells, which exploit the indirect interband transition of this material to convert visible radiation into electrical energy. In the last few years, advancements in materials science, lead to fabrication of technologies based on organic polymers (OPV) or organic-inorganic perovskites, which still only account to a small fraction of the market, mainly due to environmental stability issues. The total energy emitted from the Sun and reaching the surface of Earth is huge and if harvested could account for 100 times the needs of humankind. At the ground level it reaches 1 𝑘𝑊𝑚2⁄. However, only part of it is actively exploited to produce electric power, while almost 45% of it is lost due to spectral losses of silicon-based solar cells or due to conversion efficiency issues. Even if Si is able to harvest the visible and part of the UV region of the solar spectrum it completely neglects the NIR. Efficient photovoltaics beyond the visible spectral range, self-standing or in tandem with already existing technologies, could be a major breakthrough for green energy technologies. Such devices, given their transparency to Visible light, could be easily integrated with Si-based solar cells and represent a solution to the problem of spectral losses without interfering with Si absorption. Among the proposed solutions, hot electron extraction-based photovoltaic devices fabricated with NIR-absorbing plasmonic nanocrystals might represent a low-cost alternative to target all those photons left out by conventional photovoltaics.File | Dimensione | Formato | |
---|---|---|---|
Fabio Marangi_PLASMONIC HEAVILY DOPED-SEMICONDUCTOR NANOCRYSTALS THIN FILMS FOR HOT ELECTRONS EXTRACTION-BASED PHOTOVOLTAIC DEVICES.pdf
accesso solo da BNCF e BNCR
Dimensione
3.41 MB
Formato
Adobe PDF
|
3.41 MB | Adobe PDF |
I documenti in UNITESI sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
https://hdl.handle.net/20.500.14242/205281
URN:NBN:IT:POLIMI-205281