Kwanciyar Hankali na Thermodynamic na Perovskites na Gishiri Guda Biyu Daga Rarraba Bangaranci

Teburin Abubuwan Ciki

1. Gabatarwa

Semiconductors na perovskite na gishirin karfe sun kawo sauyi ga na'urorin lantarki tare da halayensu na musamman da suka haɗa da manyan ma'auni na sha, ƙananan adadin tarko, da daidaitaccen bandgap. Perovskites na gishiri guda biyu MAPb(I_1-xBr_x)₃ suna ba da bandgap daga 1.6 eV (iodine tsantsa) zuwa 2.3 eV (bromide tsantsa), wanda ya sa su zama masu dacewa ga hasken rana na tandem da LED masu daidaitaccen launi. Duk da haka, waɗannan kayan suna fama da rarraba gishiri da haske ke haifarwa, inda yankuna masu wadatar iodine da bromide suke samuwa, suna haifar da cibiyoyin haɗawa waɗanda ke lalata aikin na'ura.

2. Hanyoyin Gwaji

2.1 Binciken Shaƙa na Lokaci-Dangane da Matsa Lamba

Mun yi amfani da binciken shaƙa na lokaci-lokaci (TAS) a ƙarƙashin matsin lamba daga yanayi zuwa 0.3 GPa. Ba kamar ma'aunin haske ba, TAS yana ba da damar bin diddigin yankuna masu wadatar iodine da bromide a lokacin rarrabuwa, yana ba da cikakken fahimta game da yanayin rabuwar bangaranci.

2.2 Matsi na Sinadari ta Musanyar Cation

An sami matsi na sinadari ta hanyar maye gurbin cations na methylammonium da ƙananan cations, yana rage girman crystal ba tare da matsin lamba na waje ba. Wannan hanyar tana kwaikwayon tasirin matsi na jiki yayin kiyaye ingancin kayan.

Yankin Matsa Lamba

0 - 0.3 GPa

Yankin Bandgap

1.6 - 2.3 eV

Ingantaccen Kwanciyar Hankali

Har zuwa x = 0.6

3. Sakamako da Bincike

3.1 Tasirin Matsa Lamba akan Rarraba Bangaranci

Matsa lamba na waje yana ƙara yawan kwanciyar hankali na ma'aunin gauru na gishiri. A matsa lamba na yanayi, rarrabuwa yana ƙarewa a x = 0.2, amma a ƙarƙashin matsi, wannan ƙimar ƙarshe tana matsawa zuwa kusan x = 0.6, yana faɗaɗa sararin abun da ke ciki mai amfani.

3.2 Matsi na Ƙarshe na Ma'aunin Gauru

Ƙimar x ta ƙarshe ta dogara ne akan matsa lamba na waje da kuma abun da ke ciki na farko. A ƙarƙashin matsa lamba, duka bangarorin masu wadatar iodine da bromide suna kusa da abun da ke ciki na farko, yana nuna ingantaccen kwanciyar hankali na thermodynamic a fadin faɗin gauru.

3.3 Fassarar Thermodynamic

An bayyana waɗannan tasirin ta hanyar gyara makamashin Gibbs ta hanyar PΔV: $\Delta G = \Delta H - T\Delta S + P\Delta V$. Matsi yana canza lokacin girma, yana matsar da mafi ƙarancin thermodynamic da kuma daidaita abubuwan da aka gauraya waɗanda in ba haka ba za su rabu.

4. Tsarin Fasaha

4.1 Tsarin Lissafi

Kwanciyar hankali na thermodynamic yana ƙarƙashin lissafin makamashin Gibbs: $G = U + PV - TS$, inda matsi ke shafar lokacin $P\Delta V$. Ga perovskites na gishiri guda biyu, makamashin gaurayawa na iya bayyana kamar: $\Delta G_{mix} = \Delta H_{mix} - T\Delta S_{mix} + P\Delta V_{mix}$.

4.2 Saitin Gwaji

Saitin TAS yana amfani da bugun laser na femtosecond tare da ƙwayoyin matsa lamba. An sami matsi na sinadari ta amfani da injiniyan cation tare da ƙananan ions kamar formamidinium ko cesium don rage ma'auni na lattice.

5. Hangen Nesa na Bincike

Gaskiya ta Asali

Wannan bincike yana kalubalantar al'adar gargajiya cewa rashin kwanciyar hankali na perovskite na gishiri guda biyu shine iyakar kayan da ba za a iya cin nasara ba. Nunin cewa kwanciyar hankali na thermodynamic ta hanyar PΔV na iya hana rarrabuwar bangaranci yana wakiltar sauyi a falsafar ƙirar perovskite.

Matsala ta Hankali

Ƙirar gwaji tana haɗa matsi na jiki (matsa lamba na waje) da matsi na sinadari (musanyar cation) da kyau, tana kafa ka'ida ta duniya: girman crystal da matsa lamba suna ƙayyadaddun kwanciyar hankali na gishiri. Wannan hanyar tana kama da dabarun da ake amfani da su a kimiyyar lissafi na matsa lamba da injiniyan kayan, kama da dabarun da ake amfani da su a binciken tantanin lu'u-lu'u a cibiyoyi kamar Cibiyar Kimiyya ta Carnegie.

Ƙarfi & Kurakurai

Ƙarfi: Tabbatar da hanyar biyu (matsi na jiki da na sinadari) yana ba da shaida mai ƙarfi. Amfani da TAS maimakon ma'aunin PL na al'ada yana ba da ƙuduri mafi girma na duka bangarorin rarrabuwa. Tsarin thermodynamic yana da fa'ida mai faɗi a cikin abubuwan da ke cikin perovskite.

Kurakurai: Yankunan matsa lamba da aka gwada (0.3 GPa) bazai wakilci yanayin na'ura mai amfani ba. Kwanciyar hankali na dogon lokaci a ƙarƙashin matsanancin aiki har yanzu ba a tabbatar ba. Binciken ya fi mayar da hankali kan MAPb(I_1-xBr_x)₃ ba tare da cikakken tabbaci akan sauran iyalai na perovskite ba.

Abubuwan Fahimta masu Aiki

Masu kera na'ura ya kamata su ba da fifiko ga injiniyan cation a cikin ci gaban perovskite na gishiri guda biyu, suna mai da hankali kan ƙananan cations waɗanda ke haifar da matsi na sinadari. Bincike ya kamata ya faɗaɗa don haɗa da injiniyan matsi a cikin fina-finai da binciken hanyoyin cation gauraye. Ya kamata a shigar da ka'idar kwanciyar hankali ta PΔV cikin binciken lissafi na abubuwan da ke cikin perovskite, kama da hanyoyin da ake amfani da su a cikin bayanan Ayyukan Kayan.

Wannan aikin ya yi daidai da sabbin abubuwan da ke faruwa a cikin kwanciyar hankali na perovskite, kwatankwacin hanyoyin a cikin ci gaban perovskite mara gubar da dabarun injiniyan mu'amala. Hangen nesa na thermodynamic yana ba da mafita mai mahimmanci fiye da hanyoyin jinkirin motsi, mai yuwuwa ba da damar kwanciyar hankali na shekaru 20 da ake buƙata don aikace-aikacen kasuwanci. Duk da haka, aiwatarwa mai amfani zai buƙaci fassara waɗannan fahimtar kayan guda zuwa gine-ginen na'urar fim mara laushi ba tare da lalata kaddarorin lantarki ba.

6. Aikace-aikace na Gaba

Kwanciyar hankali na perovskites na gishiri guda biyu yana buɗe aikace-aikace da yawa:

Tantanin Hasken Rana na Tandem: Perovskites masu kwanciyar hankali na bandgap mai faɗi don ingantattun na'urori masu haɗin gwiwa
LED masu Daidaitaccen Launi: Cikakken hasken gani tare da daidaitattun ma'auni na launi
Masu Gano Hoto: Amsar haske mai daidaitawa don aikace-aikacen firikwensin na musamman
Masu Gano X-ray: Ingantaccen kwanciyar hankali don na'urorin hoto na likita

Bincike na gaba ya kamata ya mayar da hankali kan haɓaka fina-finai masu injiniyan matsi, binciken madadin marasa gubar, da haɗa waɗannan perovskites masu kwanciyar hankali cikin gine-ginen na'urori na kasuwanci.

7. Nassoshi

Hutter, E. M. et al. Kwanciyar Hankali na Thermodynamic na Perovskites na Gishiri Guda Biyu Daga Rarraba Bangaranci. Rahoton Cell na Kimiyyar Jiki (2021)
Ayyukan Kayan. Bayanan Tsarin Crystal na Perovskite. https://materialsproject.org
Cibiyar Kimiyya ta Carnegie. Binciken Kimiyyar Lissafi na Matsa Lamba. https://carnegiescience.edu
Laboratorin Makamashi mai Sabuntawa na Ƙasa. Kwanciyar hankali na Tantanin Hasken Rana na Perovskite. https://nrel.gov/pv
Walsh, A. et al. Ƙirar Sabbin Perovskites don Tantanin Hasken Rana. Kayan Nature (2020)