1 Key Laboratory of Polar Materials and Devices(MOE) and Department of Electronics, East China Normal University, Shanghai 200241, China; 2 State Key Laboratory of ASIC and System, School of Microelectronics, Fudan University, Shanghai 200433, China
Abstract GeSe has recently emerged as a photovoltaic absorber material due to its attractive optical and electrical properties as well as earth abundancy and low toxicity. However, the efficiency of GeSe thin-film solar cells (TFSCs) is still low compared to the Shockley-Queisser limit. Point defects are believed to play important roles in the electrical and optical properties of GeSe thin films. Here, we perform first-principles calculations to study the defect characteristics of GeSe. Our results demonstrate that no matter under the Ge-rich or Se-rich condition, the Fermi level is always located near the valence band edge, leading to the p-type conductivity of undoped samples. Under Se-rich condition, the Ge vacancy (VGe) has the lowest formation energy, with a (0/2-) charge-state transition level at 0.22 eV above the valence band edge. The high density (above 1017 cm-3) and shallow level of VGe imply that it is the p-type origin of GeSe. Under Se-rich growth condition, Sei has a low formation energy in the neutral state, but it does not introduce any defect level in the band gap, suggesting that it neither contributes to electrical conductivity nor induces non-radiative recombination. In addition, Gei introduces a deep charge-state transition level, making it a possible recombination center. Therefore, we propose that the Se-rich condition should be adopted to fabricate high-efficiency GeSe solar cells.
Fund: This work was supported by Shanghai Academic/Technology Research Leader (Grant No. 19XD1421300), the National Natural Science Foundation of China (Grant No. 12174060), Program for Professor of Special Appointment (Eastern Scholar TP2019019), the National Key Research and Development Program of China (Grant No. 2019YFE0118100), State Key Laboratory of ASIC & System (Grant No. 2021MS006) and Young Scientist Project of MOE Innovation Platform.
Saichao Yan(闫赛超), Jinchen Wei(魏金宸), Shanshan Wang(王珊珊), Menglin Huang(黄梦麟), Yu-Ning Wu(吴宇宁), and Shiyou Chen(陈时友) Defect physics of the quasi-two-dimensional photovoltaic semiconductor GeSe 2022 Chin. Phys. B 31 116103
[1] Guo Q, Mahaprasad K, William N S, Robert W B, Eric A S, Rakesh A and Hugh W H 2008 Nano Lett.8 2982 [2] Zhou Y, Wang L, Chen S, Qin S, Liu X, Chen J, Xue D, Luo M, Cao Y, Cheng Y, Sargent E H and Tang J 2015 Nat. Photonics9 409 [3] Jeon N J, Na H, Jung E H, Yang T Y, Lee Y G, Kim G, Shin H W, Lee J and Seo J 2018 Nat. Energy3 682 [4] Wang T, Guo Y Q and Li S 2017 Chin. Phys. B26 103101 [5] Yang J and Wei S H 2019 Chin. Phys. B28 086106 [6] Liu X, Hong C, Ding Y, Liu X, Yao J and Dai S 2019 Chin. Phys. B28 014703 [7] Lu M, Xu J and Huang J W 2016 Chin. Phys. B25 098402 [8] Hirai Y, Kurokawa Y and Yamada A 2014 Jpn. J. Appl. Phys.53 012301 [9] Green M A, Dunlop E D, Levi D H, Hohl E J, Yoshita M and Ho B A 2019 Prog. Photovolt.27 565 [10] Wang W, Winkler M T, Gunawan O, Gokmen T, Todorov T K, Zhu Y and Mitzi D B 2014 Adv. Energy Mater.4 1301465 [11] Sinsermsuksakul P, Sun L, Lee S W, Park H H, Kim S B, Yang C and Gordon R G 2014 Adv. Energy Mater.4 1400496 [12] Steinmann V, Jaramillo R, Hartman K, Chakraborty R, Brandt R E, Poindexter J R, Lee Y S, Sun L, Polizzotti A, Park H, Gordon H R G and Buonassisi T 2014 Adv. Mater.26 7488 [13] Park H H, Heasley R, Sun L, Steinmann V, Jaramillo R, Hartman K, Chakraborty R, Sinsermsuksakul P, Chua D, Buonassisi T and Gordon R G 2015 Prog. Photovolt.23 901 [14] Minnam V R, Lindwall G, Pejjai B, Gedi S, Kotte T R, Sugiyama M, Liu Z K and Park C 2018 Sol. Energy Mater. Sol. Cells176 251 [15] Yun H S, Park B W, Choi Y C, Im J, Shin T J and Seok S I 2019 Adv. Energy Mater.9 1901343 [16] Zhou Y, Leng M, Xia Z, Zhong J, Song H, Liu X, Yang B, Zhang J, Chen J, Zhou K, Han J Y and Cheng J 2014 Adv. Energy Mater.4 1301846 [17] Wang L, Li D B, Li K, Chen C, Deng H X, Gao L, Zhao Y, Jiang F, Li L, Huang F, He Y, Song H, Niu G and Tang J 2017 Nat. Energy2 409 [18] Wen X, Chen C, Lu S, Li K, Kondrotas R, Zhao Y, Chen W, Gao L, Wang C, Zhang J, Niu G and Tang J 2018 Nat. Commun.9 2179 [19] Li Z, Liang X, Li G, Liu H, Zhang H, Guo J, Chen J, Shen K, San X, Yu W, Schropp R E and Mai Y 2019 Nat. Commun.10 125 [20] Zimmermann E, Pfadler T, Kalb J, Dorman J A, Sommer D, Hahn G, Weickert J and Schmidt L 2015 Adv. Sci.2 1500059 [21] Kondrotas R, Chen C and Tang J 2018 Joule2 857 [22] Hames Y and Eren S 2004 Sol. Energy77 291 [23] Musselman K P, Marin A, Schmi L and Macmanus J L 2012 Adv. Funct. Mater.22 2202 [24] Freysoldt C, Grabowski B, Hickel T, Neugebauer J, Kresse G, Janotti A and Van C G 2014 Rev. Mod. Phys.86 253 [25] Huang M, Xu P, Han D, Tang J and Chen S 2019 ACS Appl. Mater. Interfaces11 15564 [26] Xue D J, Yang B, Yuan Z K, Wang G, Liu X, Zhou Y, Hu L, Pan D, Chen S and Tang J 2015 Adv. Energy Mater.5 1501203 [27] Kshirsagar A S and Khanna P K 2019 Mater. Chem. Front.3 437 [28] Dimitri R J, Vaughn D, Michael A and Raymond E S 2010 J. Am. Chem. Soc.132 15170 [29] Wiedeneie E A 1975 Z. Anorg. Allg. Chem411 182 [30] Xue D J, Liu S C, Dai C M, Chen S, He C, Zhao L, Hu J S and Wan L J 2017 J Am. Chem. Soc.139 958 [31] Liu S C, Yang Y, Li Z, Xue D J and Hu J S 2020 Mater. Chem. Front.4 775 [32] Vaughn D, Sun D, Levin S M, Biacchi A J, Mayer T S and Schaak R E 2012 Chem. Mater.24 3643 [33] Chen M, Zha R H, Yuan Z Y, Jing Q S, Huang Z Y, Yang X K, Yang S M, Zhao X H, Xu D L and Zou G D 2017 Chem. Eng. J.313 791 [34] Shi G and Kioupakis E 2015 Nano Lett.15 6926 [35] Mukherjee B, Cai Y, Tan H R, Feng Y P, Tok E S and Sow C H 2013 ACS Appl. Mater. Interfaces5 9594 [36] Liu S C, Dai C M, Min Y, Hou Y, Proppe A H, Zhou Y, Chen C, Chen S, Tang J, Xue D J, Sargent E H and Hu J S 2021 Nat. Commun.12 670 [37] Hou G J, Wang D L, Ali R, Zhou Y R, Zhu Z G and Su G 2018 Sol. Energy159 142 [38] Lv X, Wei W, Mu C, Huang B and Dai Y 2018 J. Mater. Chem. A6 5032 [39] Hossain J, Mondal B K and Mostaque S K 2021 Semicond. Sci. Technol.37 015008 [40] Zi W, Mu F, Lu X, Cao Y, Xie Y, Fang L, Cheng N, Zhao Z and Xiao Z 2020 Sol. Energy199 837 [41] Shi L, Li Y and Dai Y 2015 Chempluschem80 630 [42] Cheng K, Guo Y, Han N, Su Y, Zhang J and Zhao J 2017 J. Mater. Chem. C5 3788 [43] Kresse G and Hafner J 1993 Phys. Rev. B47 558 [44] Kresse J F 1996 Phys. Rev. B54 11169 [45] Kresse J F 1996 Comp. Mater. Sci.6 15 [46] Blochl P E 1994 Phys. Rev. B50 17953 [47] John K B, Perdew P and Matthias E 1996 Phys. Rev. Lett.77 3865 [48] Heyd J and Scuseria G E 2004 J. Chem. Phys.120 7274 [49] Krukau A V, Vydrov O A, Izmaylov A F and Scuseria G E 2006 J. Chem. Phys.125 224106 [50] Grimme S 2004 J. Comput. Chem.25 1463 [51] Ektarawong A and Alling B 2018 J. Phys: Condens. Matter.30 29LT01 [52] Phillips L J, Savory C N, Hutter O S, Yates P J, Shiel H, Mariotti S, Bowen L, Birkett M, Durose K, Scanlon D O and Major J D 2019 IEEE J. Photovolt.9 544 [53] Christopher N, Savory and Scanlon D O 2019 J. Mater. Chem. A7 10739 [54] Huang M L, Zheng Z N, Dai Z X, Guo X J, Wang S S, Jiang L L, Wei J C and Chen S 2022 arXiv: 2201.02079 [cond-mat.mtrl-sci] [55] Zhang S, Li M L, Jiang M, Xiao H, Scanlon D O and Zu X T 2021 J. Phys. B: At. Mol. Opt. Phys.54 035003 [56] Ma J, Wei S H, Gessert T A and Chin K K 2011 Phys. Rev. B83 245207 [57] Yang J H, Park J S, Kang J, Metzger W, Barnes T and Wei S H 2014 Phys. Rev. B90 245202 [58] Huang M, Wang S S, Wu Y N and Chen S 2021 Phys. Rev. Appl.15 024035 [59] Zang Z 2018 Appl. Phys. Lett.112 042106 [60] Birkett M, Linhart W M, Stoner J, Phillips L J, Durose K, Alaria J, Major J D, Kudrawiec R and Veal T D 2018 APL Mater.6 084901 [61] Chen B, Chen G, Wang W, Cai H, Yao L, Chen S and Huang Z 2018 Sol. Energy176 98 [62] Chen B, Ruan Y, Li J, Wang W, Liu X, Cai H, Yao L, Zhang J M, Chen S and Chen G 2019 Nanoscale11 3968 [63] Zi W, Mu F, Lu X, Cao Y, Xie Y, Fang L, Cheng N, Zhao Z and Xiao Z 2020 Sol. Energy199 837 [64] Yang W, Zhang X and Tilley S D 2021 Chem. Mater.33 3467 [65] Liu S C, Li Z, Wu J, Zhang X, Feng M, Xue D J and Hu J S 2021 Sci. Chin. Mater.64 2118 [66] Okazak A 1958 J. Phys. Soc. Jpn. 13 1151 [67] Dimitri D V and Romesh J P 2010 J. Am. Chem. Soc.132 15170 [68] Shi L, Li Y and Dai Y 2015 Chempluschem80 630 [69] Shaabani L, Aminorroaya S, Byrnes J, Akbar A N and Blake G R 2017 ACS Omega2 9192 [70] Ding G, Gao G and Yao K 2015 Sci. Rep.5 9567 [71] Gomes L C, Carvalho A and Castro N A 2015 Phys. Rev. B92 214103 [72] Khan A A, Khan I, Ahmad I and Ali Z 2016 Mater. Sci. in Semicond. Process.48 85 [73] Murgatroyd P A, Smiles M J, Savory C N, Shalvey T P, Swallow J E, Fleck N, Robertson, Jackel C M, Alaria J, Major J D, Scanlon D O and Veal T D 2020 Chem. Mater.32 3245 [74] Kim Y and Choi I H 2018 J Korean Phys. Soc.72 238 [75] Solanki G K, Deshpande M P, Agarwal M K, Patel P D and Vaidya S N 2003 J. Mater. Sci. Lett.22 985
Altmetric calculates a score based on the online attention an article receives. Each coloured thread in the circle represents a different type of online attention. The number in the centre is the Altmetric score. Social media and mainstream news media are the main sources that calculate the score. Reference managers such as Mendeley are also tracked but do not contribute to the score. Older articles often score higher because they have had more time to get noticed. To account for this, Altmetric has included the context data for other articles of a similar age.
