Mixed sulfur and iodide-based lead-free perovskite solar cells

4 hours ago - Fully halide perovskite structures can only host inorganic metal cations such as Pb2+, Sn2+, and Ge2+ in the 2+ valence state to satisfy...
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Mixed sulfur and iodide-based lead-free perovskite solar cells Riming Nie, Aarti Mehta, Byung-wook Park, Hyoung-Woo Kwon, Jino Im, and Sang Il Seok J. Am. Chem. Soc., Just Accepted Manuscript • DOI: 10.1021/jacs.7b11332 • Publication Date (Web): 04 Jan 2018 Downloaded from http://pubs.acs.org on January 4, 2018

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Journal of the American Chemical Society

Mixed sulfur and iodide-based lead-free perovskite solar cells Riming Nie,† Aarti Mehta,† Byung-wook Park,† Hyoung-Woo Kwon,† Jino Im*,‡ and Sang Il Seok*,† †

School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 689-798, Republic of Korea ‡

Division of Advanced Materials, Korea Research Institute of Chemical Technology, 141 Gajeong-Ro, Yuseong-Gu, Deajeon 305-600, Republic of Korea

Supporting Information Placeholder ABSTRACT: The use of divalent chalcogenides and monovalent halides as anions in a perovskite structure allows the introduction of 3+ and 4+ charged cations in the place of the 2+ metal cations. Herein we report for the first time on the fabrication of solar cells exploiting methylammonium antimony sulfur diiodide (MASbSI2) perovskite structures, as light harvesters. The MASbSI2 was prepared by annealing under mild temperature conditions, via a sequential reaction between antimony trisulfide (Sb2S3), which is deposited by the chemical bath deposition (CBD) method, antimony triiodide (SbI3), and methylammonium iodide (MAI) onto a mesoporous TiO2 electrode, and then annealed at 150 °C in an argon atmosphere. The solar cells fabricated using MASbSI2 exhibited power conversion efficiencies (PCE) of 3.08%, under the standard illumination conditions of 100 mW/cm2.

Since organic-inorganic lead halide perovskite solar cells (PSCs) were first reported in 2009,1 their power conversion efficiencies (PCEs) of PSCs have increased to 22.1% in the past seven years.2-7 Nevertheless, issues with these PSCs, such as the use of toxic Pb and poor stability in humidity, remained unresolved. Generally, halide perovskites of the general formula AMX3 (A and M=1+ and 2+ cations, respectively; X = Cl, Br, I) can only host inorganic metal cations such as Pb2+, Sn2+ and Ge2+, which are in the 2+ valance state, to satisfy charge neutrality. One simple approach to replace toxic Pb is to use Sn in the PSCs.8-11 However, Sn2+ cations in the PSCs can be easily oxidized to Sn4+, resulting in relatively low performance and reproducibility. It was known that toxicity of Sb and Bi is lower than that of Pb.12 Pure halide mixtures of organic and Pb-free Bi3+ and Sb3+ cations, which are stable against oxidation, have been crystallized in the non-perovskite A3B2X9 (A = methylammonium (MA), and formamidinium (FA); B = Sb, Bi; X = Cl, Br, I) phase, but showed very low performance.13-15 Although oxide perovskites such as BiFeO3, BiFe2CrO6, and BiMnO3 are very stable, their low PCE makes them unsuitable for solar cell applications.16-20 Thus, chalcogenide ABX3 perovskites such as BaZrS3, SrZrS3, CaTiS3, CaZrSe3, SrSnSe3 and SrSnS3 etc. were evaluated through quantitative photoluminescence measurements,21 the calculated band gaps and absorption properties,22 or the first-principles computations.23 Antimony or bismuth chalcogenides, such as Sb2S3, Sb2Se3, Bi2S3 and Bi2Se3 are considered to be promising photovoltaic

materials, due to advantages, such as suitable band gaps, high absorption efficiencies, air/moisture-stability, and environmentally-friendly features.24-30 Although the PCEs of antimony or bismuth chalcogenides based solar cells are significantly lower than organic-inorganic lead halide PSCs, they show relatively strong air/moisture-stability, which is a critical requirement for PSCs. The incorporation of chalcogenide ions, such as S2- and Se2-, into the halide anion sites in perovskite structures, would enable the introduction of Sb3+, and Bi3+ into the ABX3 perovskite, through the mixture of divalent and monovalent anions. Here, we prepared for the first time MASbSI2 perovskite-like materials through spin-coating and thermal annealing MAI solution on SbSI, which was prepared by multi-cycle spin-coating and thermal annealing process with SbI3 solution on the Sb2S3 deposited by chemical bath deposition (CBD). X-ray diffraction (XRD) and transmission electron microscopy (TEM) and UV-Vis absorption spectroscopy, and density functional theory (DFT) computer simulation calculations were used to identify the formation of MASbSI2. Solar cells with the cell configuration (fluorine-doped SnO2 (FTO)/TiO2 blocking layer (BL-TiO2)/mesoporous TiO2 (mp-TiO2)/MASbSI2/hole transporting material (HTM)/Au) were fabricated, and exhibited PCE as high as 3.08%. In the absence of previous reports on MASbSI2, the tolerance factor introduced by V. M. Gold-schmidt, for the formation of a stable perovskite crystal-phase, was calculated from MA, Sb, S, I ionic radii, using the formula (1): 31 =

(  ) √ (  )

(1)

Where rA and rB are the effective ionic radii of the MA+ and Sb3+, which are 180 pm 32, 33 and 76 pm 32, respectively. rX was set to the average value (180 pm) of the effective ionic radii of two Ianions (220 pm 34) and one S2- anion (100 pm 35). The calculated tolerance factor of MASbSI2 is 0.99, which was close to that (1.0) of an ideal cubic perovskite structure. This demonstrated the ability of MASbSI2 to form a basic perovskite structure. The process for depositing MASbSI2 perovskite layers with coexisting S and I ions is illustrated in Scheme 1. The BL-TiO2 and mp-TiO2 were deposited onto clean patterned FTO glasssubstrates, by spray pyrolysis or spin-coating. First, Sb2S3 was deposited onto the FTO/BL/mp-TiO2 substrates, by CBD at 10 o 24,25,36,37 C. Subsequently, SbI3 solution in N,Ndimethylformamide (DMF) (0.02-0.2 M) was spin-coated onto the Sb2S3 layer at 1000-2000 rpm for 60 s, and the samples were

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thermally annealed in Ar or N2 gas at 150°C for 2 min, to form the SbSI layer.38 The conversion from Sb2S3 to SbSI can be easily observed by the color change from dark-brown to dark-red. After complete reaction with Sb2S3, excess SbI3 was removed by ultrasonic washing in DMF solution. Next, spin-coating and thermal annealing with methylammonium iodide (MAI) solution were performed to deposit the perovskite layer MASbSI2, with chemical reaction (2);

The samples were then ultrasonically cleaned in 2-propanol (IPA) solution for 5 min, to remove the remaining unreacted MAI. For solar cells, additionally, poly(2,6-(4,4-bis-(2-ethylhexyl)-4 H ctckioebta[2,1b ;3,4-b ′ ]dithiophene)-alt-4,7(2,1,3benzothiadiazole)) (PCPDTBT, 10 mg/mL) as HTM, was also spin-coated onto the resulting MASbSI2. A metal electrode was formed by thermally depositing 100 nm of Au onto the HTM, poly(3.4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) was used as an interface modifier.

SbSI + MAI → MASbSI2 (2)

Scheme 1. The process for preparing the MASbSI2 perovskite layer. Figure 1a shows the optimized crystal structure of the MASbSI2 perovskite, with sulfur atoms distributed along the Z-axis in the octahedral unit. Sb-S bonds were separated into longer (~3.6Å) and shorter (~2.27Å) bonds, and the Sb-I bond length was ~ 3.16Å. The experimental XRD patterns agreed well with the simulated one (Figure 1b), implying the feasibility of MASbSI2 perovskite-like phase synthesis, and this similar phenomenon was also observed in other studies.39 Different ordering of sulfur atoms leads to slight shift in XRD peaks (Figure S1). However, molecular dynamics and structural relaxation calculations revealed that the MASbSI2 perovskite with Z-axis-ordered sulfur atoms is stable within random rotation of MA molecules near room temperature, and its thermodynamic stability is comparable to other configurations. (See computation results in supplementary information) The XRD pattern of pure MASbSI2 powder is similar to that of the MASbSI2 film prepared as scheme 1, which further confirm the product is MASbSI2 (Figure S2). The formation of well-crystalline MASbSI2 was also observed by the highresolution TEM (Figure 1c). As can be seen in Figure 1d, the band-gap of MASbSI2, obtained from the Tauc plot using UV-Vis absorption spectrum, was 2.03 eV, with an absorption edge of approximately 600 nm. The photoluminescence (PL) spectra of MASbSI2 was shown in the inset. The PL peak did not match the absorption edge very well, which might be due to the fluctuating alloy potential of indirect bandgap alloys, and this phenomenon is close to those observed in the previous literature.39,40 The lifetime of MASbSI2 was shown in Figure S3. The structure of the MASbSI2 perovskite-like material was also confirmed by X-ray photoelectron spectroscopy (XPS) and energy-dispersive X-ray (EDX) spectrometry (Figures S4 and S5). The UV-Vis absorption spectra and XRD patterns for the starting materials, eg., Sb2S3, SbI3, MAI were shown in Figures S6 and S7. These results are completely different from those of MASbSI2, indicating that the product is not simply a homogeneous mixture of Sb2S3, SbI3 and MAI. The energy level of MASbSI2 was measured by using ultraviolet photoelectron spectroscopy (UPS). The full figure of UPS spectra is shown in Figure S8. Figures 2a and 2b show the magnified plots of the secondary electron cutoff, and the highest occupied

molecular orbital (HOMO) regions of the HeI UPS spectra for MASbSI2. In the left panel, MASbSI2 shows a kinetic energy of the cut-off edge of 4.25 eV, corresponding to a Fermi level (EF) of 4.25 eV. In the right panel, the valence band maximum (VBM) of MASbSI2 is located at 1.62 eV, below the EF. Based on these results and the band gap acquired from the Tauc plot (Figure 1c), the energy level of MASbSI2 was obtained and compared with TiO2 as electron transporting layer and PCPDTBT as HTM (Figure 2c). The conduction band minimum (CBM) and VBM of MASbSI2 were 3.84 eV and 5.87 eV, respectively.

Figure 1. a) The MASbSI2 configuration simulated by DFT calculation is presented by the ball and stick model with orange ball for Sb, purple for I, yellow for S, grey for C, brown for N, and white for H, b) Comparison of simulated and experimental XRD patterns, c) High-resolution TEM of glass/TiO2/MASbSI2, d) Tauc plot of glass/TiO2/MASbSI2. Inset: the corresponding UVVis absorption spectrum and the PL spectrum.

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Journal of the American Chemical Society Solar cells, with the configuration FTO/BL/mpTiO2/MASbSI2/PCPDTBT/PEDOT:PSS/Au, were fabricated. Figure S9 shows the image of the MASbSI2 perovskite solar cell. Figure 3a shows the surface image of mpTiO2/MASbSI2/PCPDTBT observed by the field emission scanning electron microscopy (FESEM), which was similar to that of bare mp-TiO2, indicating the unique distribution of MASbSI2 in mp-TiO2, and the efficient infiltration of PCPDTBT into mpTiO2. In the cross-sectional FESEM image of the MASbSI2 solar cell shown in Figure 3b, five distinct layers including FTO, TiO2BL, mp-TiO2/MASbSI2, HTM, and Au can be clearly observed. The device structures were also confirmed by the TEM measurements (Figure S10). Furthermore, the line EDX data (Figure S11) and the EDX mapping data (Figure S12), acquired from the yellow solid line and the yellow dotted rectangle (which were chosen randomly), respectively, in Figure 3b, also confirmed the uniform distribution of MASbSI2 throughout the mp-TiO2. Figure 3c shows the J–V curves of the most efficient MASbSI2 based solar cells measured with a 50-ms scanning delay in both reverse- and forward-scan modes under standard air-mass 1.5 global (AM 1.5 G) illumination. No hysteresis is observed in the J-V curves of the two modes. The corresponding performance parameters were a short-circuit current (JSC) of 8.12 mA/cm2, open-circuit voltage (VOC) of 0.65 V, and fill factor (FF) of 58.5%, yielding a PCE of 3.08%. The J-V curve of solar cells without MASbSI2 was shown in Figure S13. The external quantum efficiency (EQE) spectrum of the devices between 300 and 600 nm is shown in Figure 3d, and is similar to the onset wavelength of absorption. EQE spectrum observed from 600 to 850 nm of these devices can be attributed to the panchromatic photon-harvesting by a low band gap PCPDTBT as an HTM material.37 A current density of 7.67 mA/cm2 was obtained by integrating the overlap of the EQE spectrum with the AM 1.5 G solar photon flux, which was in excellent agreement with the photocurrent density measured from the J-V curves. To confirm the reproducibility of this method, the experiment was repeated to obtain the efficiency statistics. Figure 3e is a histogram of PCE the PCE for MASbSI2 PSCs, showing normal distribution, and an average of 2%. Figure 2. a) Secondary electron cutoff region, and b) Highest occupied molecular orbital (HOMO) region of the HeI UPS spectra for MASbSI2. The inset in b) is the magnified HOMO region in initial UPS data, c) Relative energy band diagram for MASbSI2.

Figure 3. a) Surface FESEM images of MASbSI2 deposited on mp-TiO2, b) Cross-sectional FESEM images of the solar cell with the configuration of FTO/BL/mp-TiO2/MASbSI2/HTM/Au. The yellow rectangle and line were used for mapping and line EDX, respectively, c) J-V curves in forward- and reverse-scan modes and d) EQE spectrum of the best-performing MASbSI2 solar cell under standard illumination conditions (100 mW/cm2) of air mass

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1.5 global (AM 1.5 G), e) Histogram of device efficiencies based on the 60 devices fabricated independently. Unencapsulated cells were stored in ambient conditions, with 60% humidity. As show in Figure 4a and 4b, MASbSI2 PSCs retained over 90% of their normalized initial PCEs for up to 15 days, with corresponding stability in JSC, VOC and FF. Figure 4c shows the PCE and JSC as a function of the soaking time (1 h), with the solar cells illuminated under standard illumination conditions (100 mW/cm2) of AM 1.5 G including UV radiation, and a bias near the maximum power of the corresponding devices (0.49 V). After an initial increase, both PCE and JSC were stable. The PCE of approximately 2.30%, was somewhat higher than the average value, further confirming its reliability. Figure 4d shows the results of the thermal stability testing the MASbSI2 solar cells, conducted with unencapsulated cells at 85oC in air, under 40% average relative humidity in the dark. After a 30-day storage, the devices retained 91% of their initial PCEs.

Corresponding Author E-mail: [email protected]; [email protected]

Notes The authors declare no competing financial interests.

ACKNOWLEDGMENT This work was supported by Global Frontier R&D Program for Multiscale Energy System (NRF-2011-0031565, NRF2016M3A6A7945503), Climate Change Program (NRF2015M1A2A2056542), and Wearable Platform Materials Technology Center (WMC- No.2016R1A5A1009926) through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning (MSIP). This work was also financially supported by the KIST-UNIST partnership program (1.160097.01/2.160482.01) and LG Display under LGDUNIST Incubation Program.

REFERENCES

Figure 4. (a, b) Changes in normalized PCE, JSC, VOC, and FF of unencapsulated MASbSI2 solar cells in ambient atmosphere with 60% humidity, as a function of storage time, c) Stabilized JSC and PCE for the MASbSI2 solar cells, measured under a bias near the maximum power point voltage at 0.49 V, d) Normalized PCEs of the MASbSI2 solar cells measured at 85 oC, as a function of storage time. In summary, MASbSI2-based PSCs were for the first time fabricated. Sb2S3 film was deposited by the CBD method, and multicycle of spin-coating and thermal annealing were performed, with SbI3 solution on the Sb2S3 layer, to obtain SbSI. MAI solutions were spin-coated and thermally annealed on SbSI, to deposit MASbSI2. The best-performing MASbI2-based solar cell exhibited PCE as high as 3.08%. Unencapsulated cells, stored in the dark ambient conditions (humidity = ~60%, temperature = ~25°C) retained 90% of their initial efficiency. This study suggested that the use of chalcogenide and halide mixed perovskite materials can be an effective strategy for the fabrication of efficient, cheap, and stable solar cells.

ASSOCIATED CONTENT Supporting Information Experimental details, calculation results and additional supplementary figures. The Supporting Information is available free of charge on the ACS Publications website.

AUTHOR INFORMATION

(1) Kojima A.; Teshima K.; Shirai, Y.; Miyasaka T. J. Am. Chem. Soc. 2009, 131, 6050. (2) Heo J. H.; Im S. H.; Noh J. H.; Mandal T. N.; Lim C.-S.; Chang J. A.; Lee Y. H.; Kim H.-J.; Sarkar A.; Nazeeruddin M. K.; Grätzel M.; Seok S. I. Nat. Photonics 2013, 7, 486. (3) Jeon N. J.; Noh J. H.; Kim Y. C.; Yang W. S.; Ryu S.; Seok S. I. Nat. Mater. 2014, 13, 897. (4) Jeon N. J.; Noh J. H.; Yang W. S.; Kim Y. C.; Ryu, S.; Seo J.; Seok S. I. Nature 2015, 517, 476. (5) Yang W. S.; Noh J. H.; Jeon N. J.; Kim Y. C.; Ryu S.; Seo J.; Seok S. I. Science 2015, 348, 1234. (6) Bi D.; Tress W.; Dar M. I.; Gao P.; Luo J.; Renevier C.; Schenk K.; Abate A.; Giordano F.; Correa Baena J.-P.; Decoppet J.-D.; Zakeeruddin S. M.; Nazeeruddin M. K.; Grätzel M.; Hagfeldt A. Sci. Adv. 2016, 2, e1501170. (7) Yang W. S.; Park B.-W.; Jung E. H.; Jeon N. J.; Kim Y. C.; Lee, D. U.; Shin S. S.; Seo J.; Kim E. K.; Noh J. H.; Seok S. I. Science 2017, 356, 1376. (8) Hao F.; Stoumpos C. C.; Cao D. H.; Chang R. P. H.; Kanatzidis M. G. Nat. Photonics 2014, 8, 489. (9) Noel N. K.; Stranks S. D.; Abate A.; Wehrenfennig C.; Guarnera S.; Haghighirad A.; Sadhanala A.; Eperon G. E.; Pathak S. K.; Johnston M. B.; Petrozza A.; Herz L.; Snaith H. Energy Environ. Sci. 2014, 7, 3061. (10) Lee S. J.; Shin S. S.; Kim Y. C.; Kim D.; Ahn T. K.; Noh J. H.; Seo J.; Seok S. I. J. Am. Chem. Soc. 2016, 138, 3974. (11) Liao W.; Zhao D.; Yu Y.; Grice C. R.; Wang C.; Cimaroli A. J.; Schulz P.; Meng W.; Zhu K.; Xiong R.; Yan Y. Adv. Mater. 2016, 28, 9333. (12) Hebig, J.-C.; Kühn, I.; Flohre, J.; Kirchartz, T. ACS Energy Lett. 2016, 1, 309. (13) Park B.-W.; Philippe, B.; Zhang X.; Rensmo H.; Boschloo G.; Johansson E. M. J. Adv. Mater. 2015, 27, 6806. (14) Hebig J.-C.; Kühn I.; Flohre J.; Kirchartz T. ACS Energy Lett. 2016, 1, 309. (15) Saparov B.; Hong F.; Sun J.-P.; Duan H.-S.; Meng W.; Cameron S.; Hill I. G.; Yan Y.; Mitzi D. B.; Chem. Mater. 2015, 27, 5622. (16) Yang S. Y.; Martin L. W.; Byrnes S. J.; Conry T. E.; Basu S. R.; Paran D.; Reichertz L.; Ihlefeld J.; Adamo C.; Mel-ville A.; Chu Y.-H.; Yang C.-H.; Musfeldt J. L.; Schlom D. G.; Ager III J. W.; Ramesh R. Appl. Phys. Lett. 2009, 95, 062909. (17) Choi, T.; Lee, S.; Choi Y. J.; Kiryukhin V.; Cheong, S.-W.; Science 2009, 324, 63. (18) Chakrabartty, J. P.; Nechache, R.; Harnagea, C.; Rosei, F.; Opt. Express 2014, 22, A80. (19) Grinberg, I.; West, D. V.; Torres, M.; Gou, G.; Stein, D. M.; Wu, L.; Chen, G.; Gallo, E. M.; Akbashev, A. R.; Davies, P. K.; Spanier, J. E.; Rappe, A. M.; Nature 2013, 503, 509. (20) Nechache, R.; Harnagea, C.; Li, S.; Cardenas, L.; Huang, W.; Chakrabartty, J.; Rosei, F.; Nat. Photon. 2015, 9, 61. (21) Niu, S.; Huyan, H.; Liu, Y.; Yeung, M.; Ye, K.; Blankemeier, L.; Orvis, T.; Sarkar, D.; Singh, D. J.; Kapadia, R.; Ravichandran, J. Adv. Mater. 2017, 29, 1604733.

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Journal of the American Chemical Society (22) Sun, Y.-Y.; Agiorgousis, M. L.; Zhang, P.; Zhang, S. Nano Lett. 2015, 15, 581. (23) Ju M.-G.; Dai J.; Ma L.; Zeng X. C. Adv. Ener. Mater. 2017, 7, 1700216. (24) Chang J. A.; Rhee J. H.; Im S. H.; Lee Y. H.; Kim H.-J.; Seok S. I. Nano Lett. 2010, 10, 2609. (25) Choi Y. C.; Lee D. U.; Noh J. H.; Kim E. K.; Seok S. I. Adv. Funct. Mater. 2014, 24, 3587. (26) Choi Y. C.; Mandal T. N.; Yang W. S.; Lee Y. H.; Im S. H.; Noh J. H.; Seok S. I. Angew. Chem. Int. Ed. 2014, 53, 1329. (27) Rath A. K.; Bernechea M.; Martinez L.; Garcia de Arquer F. P.; Osmond J.; Konstantatos G. Nat. Photonics 2012, 6, 529. (28) Rath A. K.; Bernechea M.; Martinez L.; Konstantatos G. Adv. Mater. 2011, 23, 3712. (29) Martinez L.; Bernechea M.; García de Arquer F. P.; Konstan-tatos G. Adv. Ener. Mater. 2011, 1, 1029. (30) Nair P. K.; Nair M. T. S.; García V. M.; Arenas O. L.; Peňa Y.; Castillo A.; Ayala I. T.; Gomezdaza O.; Sánchez A.; Campos J.; Hu H.; Suárez R.; Rincón M. E. Sol. Energ. Mat. Sol. C. 1998, 52, 313.

(31) V. M. Goldschmidt, Naturwissenschaften, 1926, 14, 477. (32) Shannon R. D. Acta Crystallogr., Sect. A: Found. Crystallogr. 1976, 32, 751. (33) Cohen B. N.; Labarca C.; Davidson N.; Lester H. A. J. Gen. Physiol. 1992, 100, 373. (34) Kieslich G.; Sun S.; Cheetham A. K. Chem Sci 2014, 5, 4712. (35) https://zhidao.baidu.com/question/1671912023086604147.html (36) Im S. H.; Lim C.-S.; Chang J. A.; Lee Y. H.; Maiti N.; Kim H.-J.; Nazeeruddin M. K.; Grätzel M.; Seok S. I. Nano Lett. 2011, 11, 4789. (37) Chang J. A.; Im S. H.; Lee Y. H.; Kim H.-j.; Lim C.-S.; Heo J. H.; Seok S. I. Nano Lett. 2012, 12, 1863. (38) Nie R. M.; Yun H.-s.; Paik M.-J.; Mehta A.; Park B.-w.; Choi Y. C.; Seok S. I. Adv. Ener. Mater. 2017, 1701901, DOI: 10.1002/aenm.201701901. (39) Adonin S. A.; Frolova L. A.; Sokolov M. N.; Shilov G. V.; Korchagin D. V.; Fedin V. P.; Aldoshin S. M.; Stevenson K. J.; Troshin P. A. Adv. Energ. Mater 2017, 1701140, DOI: 10.1002/aenm.201701140. (40) Tasviri M.; Sajadi-Hezave Z. Mol. Catal. 2017, 436, 174.

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