Lead-free tin perovskite solar cells

Perovskite solar cells (PSCs) have attracted great attention all over the world because of advantages adjustable band gap, long carrier diffusion length, high light-absorption coefficient, and solution processability organic metal halide perovskite absorbers. As first-generation PSCs, highest efficiency lead PSCs has reached 25.5%, which is comparable with that silicon cells. However, toxicity issue raises concern environmental pollution health problems; therefore, development lead-free materials desirable to produce next-generation PSCs. In past few years, tin emerged as a promising candidate for eco-friendly PV technology, their increased rapidly from approximately 6% more than 13%, realized by suppressing oxidation process Sn2+ Sn4+ slowing down fast crystallization rate pinhole-free highly oriented layer. Moreover, certified 11.22% at accredited test center recently been achieved using template-growth technique deposit absorber, will attract researchers participate in this field accelerate progress paper, comprehensive review on recent toward improving based equivalent circuit modeling provided. The improvement certain device parameter discussed separately, including short-circuit current density, open-circuit voltage, fill factor cell. Then, stability also briefly. Finally, perspectives future challenges how reach 20% efficiency, enlarging area, realizing scalable production are given detail. efficient stable crucial addressing toxic element lead. high-performance, photovoltaic technology power conversion (PCE) 11%, indicating potential applications. Here, we model We then discuss approaches viewpoint, such optimizing increasing light-harvesting surface passivation, regulating interface energy-level alignment. point out possibility reaching PCE issues regarding cell size future. expect these be helpful accelerating commercialization Development (PV) low cost an urgent need. emerging most third-generation metallic absorbers.1Jeon N.J. Noh J.H. Kim Y.C. Yang W.S. Ryu S. Seok S.I. Solvent engineering high-performance inorganic–organic hybrid cells.Nat. Mater. 2014; 13: 897-903Crossref PubMed Scopus (4934) Google Scholar, 2Wu Y. X. Chen W. Yue Cai M. Xie F. Bi E. Islam A. Han L. 18.21% area 1 cm2 fabricated heterojunction engineering.Nat. Energy. 2016; 1: 16148Crossref (487) 3Kim G.H. Lee T.K. Choi I.W. H.W. Jo Yoon Y.J. J.W. J. Huh D. et al.Methylammonium chloride induces intermediate phase stabilization cells.Joule. 2019; 3: 2179-2192Abstract Full Text PDF (700) 4Cai Ishida N. Li Noda T. Wu Naito H. 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Toward photovoltaics.Joule. 1231-1241Abstract (114) Pb arouses concerns problems, significantly limit large-scale commercialized applications.10Abate go free.Joule. 2017; 659-664Abstract (182) Therefore, desired So far, variety (Sn), bismuth (Bi), antimony (Sb), germanium (Ge), copper (Cu) studied. Among them, Sn similar outer electronic configuration (ns2 np2) ionic radius (149 pm Pb2+ 135 Sn2+),11Gu Lin R. Gao Tan Zhu Tin mixed lead–tin cells: application cells.Adv. 32e1907392Crossref (84) show ideal gap close Shockley-Queisser (1.3–1.4 eV) mobility, associated theoretical (more 30%).12Hao Stoumpos C.C. Cao D.H. Chang R.P.H. Kanatzidis Lead-free solid-state organic–inorganic 8: 489-494Crossref (1918) Since Snaith coworkers reported first 6.4%,13Noel N.K. Stranks S.D. Abate Wehrenfennig Guarnera Haghighirad A.A. Sadhanala Eperon G.E. Pathak S.K. Johnston M.B. al.Lead-free applications.Energy Environ. Sci. 7: 3061-3068Crossref remained negligible time owing reproducibility (Figure 1). Because two-dimensional (2D)-three-dimensional (3D) structure crystal orientation better against oxidation, greatly 9%,14Shao Liu Portale Fang H.H. Blake G.R. ten Brink Koster L.J.A. Loi M.A. Highly reproducible Sn-based 9% efficiency.Adv. Energy 1702019Crossref (507) research groups field. Meanwhile, architecture was changed normal (n-i-p) inverted (p-i-n) structures following reasons: (1) previous study length hole much shorter electron films, unfavorable extraction n-i-p PSCs;15Li P. Liang Su Xing Tao Song Low-dimensional Dion-Jacobson-phase photovoltaics improved stability.Angew. Int. Ed. Engl. 59: 6909-6914Crossref (67) (2) can accelerated chemical dopants transport used oxygen vacancies TiO2 surface, resulting poor stability.16Diau E.W.G. Jokar Rameez Strategies improve tin-based cells.ACS Lett. 1930-1937Crossref (96) contrast, growing number studies aimed minimizing voltage loss reducing defect density alignment perovskite/charge layer interface, further boosted 12% 13%.17Nishimura Kamarudin Hirotani Hamada Shen Iikubo Minemoto Yoshino Hayase tin-halide 13% efficiency.Nano 74: 104858Crossref (163) 18Wang Gu Jiang Bian Illumination durability high-efficiency under coordinated control phenylhydrazine halogen ions.Matter. 2021; 709-721Abstract 19Li Wei Ning perspective.Appl. Phys. 117060502Crossref (20) Recently, (Newport Laboratory, USA) templated-growth could fabricate high-quality large increase length.20Liu J.Y. Meng He Segawa Wang Templated growth FASnI3 crystals cells.Energy 2896-2902Crossref efficiencies it important summarize works development. Until now, many literature reviews focusing material design processing there viewpoint itself, provide guidelines directing performance. analysis model. First, classify our discussion work according three main parameters (JSC) light harvest ability; (VOC) matching devices; (FF) resistance. Although might interrelated, try analyze major influences specific simplify help researcher understand approach enhancement. Next, brief survey possible directions 20%, production, developing general, calculated measuring density-voltage (J–V) curves derive JSC, VOC, FF when irradiation intensity Pin:PCE=JSCVOCFFPin(Equation 1) Pin AM 1.5 G fixed, A powerful tool analyzing whole 2), includes constant source, diode, series resistance, shunt resistance: source indicates photocurrent (Jph) generated light, diode represents transfer cells, (3) Rs Rsh resistance respectively. mainly attributed functional layers, geometry, sheet transparent conductive oxide. affected pinholes shunting path, minority lifetime, non-radiative recombination rate. According model, output (J(V)) defined Jph reduced losses Rsh, so J–V characteristics described asJ(V)=Jph−J0[exp(q(V+JRs)nkT)−1]−V+JRsRsh,(Equation 2) where n ideality describing deviation condition, k Boltzmann constant, T temperature, q elemental charge, J0 reverse saturation diode. Based equation, section. At photo-generated carriers expected flow into external circuit, 2). When illumination incident photo flux Jphoton(λ), total flowing expressed follows:Jsc=q∫λminλmaxJphoton(λ)IPCE(λ)dλ,(Equation 3) λmax λmin represent maximum minimum wavelength absorbed photons, respectively, IPCE(λ) monochromatic photo-to-electron efficiency:IPCE(λ)=α(λ)ηc(λ)[1−R(λ)],(Equation 4) α(λ) ηc(λ) charge collection efficiency. R(λ) reflectivity cell, effectively anti-reflection substrate. Generally,α(λ) strongly photon only its energy larger absorbing materials. case positively related absorbance thickness, quality perovskite, defects vacancy. achieve should focus layer, well transportation processes Equation 3, JSC enhanced broadening spectral absorption edge (λmax), narrowing optical gap. VOC correlated This trade-off between leads 1.3–1.4 eV light-absorbing single-junction cell.21Nasti (ASnX 3 ) guide 10: 1902467Crossref (61) For typical ASnX3-type perovskites, monovalent cation [CH3NH3+ (MA+), CH(NH2)2+ (FA+), Cs+, etc.] X anion (I−, Br−), 1.23 (MASnI3) 2.4 (FASnBr3) tuning composition A-site cations or X-site anions. variation enables full coverage region producing Similar trend enlarged replacing bromide anions.22Ferrara Patrini Pisanu Quadrelli Milanese Tealdi Malavasi Wide band-gap through replacement: FA1−xMAxSnBr3 system.J. 5: 9391-9395Crossref Scholar,23Sabba Mulmudi H.K. Prabhakar R.R. Krishnamoorthy Baikie Boix P.P. Mhaisalkar Mathews anionic Br– substitution open free (CsSnI3-xBrx) 2015; 119: 1763-1767Crossref (246) impact quite different two kinds perovskites. MASnI3 CsSnI3 strong s–p antibonding orbital coupling I atoms provides broadest bandwidth and, thus, narrowest extends near-infrared (950–1,000 nm). results ability achieves PSCs.24Kumar M.H. Dharani Leong W.L. Shi Ding Ramesh Asta photocurrents vacancy modulation.Adv. 26: 7122-7127Crossref (709) 25Im Jin Freeman A.J. Antagonism spin–orbit steric effects causes anomalous evolution CH3NH3Sn1–xPbxI3.J. 6: 3503-3509Crossref (155) 26Marshall K.P. Walker Walton R.I. Hatton R.A. Enhanced hole-transport-layer-free photovoltaics.Nat. 16178Crossref (334) shows expanded orthorhombic lattice Sn–I bond decreased s-p overlap, 1.4 885 nm.27Koh T.M. Yantara Grimsdale A.C. S.G. Formamidinium E g applications.J. 14996-15000Crossref Despite slight decrease edge, effective solving JSC-VOC lower intrinsic other perovskites.28Shi H.S. Teng Yan Yip H.L. Effects physics perovskites.J. 15124-15129Crossref After fixing capability narrow beneficial photons compared spontaneous undesirable transition nonperovskite formula A2SnI6 presents (1.7–1.8 eV).26Marshall Scholar,29Liao Yu Grice C.R. Cimaroli Schulz Xiong R.-G. planar formamidinium triiodide achieving up 6.22%.Adv. 28: 9333-9340Crossref (443) These induce remarkable blue shift 3A). effort made mediate suppress (A) UV-vis spectra films. red line direction change ambient air. Reprinted permission al.26Marshall Copyright 2016 Springer Nature. (B) FASnI3, FASnI3-SnF2, FASnI3-SnF2-TMA Jen al.30Zhu Chueh Mao A.K.Y. Realizing via sequential deposition route.Adv. 30: 1703800Crossref (140) 2018 John Wiley Sons. (C) IPCE CDTA-treated devices. al.31Wu Efficient introducing π-conjugated Lewis base.Sci. China 63: 107-115Crossref (90) 2020 Science Press. acidity uncontrollable generate crystallinity weak absorption. key obtaining compact introduce extra interactions precursors additives, acid–base coordination hydrogen bonding interaction. Introducing interaction way slow Dimethyl sulfoxide (DMSO), base solvent, forming SnI2∙3DMSO adduct reaction SnI2 ammonium salts,32Hao Guo Marks T.J. Solvent-mediated CH3NH3SnI3 films depleted 137: 11445-11452Crossref (430) a(λ) derived dimethyl formamide. Similarly, al. trimethylamine (TMA) agent film.30Zhu formation SnI2-TMA complexes slowed (FAI) produced homogeneous 560–880 nm 3B). Consequently, 17 22 mA cm–2. stabilize base-SnI2 precisely.31Wu Our group introduced molecule, 2-cyano-3-[5-[4-(diphenylamino) phenyl]-2-thienyl]-propenoic acid (CDTA), perovskite. additive forms framework, leading coverage, 400–800 3C). same time, precursor another incorporation poly(vinyl alcohol) abundant hydroxyl (-OH) promotes O–H····I− species (SnI2 FAI).33Meng FASnI3-based bonding.Adv. 31e1903721Crossref (130) grains, yielding 12%. negative effect prevented antioxidant additives. Hydrazine derivatives applied during both fabrication operation hydrazine vapor atmosphere one-step ASnI3 reduce oxidized content redox path 2SnI62–+N2H4→2SnI42–+N2+4HI 4A).34Song T.B. Yokoyama Logsdon Wasielewski M.R. Aramaki Importance 139: 836-842Crossref (312) consequence, MASnI3-based 5 cm–2 19.9 treatment. directly destroy lattice. To overcome issue, hydrazinium (N2H5Cl) salt while preventing overreduction retain 4B).35Kayesh M.E. Chowdhury T.H. Matsuishi Kaneko Kazaoui J.J. coadditive.ACS 1584-1589Crossref (112) use N2H5Cl amount led enhancement 14.8 16.6 Possible mechanism al.34Song Precursor SEM images before after al.35Kayesh American Chemical Society. prepared solutions stirred powder 0, 1/3, 1, h, denoted Films (gray line), B (black C (red D (blue al.36Gu Rao Huang Improving purification.Sol. RRL. 1800136Crossref (D) Schematic illustration scavenging method. TM-DHP added precursor. Metallic nanoparticles