VOC Measurements Research Articles

Light oxygenated volatile organic compound concentrations in an Eastern Mediterranean urban atmosphere rivalling those in megacities

Highly resolved measurements of primary and secondary oxygenated volatile organic compounds (OVOCs) by proton-transfer-reaction mass spectrometry (PTR-MS) and the AMOVOC sampler (Airborne Measurements Of VOC) were performed in Beirut, Lebanon, during the ECOCEM (Emissions and Chemistry of Organic Carbon in the East Mediterranean) experiments. The OVOC concentrations (0.15–7.0 ppb) rival those reported for international megacities like Paris, Tokyo, or São Paulo (0.3–6.5 ppb). This study highlights the seasonal variability of OVOCs, the potential role of background pollution on OVOC concentrations, traffic emissions of OVOCs, and the secondary production of OVOCs during both summer and winter.The primary and secondary OVOC fractions were estimated using two methods based on the night-time emission ratio and photochemical age. Our calculations coupled with a correlation analysis revealed the following: firstly, background concentrations contributed significantly, especially for longer-lived OVOCs, such as methanol and acetone (30%–80%). Secondly, secondary production in summer increased up to 60%, except for methanol and isoprene oxidation products, i.e., for methacrolein and methyl vinyl ketone. Thirdly, the secondary production in the Eastern Mediterranean persisted in winter, and finally, strong primary traffic emissions dominated the primary biogenic emissions.Finally, the emission ratios were used to evaluate the global anthropogenic emission inventories downscaled to Lebanon. Although limited to two individual non-lumped species (formaldehyde and acetone), the emission ratios compared well, within a factor of 2. However, the emissions of aldehydes and ketones from the CAMS, Edgar, and MACCITY inventories showed discrepancies of up to three orders of magnitude. This demonstrates a need for improved OVOC representation in emission inventories, considering the atmospheric relevance and abundance of OVOCs and their use in volatile chemical products.

Light Induced Degradation Quantification by Monitoring the VOC Output of Silicon Solar Cell Using Low-Cost Real-Time Virtual Instrumentation

Silicon-based solar cells suffer from different types of light-induced efficiency losses (can cause up to 10% loss), known as light-induced degradation (LID). Impurities, such as boron, iron, and oxygen, are common at different concentrations in these solar cells. They form active recombination defects in boron-doped mono-crystalline (Cz-Si) and multi-crystalline (mc-Si) solar cells during illumination. For the solar industry, this will lead to serious financial loss, hence the importance of inspecting and controlling the LID level accurately. Seeking to minimize the human factor and the inaccuracy that comes with it, we have proposed in this research a low-cost virtual instrumentation solution to provide a new real-time instrumentation technique for solar cell characteristics such as open circuit voltage (VOC). The virtual data acquisition system (VDAS) design is based on a low-cost Arduino board associated with MATLAB/Simulink software. Moreover, this system can collect in real time the values of solar cell outputs under prolonged illumination and under different temperatures of the LID test. Further, kinetic modeling of the solar cell output VOC variation as a function of light soak duration; shows the predominance of one type metastable defect over the LID test of c-Si solar cells. Additionally, degradation mechanism in mc-Si solar cells involve more than one metastable defect and are more complexes due to the mc-Si substrate elaboration technique compared to c-Si substrate. Furthermore, the temperature dependence of the concentrations (NVoc) and the thermal activation energies of the defects have been extracted from the experimental VOC measurements obtained using the VDAS. Finally, the system minimizes the test period and errors for solar cell characterization compared to traditional approaches.

Real Time AMC Monitoring with Novel Chemical Ionization Mass Spectrometry at Single-Digit pptv Concentrations

In this study, emissions of photoresist resin deposited on wafters in a FOUP are compared using impinger/GCMS at-line measurements and on-line Vocus AMC measurements based on chemical ionization mass spectrometry. While GCMS measurements are routinely used for VOC measurements, the Vocus AMC monitor allows simultaneous, real-time detection of acids, bases, and condensable organics, providing unique insights into the cleanroom and FOUP microenvironment Photoresist resin outgassing measurements show comparable absolute concentrations between the two methods (GCMS and CI-TOF) for targeted compounds in real world sampling scenarios. The rate of outgassing was tracked in real time with the Vocus and also allowed identification of unknown compounds emitted from the resin. Continuous monitoring of the cleanroom air around the FOUP highlights the importance of the cleanroom environment which can directly affect the FOUP microenvironment, and additionally we show that Entegris Barrier Material EBM can guarantee a good wafer protection.

A signature of aged biogenic compounds detected from airborne VOC measurements in the high arctic atmosphere in March/April 2018

During the PAMARCMiP 2018 campaign (March and April 2018) a proton-transfer-reaction mass spectrometer (PTR-MS) was deployed onboard the POLAR 5 research aircraft and sampled the high Arctic atmosphere under Arctic haze conditions. More than 100 compounds exhibited levels above 1 pmol/mol in at least 25% of the measurements. We used acetone mixing ratios, ozone concentrations, and back trajectories to identify periods with and without long-range transport from continental sources. During two flights, surface ozone depletion events (ODE) were observed that coincided with enhanced levels of acetone, and methylethylketone, and ice nucleating particles (INP).Air masses with continental influence contained elevated levels of compounds associated with aged biogenic emissions and anthropogenic pollution (e.g., methanol, peroxyacetylnitrate (PAN), acetone, acetic acid, methylethylketone (MEK), proprionic acid, and pentanone). Almost half of all positively detected compounds (>100) in the high Arctic atmosphere can be associated with terpene oxidation products, likely produced from monoterpenes and sesquiterpenes emitted from boreal forests. We speculate that the transport of biogenic terpene emissions may constitute an important control of the High Arctic aerosol burden. The sum concentration of the detected aerosol forming vapours is ∼12 pmol/mol, which is of the same order than measured dimethylsulfide (DMS) mixing ratios and their mass density corresponds to approximately one fifth of the measured non-black-carbon particles.

An Observational Constraint of VOC Emissions for Air Quality Modeling Study in the Pearl River Delta Region

AbstractVolatile organic compounds (VOCs) have crucial influences on atmospheric chemistry. Accurate quantification of the VOC emissions is critical for air pollution research, especially when applying to air quality models. However, current bottom‐up emission inventories have biases, making observational constraints of VOC emissions necessary. We conducted concurrent VOC measurements in the Pearl River Delta (PRD) region during the summer of 2018 and found large discrepancies in the spatiotemporal variations of VOCs between observations and model simulations when using the priori VOC emission inventory (Multi‐resolution Emission Inventory for China). The normalized biases of total VOC concentrations ranged from −55% to 85% across the PRD cities in the study period. To improve the simulations, we constrained the anthropogenic VOC emissions based on their measured concentrations. The observation‐constrained VOC emissions showed clear diurnal variations and resolved the spatially‐concentrated priori emissions by reducing the high emissions by 15%–36% in the central PRD cities while elevating the sparse emissions in other cities. After employing the observation‐constrained VOC emissions, the model better reproduced the spatiotemporal variations of VOCs in the PRD region, alleviating the biases to −13%–13%. Furthermore, simulations of peak ozone (O3) concentrations were amended to reduce the mean normalized bias by 5%–12% on high O3 days. Our work has effectively combined VOC field measurements with air quality modeling to achieve better simulations of VOCs and O3. Besides, the observational‐constrained emissions are flexible for studying short‐term emission changes and their subsequent impacts on air quality.

Methylammonium-free co-evaporated perovskite absorbers with high radiation and UV tolerance: an option for in-space manufacturing of space-PV?

With a remarkable tolerance to high-energetic radiation and potential high power-to-weight ratios, halide perovskite-based solar cells are interesting for future space PV applications. In this work, we fabricate and test methylammonium-free, co-evaporated FA0.7Cs0.3Pb(I0.9Br0.1)3 perovskite solar cells that could potentially be fabricated in space or on the Moon by physical vapor deposition, making use of the available vacuum present. The absence of methylammonium hereby increased the UV-light stability significantly, an important factor considering the increased UV proportion in the extra-terrestrial solar spectrum. We then tested their radiation tolerance under high energetic proton irradiation and found that the PCE degraded to 0.79 of its initial value due to coloring of the glass substrate, a typical problem that often complicates analysis. To disentangle damage mechanisms and to assess whether the perovskite degraded, we employ injection-current-dependent electroluminescence (EL) and intensity-dependent VOC measurements to derive pseudo-JV curves that are independent of parasitic effects. This way we identify a high radiation tolerance with 0.96 of the initial PCE remaining after 1 × 1013 p+ cm-2 which is beyond today's space material systems (<0.8) and on par with those of previously tested solution-processed perovskite solar cells. Together our results render co-evaporated perovskites as highly interesting candidates for future space manufacturing, while the pseudo-JV methodology presents an important tool to disentangle parasitic effects.

Deciphering the Role of Hole Transport Layer HOMO Level on the Open Circuit Voltage of Perovskite Solar Cells

AbstractWith the rapid development of perovskite solar cells, reducing losses in open‐circuit voltage (Voc) is a key issue in efforts to further improve device performance. Here it is focused on investigating the correlation between the highest occupied molecular orbital (HOMO) of device hole transport layers (HTLs) and device Voc. To achieve this, structurally similar HTL materials with comparable optical band gaps and doping levels, but distinctly different HOMO levels are employed. Using light‐intensity dependent Voc and photoluminescence measurements significant differences in the behavior of devices employing the two HTLs are highlighted. Light‐induced increase of quasi‐Fermi level splitting (ΔEF) in the perovskite layer results in interfacial quasi‐Fermi level bending required to align with the HOMO level of the HTL, resulting in the Voc measured at the contacts being smaller than the ΔEF in the perovskite. It is concluded that minimizing the energetic offset between HTLs and the perovskite active layer is of great importance to reduce non‐radiative recombination losses in perovskite solar cells with high Voc values that approach the radiative limit.

Top Stack Optimization for Cu2BaSn(S, Se)4 Photovoltaic Cell Leads to Improved Device Power Conversion Efficiency beyond 6%

AbstractEarth‐abundant and air‐stable Cu2BaSnS4−xSex (CBTSSe) and related thin‐film absorbers are regarded as prospective options to meet the increasing demand for low‐cost solar cell deployment. Devices based on vacuum‐deposited CBTSSe absorbers have achieved record power conversion efficiency (PCE) of 5.2% based on a conventional device structure using CdS buffer and i‐ZnO/indium tin oxide (ITO) window layers, with open‐circuit voltage (VOC) posing the major bottleneck for improving solar cell performance. The current study demonstrates a &gt;20% improvement in VOC (from 0.62 to 0.75 V) and corresponding enhancement in PCE (from 5.1% to 6.2% without antireflection coating; to 6.5% with MgF2 antireflection coating) for solution‐deposited CBTSSe solar cells. This performance improvement is realized by introducing an alternative successive ionic layer adsorption and reaction‐deposited Zn1−xCdxS buffer combined with sputtered Zn1−xMgxO/Al‐doped ZnO window/top contact layer, which offers lower electron affinities relative to the conventional CdS/i‐ZnO/ITO stack and better matching with the low electron affinity of CBTSSe. A combined experimental (temperature‐ and light intensity‐dependent VOC measurements) and device simulation (SCAPS‐1D) evaluation points to the importance of addressing relative band offsets for both the buffer and window layers relative to the absorber in mitigating interfacial recombination and optimizing CBTSSe solar cell performance.

Fate of the nitrate radical at the summit of a semi-rural mountain site in Germany assessed with direct reactivity measurements

Abstract. The reactivity of NO3 plays an important role in modifying the fate of reactive nitrogen species at nighttime. High reactivity (e.g. towards unsaturated volatile organic compounds – VOCs) can lead to formation of organic nitrates and secondary organic aerosol, whereas low reactivity opens the possibility of heterogeneous NOx losses via the formation and uptake of N2O5 to particles. We present direct NO3 reactivity measurements (kNO3) that quantify the VOC-induced losses of NO3 during the TO2021 campaign at the summit of the Kleiner Feldberg mountain (825 m, Germany) in July 2021. kNO3 was on average ∼0.035 s−1 during the daytime, ∼0.015 s−1 for almost half of the nights and below the detection limit of 0.006 s−1 for the other half, which may be linked to sampling from above the nocturnal surface layer. NO3 reactivities derived from VOC measurements and the corresponding rate coefficient were in good agreement with kNO3, with monoterpenes representing 84 % of the total reactivity. The fractional contribution F of kNO3 to the overall NO3 loss rate (which includes an additional reaction of NO3 with NO and photolysis) were on average ∼16 % during the daytime and ∼50 %–60 % during the nighttime. The relatively low nighttime value of F is related to the presence of several tens of parts per trillion by volume (pptv) of NO on several nights. NO3 mixing ratios were not measured, but steady-state calculations resulted in nighttime values between &lt;1 and 12 pptv. A comparison of results from TO2021 with direct measurements of NO3 during previous campaigns between 2008 and 2015 at this site revealed that NO3 loss rates were remarkably high during TO2021, while NO3 production rates were low. We observed NO mixing ratios of up to 80 pptv at night, which has implications for the cycling of reactive nitrogen at this site. With O3 present at levels of mostly 25 to 60 ppbv (parts per billion by volume), NO is oxidized to NO2 on a timescale of a few minutes. We find that maintaining NO mixing ratios of, e.g., 40 pptv requires a ground-level NO emission rate of 0.33 pptv s−1 (into a shallow surface layer of 10 m depth). This in turn requires a rapid deposition of NO2 to the surface (vdNO2∼0.15 cm s−1) to reduce nocturnal NO2 levels to match the observations.

Employing 2D‐Perovskite as an Electron Blocking Layer in Highly Efficient (18.5%) Perovskite Solar Cells with Printable Low Temperature Carbon Electrode

AbstractInterface engineering and passivating contacts are key enablers to reach the highest efficiencies in photovoltaic devices. While printed carbon–graphite back electrodes for hole‐transporting material (HTM)‐free perovskite solar cells (PSCs) are appealing for fast commercialization of PSCs due to low processing costs and extraordinary stability, this device architecture so far suffers from severe performance losses at the back electrode interface. Herein, a 2D perovskite passivation layer as an electron blocking layer (EBL) at this interface to substantially reduce interfacial recombination losses is introduced. The formation of the 2D perovskite EBL is confirmed through X‐ray diffraction, photoemission spectroscopy, and an advanced spectrally resolved photoluminescence microscopy mapping technique. Reduced losses that lead to an enhanced fill factor and VOC are quantified by electrochemical impedance spectroscopy and JSC–VOC measurements. This enables reaching one of the highest reported efficiencies of 18.5% for HTM‐free PSCs using 2D perovskite as an EBL with a significantly improved device stability.

Sensitivity of total column NO2 at a marine site within the Chesapeake Bay during OWLETS-2

In coastal environments like the Chesapeake Bay, the presence of the sea/bay breeze circulation can contribute to poor air quality and makes modeling the meteorological and chemical impacts of the sea/bay breeze in air quality forecast models a challenge. The Ozone Water-Land Environmental Transition Study 2 field campaign aimed to better quantify the mechanisms affecting surface, profile, and columnar trace gas amounts between the land and water. Using HYSPLIT back trajectory modeling, the meteorological variability affecting Pandora NO2 and surface O3 was quantified. Clustered back trajectories showed that westerly and north-northwesterly winds resulted in the highest MDA8 ozone values over the study domain. An analysis of multiday ozone event, demonstrated how TROPOMI can capture the spatial variability of NO2 observed by the Pandora network, including the accumulation of NO2 over the Chesapeake Bay. VOC measurements during multiday ozone event were analyzed and sources of ozone precursors, such as a coal fire power plant, were identified. Further investigation of the surface ozone data at HMI revealed that significant amounts of ozone were maintained over the Chesapeake Bay at night. Using a combination of ozone lidar, Pandora, in situ O3 and NO2, and wind lidar measurements, a lofted plume of NO2 was detected over water. Additionally, the same suite of observations found significant differences in the horizontal and vertical extent of ozone on the highest exceedance day of the event. Surface measurements of trace gases (NO2 and O3) can vary significantly from remote sensing (Pandora, TROPOMI, O3lidar), highlighting the need for sensitive profile, columnar, and in situ measurements in complex urban, marine environments for future geostationary air quality validation.

Hot-Air Treatment-Regulated Diffusion of LiTFSI to Accelerate the Aging-Induced Efficiency Rising of Perovskite Solar Cells.

Perovskite solar cells (PSCs) with LiTFSI-doped Spiro-OMeTAD as the hole transport layer (HTL) generally require aging in the air to achieve high efficiency (a.k.a. aging-induced efficiency rising), but attention is rarely paid to the synergistic effects of temperature and humidity during the ambient aging. In this work, based on the understanding of the doping mechanism of Spiro-OMeTAD, we develop an ambient condition-controlled hot-air treatment (HAT) for such kinds of PSCs to further improve the device efficiency and relieve the photocurrent hysteresis. After storing the PSCs at a temperature of 35-40 °C and humidity of 35-40% RH for 30 min, efficient redistribution of LiTFSI in Spiro-OMeTAD enables much-increased conductivity due to the increased concentration of Spiro-OMeTAD+·O2- and Spiro-OMeTAD+·TFSI-, leading to an enhanced fill factor. From the light intensity-dependent Voc and capacitance-voltage measurements, the Voc enhancement is proven to be originated from the change in dominant recombination type from trap-assisted interfacial recombination to bulk Shockley-Read-Hall recombination and the improved carrier dynamics at the perovskite/HTL interface. Furthermore, the decreased density and migration of shallow-level charge traps result in the negligible hysteresis of treated devices. Our work provides new insights into the effect of ambient aging on PSCs with Spiro-OMeTAD and reveals the potentials of HAT to improve the device performance.

Monocrystalline 1.7-eV MgCdTe solar cells

Monocrystalline 1.7 eV Mg0.13Cd0.87Te/MgxCd1−xTe (x &amp;gt; 0.13) double heterostructure (DH) solar cells with varying Mg compositions in the barrier layers are grown by molecular beam epitaxy. A Mg0.13Cd0.87Te/Mg0.37Cd0.63Te DH solar cell featuring abrupt interfaces between barriers and absorber and the addition of a SiO2 anti-reflective coating demonstrate open-circuit voltage (VOC), short-circuit current density (JSC), fill factor (FF), and device active-area efficiencies up to 1.129 V, 17.3 mA/cm2, 77.7%, and 15.2%, respectively. The VOC and FF vary oppositely with the MgxCd1−xTe barrier height, indicating an optimal design of the MgCdTe DHs as a trade-off between carrier confinement and carrier transport. Temperature-dependent VOC measurements reveal that the majority of carrier recombination in the devices occurs outside the DHs, in the a-Si:H hole-contact layer, and at the interface between the a-Si:H layer and the MgxCd1−xTe top barrier at room temperature. Simulation results for the device with the highest efficiency show that the p-type a-Si:H layer and the Mg0.37Cd0.63Te top barrier contribute 1.3 and 2.4 mA/cm2 JSC loss, respectively.

Reconciling Observed and Predicted Tropical Rainforest OH Concentrations

AbstractWe present OH observations made in Amazonas, Brazil during the Green Ocean Amazon campaign (GoAmazon2014/5) from February to March of 2014. The average diurnal variation of OH peaked with a midday (10:00–15:00) average of 1.0 × 106 (±0.6 × 106) molecules cm−3. This was substantially lower than previously reported in other tropical forest photochemical environments (2–5 × 106 molecules cm−3) while the simulated OH reactivity was lower. The observational data set was used to constrain a box model to examine how well current photochemical reaction mechanisms can simulate observed OH. We used one near‐explicit mechanism (MCM v3.3.1) and four condensed mechanisms (i.e., RACM2, MOZART‐T1, CB05, CB6r2) to simulate OH. A total of 14 days of analysis shows that all five chemical mechanisms were able to explain the measured OH within instrumental uncertainty of 40% during the campaign in the Amazonian rainforest environment. Future studies are required using more reliable NOx and VOC measurements to further investigate discrepancies in our understanding of the radical chemistry in the tropical rainforest.

Influence of charge transporting layers on ion migration and interfacial carrier recombination in CH3NH3PbI3 perovskite solar cells

Using the transient Sun–Voc measurements it has been demonstrated that not only ion migration but charge accumulation/recombination at perovskite/charge transporting layer interfaces also plays a significant role in the hysteresis of J-V curves in perovskite solar cells. The transient ideality factor was investigated for two different architectures of perovskite devices. The wide range variation of transient ideality-factor implies that different ionic distribution causes change in recombination mechanisms. Owing to the passivation effect induced by PCBM, the iodine ions/vacancies were significantly reduced. These findings indicate the importance of efficient charge transfer and reduction of defects/ion accumulation at interfaces for device stability.

Over 15% efficient wide-band-gap Cu(In,Ga)S2 solar cell: Suppressing bulk and interface recombination through composition engineering

Over 15% efficient wide-band-gap Cu(In,Ga)S2 solar cell: Suppressing bulk and interface recombination through composition engineering

Investigation of the Selectivity of Carrier Transport Layers in Wide‐Bandgap Perovskite Solar Cells

Excellent contact passivation and selectivity are prerequisites to realize the full potential of high‐material‐quality perovskite solar cells, first to maximize the internal voltage (or quasi‐Fermi‐level separation) iV within the absorber, then to translate this high internal voltage into a high external voltage V. Experimental quantification of contact passivation and selectivity is, thus, key to improving device performance. Here, open‐circuit measurements of iVoc and Voc, combined with surface photovoltage measurements, are used to systematically quantify the passivation—using iVoc as a metric—and the selectivity—defined as Soc = Voc/iVoc—of a range of common carrier transport layers to wide‐bandgap (1.67 eV) perovskite absorbers. The resulting solar cells suffer from large voltage deficits, particularly when NiOx is used as the hole transport layer, even though it provides better passivation than its polymer‐based counterparts (PTAA and PTAA/PFN). This indicates a poor selectivity of NiOx (Soc &lt; 0.81 for NiOx‐based devices), whereas devices using polymer‐based hole transport layers exhibit high selectivity (Soc = 0.94–0.95). In agreement with recent reports, this low selectivity is attributed to the formation of an interlayer of non‐perovskite material with high resistance to holes at the perovskite/NiOx interface. These measurements also imply that the selectivity of the C60‐based electron transport layers is relatively good.

Behind the Breakthrough of the ∼30% Perovskite Solar Cell

In the December 11, 2020 issue of Science, Al-Ashouri and colleagues reported a certified monolithic perovskite/silicon tandem solar cell with the power conversion efficiency 29.15%. The improvements of the ideality factor and the fill factor are key to achieving efficient perovskite tandem solar cells, which lead a new direction of the perovskite research.

Using Monovalent- to Trivalent-Cation Hybrid Perovskites for Producing High-Efficiency Solar Cells: Electrical Response, Impedance, and Stability

Solar cells based on Organometal halide perovskites have emerged recently as the most promising technology for high efficiency. During the last years, innovative film processings have been developed for increasing the devices performances and stability. The two most fruitful have been (i) to complexify the perovskite composition by mixing monovalent cations and (ii) to add additives in the precursor solution which are eliminated upon the film annealing and post-deposition processing step. In the present work, perovskite films varying in their monovalent cation content, from one to three (MAPbI3, Cs0.08FA0.80MA0.12Pb(I0.88Br0.12)3 and FA1-xMAxPbI3) and optimized to reach high efficiency up to 22.2 % have been thoroughly compared for their steady-state and impedance electrical responses. Much information has been extracted from the electrical impedance spectroscopy data after their fitting by equivalent electrical circuits. With the help of complementary measurements (photoluminescence, scanning electron microscopy, Voc measurements…), the spectral features have been assigned D. Zheng, T. Zhu, Th. Pauporte ACS Appl. Energy Mater. (2020) DOI/10.1021/acsaem.0c00884 2 to physical phenomena. The relative permittivities of MAPI, CsFAMA and FAMA have been extracted from the high-frequency capacitance C2. The high-frequency resistance R2 has been related to the slow lifetime of the time-resolved photoluminescence and assigned to the bulk recombination resistance of the perovskite. The low-frequency resistance R4 has been assigned to recombinations occurring at and near the interfaces. The Low-frequency capacitance C4 has been related to the J-V curves hysteresis and assigned to recombinations. Recombination in PSC is phase delayed due to the dynamics of ions and related defect formation. It induces an imaginary component in the impedance spectra that is analyzed as C4. Overall, the (ii) strategy of mediating the growth of FA1-xMAxPbI3 perovskite double cation by additive is found the best to suppress recombinations, suppress ion mobility, reach high efficiency with low hysteresis and stabilize the perovskite compound.

Heteroleptic Tin-Antimony Sulfoiodide for Stable and Lead-free Solar Cells

Summary The quaternary chalcogenide halides of group IV and V elements have attracted much attention due to their interesting semiconducting properties as well as a suitable band gap for solar cells. Here, for the first time, we report on solar cells using tin-antimony sulfoiodide (Sn2SbS2I3). Sn2SbS2I3 solar cells were fabricated using a chemical single-step deposition process with a solution containing a SbCl3-thiourea complex and SnI2 with the configuration of TiO2 and poly[2,6-(4,4-bis(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b′]dithiophene)-alt-4,7-(2,1,3-enzothiadiazole)] as the electron- and hole-transporting layers, respectively. The best-performing cell exhibits a power conversion efficiency of 4.04% under the illumination of standard AM 1.5G conditions (100 mW cm−2). These unencapsulated cells exhibited good stabilities at 80% relative humidity, 85°C in air, and under illumination, respectively. These results provide guidelines for fabrication of lead-free heteroleptic perovskite solar cells by hosting divalent or combinations of monovalent and trivalent metal cations.