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Screening for sensitive toxicological indicators and understanding algal tolerance to pharmaceutical contaminants (PhCs) are essential for assessing PhCs risk and their removal by microalgae. Carbamazepine (CBZ) showed adverse effects on microalgae, but the specific toxicity mechanisms on the most sensitive algal photosynthetic system (PS) remain limited. This study delved into the impact of CBZ exposure on the growth, cell viability, pigment content, and PS of Chlorella vulgaris. The findings revealed a notable inhibition of C. vulgaris growth by CBZ, with an IC 50 value of 27.2 mg/L at 96 h. CBZ exposure induced algal membrane damage and cell viability. Intriguingly, CBZ drastically diminished intracellular pigment levels, notably showing "low promotion and high inhibition" of chlorophyll b (Chl b) by 72 h. Moreover, the study identified a decreased number of active reaction centers (RCs) within algal PSII alongside inhibited electron transport from Q A to Q B on the PSII receptor side, leading to PSII disruption. As an adaptive response to CBZ stress, C. vulgaris stimulated its Chl b synthesis, increased non-photochemical quenching (NPQ), and adapted its tolerance to bright light. Additionally, the alga attempted to compensate for the CBZ-induced reduction in electron transfer efficiency at the PSII receptor side and light energy utilization by increasing its electron transfer from downstream. Principal component analysis (PCA) further verified that the parameters on non-photochemical dissipation, electron transport, and integrative performance were the most sensitive algal toxicological indicators for CBZ exposure, and algal PS has energy protection capability through negative feedback regulation. However, prolonged exposure to high doses of CBZ will eventually result in permanent damage to the algal PS. Hence, attention should be paid to the concentration of CBZ in the effluent and the exposure time, while methods to mitigate algal photodamage should be appropriately sought for algal treatment of dense effluents. [Display omitted] • CBZ inhibited algal growth, compromised cell viability and pigments level. • CBZ decreased RCs number and inhibited electron transport on PSII receptor side. • CBZ enhanced electron transfer from downstream as a compensation. • PCA results revealed the most sensitive algal toxicological indicators. • Algal PS has energy protection capability through negative feedback regulation. [ABSTRACT FROM AUTHOR]

The aqueous-based Zn-ammine complex solutions represent one of the most promising routes to obtain the ZnO electron transport layer (ETL) at a low temperature in inverted organic solar cells (OSCs). However, to dope the ZnO film processed from the Zn-ammine complex solutions is difficult since the introduction of metal ions into the Zn-ammine complex is a nontrivial process as ammonium hydroxide tends to precipitate metal salts due to acid-base neutralization reactions. In this paper, we investigate the inverted OSCs with Al-doped-ZnO ETL made by immersion of metallic Al into the Zn-ammine precursor solution. The effects of ZnO layer with different immersion time of Al on film properties and solar cell performance have been studied. The results show that, with the Al-doped-ZnO ETL, an improvement of the device performance could be obtained compared with the device with the un-doped ZnO ETL. The improved device performance is attributed to the enhancement of charge carrier mobility leading to a decreased charge carrier recombination and improved charge collection efficiency. The fabricated thin film transistors with the same ZnO or AZO films confirm the improved electrical characteristics of the Al doped ZnO film. [ABSTRACT FROM AUTHOR]

Titanium oxide (TiOx) modified with a thin layer of Al was used as an electron transporting layer in an inverted organic solar cell based on the P3HT/PCBM blend. The thin Al layer was shown to improve the TiOx surface properties, decreased the work-function of TiOx, increased the built-in voltage, and facilitated electron extraction. As a result, good device performance with power conversion efficiency of 3.6%, open circuit voltage of 0.60 V, short circuit current of 9.13 mA/cm2, and fill factor of 0.66 was achieved. The light soaking problem was eliminated compared to the TiOx only device. [ABSTRACT FROM AUTHOR]

The charge transport layer is crucial to the performance and stability of the perovskite solar cells (PSCs). Compared with other conventional metal oxide electron transport materials, SnO2 has a deeper conduction band and higher electron mobility, and can efficiently serve as an electron transport layer to facilitate charge extraction and transfer. Herein, an optimized low‐temperature solution‐processed SnO2 electron transport layer is achieved by doping polyethylenimine polyelectrolyte into SnO2 for the first time in the PSCs. It is found that the performance of all aspects of the doped SnO2 film is improved over that of the pristine SnO2 film. The better energy level alignment, larger built‐in field, enhanced electron transfer/extraction, and reduced charge recombination all contribute to the improved device performance. Finally, a PSC with a power conversion efficiency of 20.61% is successfully prepared under low temperature below 150 °C. Moreover, the stability of the doped SnO2‐based device is also greatly improved. [ABSTRACT FROM AUTHOR]

Understanding the interfacial properties of perovskite/SnO2 interface is important for perovskite solar cell design and optimization. Here, interfacial structure and transport properties of CH3NH3PbI3/SnO2 interfaces are investigated comprehensively by density functional theory and experiment. Forming CH3NH3PbI3/SnO2 interfaces weakens the gap states induced by CH3NH3PbI3 surfaces. The interfacial transport properties are strongly dependent on the interface atomic configurations. The CH3NH3PbI3/SnO2 interface with PbI and O terminations is more beneficial for hole blocking and electron transporting due to the largest valence band offset compared to the CH3NH3PbI3/SnO2 interface with other terminations. Moreover, it exhibits a larger electrostatic potential difference compared with CH3NH3PbI3/TiO2 interface, leading to the higher electron transfer efficiency. Hence, higher power conversion efficiency is achieved based on CH3NH3PbI3/SnO2 compared to CH3NH3PbI3/TiO2 structure in experiments. In addition, CH3NH3PbI3/SnO2 interfaces with PbI terminations are more stable than those with CH3NH3I terminations, suggesting PbI2 layer may be preferentially formed on SnO2 substrate during CH3NH3PbI3 fabrication process. Such results could provide a useful understanding on CH3NH3PbI3/SnO2 interface and contribute to new strategies for the interface optimization. [ABSTRACT FROM AUTHOR]

ZnO is considered as a potential electron transport layer (ETL) in solar cells due to its high charge carrier mobility and low‐temperature processability. However, it is challenging to obtain highly efficient and stable perovskite solar cells (PSCs) using low‐temperature ZnO ETL due to the poor chemical compatibility between ZnO and perovskite films. Hence, proper surface passivation strategies of ZnO ETL are developed to enhance the ZnO/perovskite interface stability for highly efficient PSCs. In this study, low‐temperature TiOx post‐treatment is performed to passivate the ZnO surface, suppress the interface charge recombination, and stabilize the ZnO/perovskite interface. The fullerene treatment is further applied to enhance the electron transfer from perovskite to ZnO and reduce the hysteresis behavior. Finally, high‐performance PSCs with an efficiency of over 20% and improved stability are achieved. [ABSTRACT FROM AUTHOR]

We present that atomic layer deposition (ALD) of TiO 2 thin layer on SnO 2 electron transport layer (ETL) could simultaneously boost the crystallization control of CsPbIBr 2 absorber film and band alignment of all-inorganic perovskite solar cell (PSC). The former awards the desired CsPbIBr 2 film characterized by high crystallinity, weak halide phase separation, as well as extremely uniform- and large-sized grains. And, the latter brings a cascade pathway for electron extraction and transport in the cell. Such combined morphology tailoring and interface engineering are extremely beneficial to suppress both bulk recombination and interfacial recombination of charge carrier. As a result, the cell' efficiency can be boosted from 6.11% to 9.31%, which is beyond all the pure CsPbIBr 2 -based PSCs reported to date. Therefore, our works highlight the dual functions of ALD-processed TiO 2 interfacial layer in processing high-performance all-inorganic PSC. Atomic layer deposition (ALD) of TiO 2 thin layer on SnO 2 electron transport layer could simultaneously boost the crystallization control of CsPbIBr 2 absorber film and band alignment of all-inorganic perovskite solar cell. Thus, the cell efficiency can be boosted from 6.11% to the record-high value of 9.31%. Image 1 • ALD-processed TiO 2 on SnO 2 ETL triggers dual functions of crystallization control and band alignment in CsPbIBr 2 PSC. • Crystallization control enables high crystallinity, weak phase separation, and uniformly large-sized grains in CsPbIBr 2 film. • Band alignment facilitates a cascade pathway for electron extraction and transport. • The dual functions of TiO 2 thin layer boost efficiency of pure CsPbIBr 2 -based cell to the record-high value of 9.31%. [ABSTRACT FROM AUTHOR]

• TiO 2 electron transport layer deposited by ALD at about 150 °C. • SnO 2 /PCBM double modifier at TiO 2 /perovskite interface. • Low-temperature processed perovskite solar cells with a PCE of 19.45%. • Enhanced performance compared to devices with solution processed TiO 2. Perovskite solar cells (PSCs) have attracted increasing attentions for their outstanding efficiency and simple fabrication process. However, the commonly used typical titanium dioxide (TiO 2) electron transport layer (ETL) requires a high-temperature treatment to crystallize. In this work, the low-temperature (150 °C) atomic layer deposition (ALD) processed TiO 2 ETL, and the SnO 2 /PCBM double interfacial modifier have been adopted to fabricate the high performance PSCs of ITO/ALD-TiO 2 /SnO 2 /PC 61 BM/MA 0.7 FA 0.3 PbI (3-x) Cl (x) /Spiro-OMeTAD/Ag. The measurement results show that the PSCs with ALD-TiO 2 ETL obtain the higher champion PCE of 19.45% than that of PSC with solution-TiO 2 ETLs (PCE = 18.64%), along with the obviously enhanced FF and V OC , as well as the better light stability and repeatability. And the transient photocurrent and photovoltage results demonstrate that the performance improvement origins from the enhanced charge transport and suppressed charge recombination. Therefore, the low-temperature ALD-TiO 2 ETL with suitable modification is a promising strategy to fabricate efficient PSCs and flexible devices. [ABSTRACT FROM AUTHOR]

• An effective SnO 2 :InCl 3 composite is used as ETL for planar perovskite solar cells. • Cl ions can passivate the defects on the SnO 2 surface and perovskite grain boundaries. • In ions themselves are suitable dopants and can provide better doping performance for SnO 2. • The simultaneous ETL doping and interface passivation result in a significant enhanced PCE and short-circuit current density. There are many defect states at the interface between SnO 2 and perovskite due to the preparation process and the lattice mismatch. These defects will trap photo-generated carriers, resulting in low carrier extraction efficiency and loss of device stability. Many researches are underway to further improve the performance of perovskite solar cells (PSCs) based on SnO 2 electron transport layer (ETL), including doping of ETL and effective passivation of interface defects. Here, the SnO 2 :InCl 3 ETL is used in planar perovskite solar cells to simultaneously dope ETL and passivate the defects at the ETL/perovskite interface. First, Cl ions can passivate the defects on the SnO 2 surface, and part of the chloride ions can also diffuse into the perovskite to passivate the grain boundaries. Additionally, In ions themselves are suitable dopants and can provide better doping performance for SnO 2. The result shows that the simultaneous ETL doping and interface passivation result in a significant increase of PCE from 19.1% to 20.8% due to the enhancement of short-circuit current density. This method expands the ETL/perovskite interface optimization work by using anions and cations for passivation and doping, respectively, and has some inspiration for the delivery of high efficiency and stable planar structure PSCs based on SnO 2 ETL. [ABSTRACT FROM AUTHOR]

Many recent studies have shown that perovskite solar cells (PSCs) employing SnO 2 as an electron transport layer (ETL) exhibit extremely high efficiency which is close to that of the device with the same structure using TiO 2. Considering the sensitivity of the PSC performance to the ETL/perovskite interface, interface engineering of the SnO 2 electron transport layer helps to further release the potential of planar structure PSCs and promote their commercialization. Herein, we introduce an amino acid self-assembled layer onto the SnO 2 ETL as the buffer layer to modulate the SnO 2 /perovskite lattice mismatch induced interface stress, and enhanced the interface interaction between SnO 2 and perovskite caused by hydrogen-bonding and/or electrostatic interactions between the amino groups and the perovskites framework. Due to the improved perovskite film quality and enhanced interface charge transfer/extraction, a champion efficiency of 20.68% (J sc = 24.15 mA/cm2, V oc = 1.10 V, and FF = 0.78) is obtained for Cs 0.05 MA y FA 0.95-y PbI 3-x Cl x planar PSCs. • The amino acid buffer layer as the buffer layer is introduced on SnO 2 ETL. • The interface interaction between SnO 2 and perovskite is enhanced. • The buffer layer enhances the charge transfer and collection at interface. • High efficiency perovskite solar cells over 20% and good stability are achieved. [ABSTRACT FROM AUTHOR]

• Graphene quantum dots (GQDs) are used to modify the SnO 2 ETL in perovskite solar cells. • The GQDs increase the electronic coupling as well as energy levels matching between the perovskite and SnO 2 ETL. • The combination of SnO 2 :GQDs leads to a significant improvement of efficient charge carrier extraction and suppression of the charge recombination. • A high PCE of 21.1% is obtained, which is increased by 13.4% in comparison with the device based on the SnO 2 -only ETL (18.6%). In this work, Graphene quantum dots (GQDs) was decorated on the SnO 2 electron transport layers (ETLs) to boost the performance of perovskite solar cells (PSCs). The power conversion efficiency (PCE) of 21.1% was acquired with the combination of SnO 2 and GQDs. Compared with the SnO 2 -only ETL devices (18.6%), the PCE of SnO 2 /GQDs based devices is greatly enhanced in PCE by the value of 13.4% as well as in the stability. Investigation reveals that with the combination of SnO 2 and GQDs, the open circuit voltage (V OC) and the short circuit current density (J SC) could increase. Various advanced optical and electrical characterizations were carried out to explore the action mechanism of GQDs. The experimental results convinced that the introduction of GQDs leads to the better carrier transportation and extraction by increasing the electronic coupling and matching the energy levels between the perovskite and SnO 2 ETL. Also, the perovskite film quality deposited on the GQDs decorated SnO 2 ETL is better compared with the SnO 2 only. Furthermore, the device stability based on the GQDs modified SnO 2 is evidently improved contrast to the SnO 2 -only device. Its performance kept above 80% of initial value after 720 h storage. [ABSTRACT FROM AUTHOR]

Planar halide perovskite solar cells (PSCs) have undergone rapid development in last decade due to their excellent optoelectronic properties. An electron transport layer (ETL) with high electron mobility is crucial to achieve high power conversion efficiency (PCE). TiO 2 is one of the most common ETLs in n-i-p planar PSCs. But the low electron mobility and high annealing temperature of TiO 2 hamper the device performance and applications. In 2 O 3 has a higher electron mobility and wider bandgap compared with TiO 2 ETL. Herein, we report a low-temperature combustion synthesized In 2 O 3 as ETL for PSCs. The electron mobilities of In 2 O 3 films are investigated by the thin film transistors (TFTs) under annealing at different temperatures. By optimizing the In 2 O 3 layer, a power conversion efficiency of 18.12% is obtained, and is among the highest values for PSCs based on In 2 O 3 ETL. Meanwhile, the unencapsulated devices exhibit a remarkable stability, retaining 75% of the initial value after over 120 days' storage. Image 1 • Low temperature combustion synthesized In 2 O 3 was used as electron transport layer. • The In 2 O 3 layer exhibited high electron mobility for thin film transistors. • The In 2 O 3 layer enhanced the charge transfer and collection at interface. • High efficiency perovskite solar cells over 18% and good stability were achieved. [ABSTRACT FROM AUTHOR]