Search

[Display omitted] • Stretchable PPy-based organohydrogel (POG) with anti-freezing properties was synthesized through a facile sol–gel method. • The POG exhibits an exceptional shielding effectiveness (SE T) of 63.6 dB with a thickness of only 2.0 mm. • After being frozen at − 40 ℃ for 4 h, POG still possesses an excellent shielding capability of 59.3 dB. Wearable and multi-functional electromagnetic interference (EMI) shielding materials are an inevitable trend in order to cope with increasingly complex practical applications. In the present work, polypyrrole nanotube (PNT)-based organohydrogels (POGs) with excellent electromagnetic shielding effectiveness (SE) were synthesized through a facile sol–gel strategy. The obtained POGs offer distinct shielding performance, anti-drying, anti-freezing, plasticity and recyclable ability. The POG with a 20 wt% PNTs filling exhibits a SE T of 63.6 dB in the X-band at a thickness of 2.0 mm. After being placed at ambient temperature for 30 days and − 40 ℃ for 4 h, its SE values still retained at 50.3 dB and 59.3 dB, respectively. Moreover, after being immersed in the solvents, the POG (left in the air for 30 days) can recover flexibility and 92 % of its original EMI shielding performance. Importantly, crushing the fully dried organohydrogels into the powder and placing it again in the solvents fully restores its flexibility and EMI shielding properties. The glorious shielding and mechanical characteristics can be ascribed to the superior conductivity of PNTs and the highly crosslinked stable network of PVA, as well as the further enhancement of the crosslinked network by cellulose nanofibers. In addition, ​sensors based on POGs can effectively detect human movement and strain deformations. This work thus provides fresh insight into exploring the sustainability of flexible and wearable EMI shielding materials for handling extreme environments. [ABSTRACT FROM AUTHOR]

[Display omitted] • SnO{0 0 1}/TiO 2 {0 0 1} heterojunctions were rationally designed and synthesized. • The formation of S-scheme heterojunction enhances the hole mobility. • The photocatalytic degradation rate constant of benzene was boosted by 5.3 times. • The photocatalytic degradation pathways of gas benzene were proposed. • S-scheme mechanism was confirmed via theoretical and experimental results. Enhancing the efficiency of carrier migration and separation plays a pivotal role in promoting photocatalytic performance. Constructing S-scheme heterojunction is a promising strategy to achieve this desired objective. Here, we rationally designed and preciously synthesized SnO{0 0 1}/TiO 2 {0 0 1} S-scheme heterojunction with exceptionally high hole mobility (1122 cm2/(V·s)), which ranks among the best of reported works. SnO{0 0 1}/TiO 2 {0 0 1} heterojunctions exhibited outstanding performance of gaseous benzene degrading. The degradation rate constant of SnO/TiO 2 heterojunction is 2.4675 h−1, and is boosted by 5.3 times compared with TiO 2 (0.4595 h−1). Through the combination of theoretical calculation and experiment, S-scheme mode of carrier transferring was verified. The promoted hole mobility in SnO/TiO 2 heterojunction enhances the production of ·OH, further boosting photocatalytic performance. By analyzing the detected intermediates, we proposed degradation pathways for benzene, which provide a profound and elucidating view of complex processes in benzene photocatalytic degradation. [ABSTRACT FROM AUTHOR]

Direct interspecies electron transfer (DIET) is a new mechanism responsible for syntrophic methane production. Supplementation of conductive material in syntrophic communities can facilitate electron transfer and enhance methane production. Ferroferric oxide (Fe 3 O 4 ) was dosed in an anaerobic sequencing batch reactor (ASBR) fed with tryptone-based synthetic wastewater to examine its effect on the anaerobic treatment process. Long-term dosage of Fe 3 O 4 not only enhanced the maximum methane production rate by 78.3% in a reaction cycle but also improved methane production when hydrogen/carbon dioxide or acetate was used as the substrate. The conductivity of anaerobic sludge, activity of the electron transport chain, and extracellular electron transfer ability were enhanced with the addition of Fe 3 O 4 , inducing enhanced system performance for methane production. Proteiniclasticum and Prolixibacter were the enriched acidogens responsible for hydrolysis and acidification. With the addition of Fe 3 O 4 , Methanosarcina was the dominant methanogen, and metagenomic analysis further revealed the genes involved in the hydrogenotrophic pathway of methanogenesis. Methanosarcina might be involved in DIET, and Fe 3 O 4 was responsible for its stimulation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe doping via interfacial redox-precipitation method was effective to generate abundant oxygen vacancies over FeMn oxide catalysts. • Formation of abundant oxygen vacancies effectively improved oxygen species mobility and reducibility. • Rapid methyl dehydrogenation to form benzoate, and aromatic ring breakage are rate-controlling step for toluene oxidation. • Both adsorbed oxygen and lattice oxygen with improved mobility could participate in the toluene adsorption-oxidation process. • The oxygen vacancies could promote the C C breakage of aromatic ring. A series of homogenous Fe-Mn oxides with superior catalytic oxidation activity was developed via interfacial redox-precipitation method for eliminating VOCs from industrial waste gas. Among them, Fe 1 Mn 5 oxide achieved the optimum catalytic performance for toluene oxidation with a T 90 of 209 ℃. In addition, the catalyst demonstrated superior stability for long-time operation and great water resistance. By combining an array of analytical techniques with DFT calculations, the results revealed that Fe doping and interfacial redox-precipitation method synergistically resulted in high concentration of oxygen vacancy defect over Fe 1 Mn 5 oxide, which improved lattice oxygen mobility and oxygen species activity, thus enhancing its low temperature reducibility. Meanwhile, in situ DRIFTS analysis revealed that both the adsorbed oxygen species and lattice oxygen with improved mobility could interact with adsorbed toluene, thus facilitating rapid dehydrogenation of methyl and demethylation of toluene and promoting the breakage of C C bond in the aromatic ring. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bilateral passivation strategy by PEACl doping and NPB post-treatment is proposed. • Construction of GHJ provides a favorable transport pathway for hole migration. • Achieving a PCE of 21.88% for PEACl-SnO 2 -NPB based PSCs with negligible hysteresis. • Improved moisture and thermal stability of PSCs by using synchronous regulation. Defects and inferior charge transport dynamics within devices are key issues that inhibit the improvements of photovoltaic performance and stability. Developing facile and feasible strategies for synchronous passivation of defects regarding charge transport layers (CTLs), perovskite films and their interfaces, and precise tuning of energy level structure, is a definite way to solve above problems. Herein, we develop a synergistic passivation strategy for perovskite films and bilateral interfaces to improve device performance. Firstly, an appropriate amount of phenylethylammonium chloride is adopted to modify SnO 2 electron transport layer (ETL). The complexation reaction between N atoms in –NH 2 and Sn4+ improve the agglomeration of SnO 2 nanoparticles and film quality of SnO 2 ETL. The presence of Cl− ions not only effectively fill oxygen vacancies within SnO 2 ETL, but also participate in regulating crystal growth dynamics of perovskite films, thus improving electron transport properties at interface. Subsequently, p-type conducting material N,N'-Bis-(1-naphthalenyl)-N,N'-bis-phenyl-(1,1′-biphenyl)-4,4′-diamine (NPB) is introduced into anti-solvent chlorobenzene during the preparation of perovskite films to further regulate the crystal quality and achieve full-range defect passivation. Particularly, the introduction of NPB helps to construct a gradient heterojunction between upper perovskite film and SpiroOMeTAD hole transport layer, thus reducing the accumulation of hole carriers near interface and further suppressing current–voltage hysteresis behavior of devices. Additionally, the hydrophobicity of NPB and full range of defect passivation greatly enhance the humidity and thermal stability of devices. Finally, a high power conversion efficiency of 21.88% is obtained with suppressed hysteresis and enhanced long-term stability. This work highlights the role of full-range defect passivation on CTLs, perovskite absorption layers and interfacial charge transport properties, which provide a novel concept for constructing high-performance and stable perovskite devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Iodine ligand-coupled PbS QDs film was firstly used to modify ZnO ETLs to boost photovoltaic performance of PSCs. • Introducing PbS-TBAI layer improves crystal quality of perovskite and forms cascade energy band structure. • A maximum PCE of 20.53 % has been achieved in the PSCs based on ZnO/PbS-TBAI-80 ETLs. Zinc oxide (ZnO) was traditional cathode material for solar cells due to excellent photoelectric properties. However, when ZnO is used as electron transport layers (ETLs) in perovskite solar cells (PSCs), the occurred deprotonation reactions can easily lead to the decomposition of perovskite layer. Herein, we reported a simple and controllable low-temperature strategy to overcome above problem for achieving high-efficient and stable ZnO based planar PSCs, i.e. the colloidal PbS QDs and tetrabutylammonium iodide (TBAI) was sequentially spin-coated on ZnO ETLs and then mild post-annealing process was carried out to obtaining ZnO/PbS-TBAI compact layer. Due to the iodine ligands from TBAI, the PbS-TBAI films act as both surface wetting control layer and electric dipole layer to adjust the crystal growth of perovskite films and charge behavior within devices. The better non-wetting surface of ZnO/PbS-TBAI ETLs improves the crystallization of the perovskite films by suppressing heterogeneous nucleation. And the unique energy level alignment of ZnO/PbS-TBAI induced by tunable surface dipole moment of TBAI boosted hetero-interface charge extraction of PSCs. Consequently, the optimized ZnO/PbS-TBAI based PSCs exhibits the power conversion efficiency (PCE) of 20.53 %, which is the champion PCE of ZnO PSCs with MAPbI 3 as the absorption layer. Stability tests also proved that the PCE of ZnO/PbS-TBAI based PSCs remains more than 86 % after exposure to 40 % humidity for 30 days, which is much more superior to that of control device. We firstly used iodination PbS QD films in this work to achieve higher photovoltaic performance in ZnO based PSCs, which prompts the further application of QDs materials within optoelectronic devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Inorganic HAuCl 4 doping combined organic NPB post-treatment strategy was proposed. • High PCE of 19.20% for Au@PEDOT:PSS/NPB PSCs is achieved on rigid substrate. • Flexible Au@PEDOT:PSS/NPB PSCs achieve 14.04% PCE with strong wrinkle resistance. • Improved hysteresis and stability of PSCs are realized via synchronous regulation. The further improvements in optoelectronic properties, hydrophobicity of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) hole transport layers, as well as regulation of defect states within devices are essential to promote the continued development of inverted p-i-n rigid and flexible planar perovskite solar cells (PSCs). However, the strong hygroscopicity, poor surface morphology, lower work function and coil configuration of pristine PEDOT:PSS films are detrimental to their own performance and growth dynamics process of perovskites, often resulting in sever energy losses and poor device performance. Herein, hydrogen tetrachloroaurate (III) hydrate (HAuCl 4 ·3H 2 O) additive is combined with a conductive N,N'-Bis-(1-naphthalenyl)-N,N'-bis-phenyl-(1,1′-biphenyl)-4,4′-diamine (NPB) buffer layer to boost device performance by systematically modulating PEDOT:PSS and perovskite film. Wherein, the redox reaction between PEDOT:PSS and HAuCl 4 can cause phase segregation of PEDOT:PSS, improving the hydrophobicity, electrical conductivity, work function and surface morphology of the films. The reduced gold nanoparticles will produce localized surface plasmon resonance effects, thus enhancing the utilization of solar radiation by perovskite films. Furthermore, the suitable energy level alignment of NPB layer relative to perovskite and Au@PEDOT:PSS films will sufficiently exploit the dissociative excitons to facilitate effective hole transport, and the N atoms in NPB can also passivate defects at the interface by binding to uncoordinated Pb2+ ions, thereby reducing non-radiative open-circuit voltage loss and increasing short-circuit current density. A high power conversion efficiency (PCE) of 19.20% can be achieved for MA 0.85 FA 0.15 PbI 3 based p-i-n PSCs with negligible hysteresis and enhanced stability of devices. Similarly, the corresponding flexible device achieves a PCE of 14.04% with improved crumpling durability throughout low temperature preparation conditions below 140 °C. Our work presents a facile method to prepare high-efficient inverted PSCs while achieving improved long-term device stability. [ABSTRACT FROM AUTHOR]

[Display omitted] • Template-assisted electrospinning is applied to fabricate the multi-level microstructure TPU membranes. • The pressure sensor shows ultralow detection limit, high sensitivity and wide sensing range. • The building block approach is creatively applied in FEA. • The pressure sensors enable real-time human physiological signals. Geometric microengineering is an effective approach to improve the comprehensive performance of pressure sensors. Unfortunately, the design of multi-level microstructure and the development of industrially relevant technology remain challenging. In this study, template-assisted electrospinning is applied to fabricate the multi-level microstructured TPU membranes with both regularly distributed knoll-like microstructures on the surface and randomly distributed fiber-network structures inside, which serve as the active layers of the pressure sensor. The assembled pressure sensor shows exceptional performance, including ultralow detection limit of 0.7 Pa, high sensitivity of 63.93 kPa−1, a wide sensing range of 0–160 kPa and excellent durability of >10000 cycles. The sensing mechanism is further investigated based on the equivalent circuit diagram analysis and finite element analysis (FEA). In FEA, the building block approach is adopted to simulate the electro-mechanical performance between complex fiber networks. These results reveal that the knoll-like microstructures and fiber-network structures lower the effective elastic modulus and increase the contact points/areas or conductive path upon loading, thereby responsible for the exceptional sensing performance. Real-time monitoring of human physiological signals is demonstrated. The industrial relevance of the template-assisted electrospinning technology for fabricating pressure sensors is highly scalable, thus industrially relevant. [ABSTRACT FROM AUTHOR]

[Display omitted] • Natural biomaterials in flexible stretchable strain sensor applications are critically reviewed. • Three strategies based on nature-inspired structural designs for enhancing the electromechanical performance are presented. • Challenges and future perspectives of biomaterials and biostructures for flexible stretchable strain sensors are discussed. Flexible stretchable strain sensors have received tremendous attention due to their excellent performance and comfort. Material selection and structural design are considered the two essential factors for driving the development of flexible stretchable strain sensors. Due to natural biomaterials with numerous superiorities (such as unique structures, diverse chemical group, biodegradability, and environmental benignity) and biostructures with delicate and rational design principles, they have become new stars in the field of flexible stretchable strain sensors. Herein, this review systematically summarizes the state-of-the-art achievements in biomaterials and biostructures for the development of high-performance flexible stretchable strain sensors. According to the structural features of flexible stretchable strain sensors, the various roles and function of biomaterials are reviewed in detail, including as active materials, flexible substrates, and functional materials. Special attention is paid to the three most representative nature-inspired structural designs and optimization for flexible stretchable strain sensors, including crack, brick-and-mortar and wrinkled structures. The main challenges and future R&D directions for biomaterials-and biostructures- inspired flexible stretchable strain sensors are discussed. This comprehensive review and outlooks will enlighten readers to better understand the current development status and future research activities in using natural biomaterials and biostructures for the fabrication of flexible stretchable strain sensors. [ABSTRACT FROM AUTHOR]

[Display omitted] • An excellent performance nZVI heterogeneous catalyst was developed and optimized. • The enhancement mechanisms of citrate ligands to nZVI were comprehensively explored. • Citrates and their hydroxyl-rich fragments formed a special spatial network structure on nZVI surface. • A degradation mechanism different from the traditional Fenton-like reaction was proposed. Today, the steroid estrogens (SEs) discharged with non-point source pollutions have brought potential risks to the environment. It is necessary to develop new restoration strategies for SEs. In this study, a heterogeneous nano-zero-valent iron Fenton system loaded with citrate ligands (C-nZVI) was proposed. It obviously enhanced the degradation rates of 17β-estradiol (17β-E2), and the degradation efficiency under neutral condition was also enhanced by 4.59 times. The characterization of C-nZVI showed that citrates and their hydroxyl-rich fragments formed a spatial network structure and covered on its surface. This allowed C-nZVI to overcome most of the inherent defects of nZVI and had ideal abilities to resist agglomeration, acid corrosion, and oxidation. Same as the traditional Fenton-like reaction, the generation of hydroxyl radicals (·OH) and superoxide radicals (·O 2 –) was the main way for C-nZVI to degrade 17β-E2. The ligands as the ions transport channel further stimulated the excitation of ·OH and ·O 2 –, and the singlet oxygen (1O 2) was also found to play a role in the latter part of the reaction. However, C-nZVI had a special mechanism of first coupling between citrate ligands and 17β-E2, as well as subsequent degradation by ROSs, which might be the reason why C-nZVI has a much faster degradation efficiency than the general nZVI. And the degradation process of 17β-E2 showed its four rings might be destroyed one by one starting from the benzene ring. Therefore, this heterogeneous Fenton system assisted by chelating agent ligands has a certain value for the research of water emergency restoration. [ABSTRACT FROM AUTHOR]

[Display omitted] • FSMPFs applied for oil absorption underwater in irregularly shaped spaces were prepared by flash spinning. • FSMPFs have high oil adsorptions in air (76.70 g/g) and underwater (65.32 g/g). • FSMPFs show good magnetic controllability when applied to oil absorption underwater in irregularly shaped spaces. • FSMPFs have a high separation efficiency (99.6 %) for oil–water emulsion. • FSMPFs exhibit good oil adsorption performance and stability in different pH value and salinity conditions. Oil pollution in water has destructive effect on the ecological environment of water bodies. However, the treatments for oil pollution underwater in irregularly shaped and non-open environments face a challenge owing to the difficulty in driving oil absorption materials underwater. Herein, this work reports a facile strategy to prepare flash spinning magnetic polyethylene fibers (FSMPFs) for oil absorption application in irregularly shaped and non-open underwater environments. The as-prepared FSMPFs exhibit good oil absorption performance, of which the oil absorption in air and underwater is 76.70 g/g and 65.32 g/g, respectively, and the FSMPFs can maintain their oil absorption performance in environments with different salinities (1–5 %) and pH values (2–12). Also, the FSMPFs show good magnetic responsiveness and controllability when applied to oil–water separation underwater in irregularly shaped pipes, and the oil–water separation efficiency of FSMPFs for oil–water emulsion reaches 99.6 %. Besides, the FSMPFs have good mechanical properties and reusability, of which the tensile strength and elongation at break is 185.9 cN and 41.2 %, respectively, and oil absorption is 76.28 g/g (99.5 % of the initial value) after 10 cycles of absorption–desorption. The FSMPFs have great potential in practical applications for oil absorption under irregularly shaped and non-open environments. [ABSTRACT FROM AUTHOR]

• Steel slag shows immense potential for use in seawater desalination. • Carbon-coated nitrogen doping enhances light absorption and hydrophilicity. • The 3D device achieves 29.4 kg m−2h−1 evaporation at 4 m s−1 for at least 5 days. • Finite element analysis guides optimal porosity at various wind speeds. • Carbon emissions per ton of desalinated seawater are only 2.02 kg CO 2 -eq. Water scarcity and waste pollution are serious global challenges due to the rapid development of the global economy and population growth. A win–win strategy to address the water crisis and reduce pollution is to use waste materials as low-carbon and eco-friendly photothermal materials for solar-driven desalination. Steel slag, an abundant industrial waste product, has excellent thermal conductivity. Enhancing its light absorption and hydrophilicity could enable the creation of efficient and economical solar seawater desalination devices. In this study, our research introduces a 3D desalination device using this modified slag, achieving a consistent evaporation rate fluctuating around 29 kg m-2h−1 at 4 m s−1 wind speed for five days. This breakthrough can be attributed to the excellent light-to-heat conversion of the modified steel slag, coupled with the synergistic interaction between the porous evaporator and wind, culminating in efficient steam evaporation and diffusion. Life Cycle Analysis (LCA) reveals that the carbon emissions of the modified steel slag for desalinating each ton of seawater are only 2.20 kg CO 2 -eq, indicating superior prospects for carbon reduction compared to the reverse osmosis (RO) and Multi-Stage Flash Desalination (MSF) processes. [ABSTRACT FROM AUTHOR]

• We developed a "hillocks"-like random-textured perovskite (HRT-perovskite) absorber. • Crystallization kinetics and formation mechanisms of CB-induced HRT-perovskite absorbers have been proposed. • Proper volume CB promoted the construction of porous MAI-PbI 2 -DMSO intermediate structure. • Efficient light trapping was achieved by employing CB-induced HRT-perovskite absorbers. Efficient planar heterojunction perovskite solar cells (PSCs) with high-quality absorbers are promising for flexible-, semitransparent-, and tandem- photovoltaic applications. However, compared to mesoporous PSCs, planar perovskite absorbers tend to suffer from additional optical losses due to insufficient light harvesting. Accordingly, the design and fabrication of high-quality textured perovskite absorbers are promising to improve device performance. We developed a "hillocks"-like random-textured perovskite (HRT-perovskite) absorber using a facile chlorobenzene (CB) anti-solvent assisted spin-coating approach. The crystallization kinetics and formation mechanisms of CB-induced HRT-perovskite absorbers have been systematically explored, allowing us to gain insights into the role of CB, i.e. an appropriate volume of CB promotes the formation of a porous MAI-PbI 2 -DMSO intermediate structure. We show that the porous nature of the intermediate film provides sufficient space for lattice reconstruction and structure expansion during crystal growth, thus effectively improving the film and surface/interface quality, and, ultimately, the optoelectronic properties of the perovskite absorber. Moreover, the HRT-perovskite absorber exhibits excellent light-trapping capability and carrier mobility, due to its optimized surface roughness and longitudinally ordered grain boundary distribution. As a result, we obtained efficiencies of up to 20.03% from planar heterojunction PSCs fabricated using ~400 nm thick HRT-perovskite absorbers. The process exhibits very high reproducibility with 20 individual devices fabricated in one batch, achieving an average power conversion efficiency (PCE) of 19.00%. Finally, the whole fabrication process was conducted below 150 ℃, which is appropriate for a wide range of applications, such as flexible- and tandem- photovoltaic devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Gradient copper-doped nickel oxide was made as the HSL for Si PV. • The trade-off between interface recombination and built-in filed has been relaxed. • SOP strategy effective suppresses the Gd-NiO x /c-Si interface recombination. • A remarkable 20.3% efficiency was achieved for the proof-of-concept device. A prominent feature of photovoltaic devices is their ability to drive photo-generated charges to pathways of asymmetrical conductivity, guiding them to the corresponding electrodes. Under this guideline, the crystalline silicon (c-Si) solar cells dominate the photovoltaic (PV) market for decades and several optoelectronic losses and technological limitations are gradually emerging by now. To circumvent these issues, here, we replaced the doped-silicon emitter layer with a gradient copper-doped nickel oxide (Gd-NiO x), and incorporated a silicon oxide passivation (SOP) layer at the Gd-NiO x /c-Si interface, to construct the novel c-Si PV devices. Interestingly, it was observed that the Gd-NiO x hole selective layer can strengthen the built-in field by minimizing the front electrode/hole-selective layer barrier width and the SOP can reduce interface recombination simultaneously, thereby yielding a remarkable 20.3% efficiency for the proof-of-concept device. We believe the design proposed in this may be of interest for applications in PVs and other optoelectronic devices. [ABSTRACT FROM AUTHOR]

The fragile framework of the organic–inorganic metal halide perovskite has been strengthened for improving the stability of the PSCs by a multifunctional 2-amino-acetamidobenzotrifluoride (called BDP) with –NH 2 , C=O, and -CF 3 groups, simultaneously yielding a high efficiency of 21.62% for MAPbI 3 -based solar cells. [Display omitted] • A novel BDP-perovskite composite was developed for efficient and stable PSCs. • The BDP improved perovskite quality by retarding crystallization process. • The perovskite framework is reinforced by forming N-H...F bond with BDP. • The PCE of the BDP-treated device increased to 21.62% with a high V oc of 1.21 V. Perovskite solar cells (PSCs) are one of the most prospective photovoltaic devices because of their excellent photoelectric properties, yet their stability remains challenging. Apart from the reported passivation or encapsulation strategies, reinforcing the inherent framework of the perovskite is recognized as a substantial approach to stabilizing the PSCs. Herein, a multifunctional 2-amino-acetamidobenzotrifluoride (called BDP) with –NH 2 , C = O, and -CF 3 moieties is meticulously screened to strengthen the perovskite framework. The electron-donating groups of the BDP (–NH 2 and C = O) can simultaneously modify the crystallization process and achieve passivation, which devoted to reducing defect density; -CF 3 is used as a hydrophobic chemical stabilizer to form a moisture-resistant layer on the perovskite surface and suppress the MA+ ion migration by forming a hydrogen bond. Notably, the presence of the BDP also achieves a better energy level matching at the perovskite/hole transfer layer interface. Consequently, the power conversion efficiency (PCE) of MAPbI 3 solar cells is remarkably improved from 18.47% to 21.62%. Compared with the control devices, the PCE remains relatively stable under harsh external environmental conditions. Furthermore, the BDP also inhibits the lead leakage of PSCs, which is conducive to environmental applications. [ABSTRACT FROM AUTHOR]

A supramolecular bridging strategy with 2, 5-diaminobenzotrifluorid (DTF) molecular binder as the repeating unit was introduced to form a supramolecular-perovskite composite. The supramolecular binder plays a role of bridging the perovskite crystal grains, passivating the traps states of the perovskite films and producing excellent environmental stability. [Display omitted] • A supramolecular bridging strategy with DTF as repeat unit was proposed. • Bridging effect induced by the S-DTF for perovskite films was revealed. • Moisture-resistant MAPbI 3 solar cells with excellent performance was achieved. • Photovoltaic performance of MAPbI 3 solar cells have been effectively improved. The manipulation of grain boundaries in polycrystalline perovskites is an indispensable consideration for the photovoltaic performance and environmental stability of solar cells, because perovskite films obtained by solution process will inevitably introduce many defects in the grain boundaries. Although additives based on small molecules have proven to be effective defect passivators, their high volatility and diffusibility cannot satisfy the stability requirements of perovskite films. As an upgraded approach, herein, we introduced a supramolecular bridging strategy with 2,5-diaminobenzotrifluorid (DTF) molecular binder as the repeating unit to form a supramolecular-perovskite composite. The supramolecular binder plays a role of bridging the perovskite crystal grains, passivating the traps states of the perovskite films and producing excellent environmental stability, which is superior to the conventional additive engineering. As a result, the power conversion efficiency of the MAPbI 3 solar cell has been significantly increased from 18.8% to 21.0 %. The perovskite solar cells with S-DTF maintaining 93% of their original efficiency for over 30 days (∼70% humidity) in air ambient without encapsulation, exhibiting an excellent long-term stability. This will inspire a wider range of ideas beyond the regular additive engineering for improving the performance of polycrystalline perovskite-based photoelectronic devices. [ABSTRACT FROM AUTHOR]

Abstract: The defluoridation performance and adsorption mechanism of a high capacity hydrous zirconium oxide adsorbent were investigated. Fluoride adsorption on the hydrous zirconium follows a pseudo-second-order pattern. Maximum adsorption capacities of 124 and 68mg-F−/g-adsorbent were obtained in batch studies at pH 4 and 7, respectively. The adsorption capacity showed a continuously increasing trend with decreasing pH. The hydrous zirconium oxide is superior to most Zr-containing adsorbents. Surface titration and zeta potential measurements defined this adsorbent’s surface charging behavior and proved electrostatic interactions existed between fluoride and surface charge of the hydrous zirconium oxide. Raman, FTIR and 19F solid-state NMR observations definitively confirmed that fluoride was adsorbed by chemical reactions which formed Zr–F bonds on the hydrous zirconium oxide. XPS analyses indicated that a seven-coordinate polyhedral zirconium oxyfluoride species, ZrO2F5, and possibly some ZrO3F4 formed on the adsorbent’s surface by exchange reactions between surface hydroxyl groups with fluoride. Based on Zr-oxyfluoride species analyses by XPS, fluoride adsorption reactions on the hydrous zirconium oxide were suggested, including both associative and dissociative mechanistic pathways for fluoride uptake. This hydrous zirconium oxide adsorbent is a promising modestly priced adsorbent for practical application and its fluoride adsorption mechanisms are now better understood. [Copyright &y& Elsevier]