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The epitaxial growth of heterojunctions can reduce interface defects and enhance the stability of the crystal structures. However, a higher lattice mismatch can cause local lattice distortions at the interface, resulting in relaxed strains that eventually evolve into structural defects. Herein, a nearly zero-mismatch semicoherent interface was formed with a lattice mismatch (0.3%) by epitaxial growth CsPbBr3on CdS quantum dots (QDs), leading to a strain-free semicoherent interface. Results demonstrated that CdS/CsPbBr3heteronanocrystals (HNCs) had excellent stability and high photocatalytic performance compared with CsPbBr3. Theoretical calculations show that the Br–Cd bond forms strong electron coupling, which not only facilitates rapid electron transfer but also provides better structural stability. Compared to the individual CsPbBr3nanocrystals (NCs), the CdS/CsPbBr3HNCs exhibited higher stability and 2.1 times higher photocatalytic activity. It suggests that CdS/CsPbBr3HNCs have potential application value in energy and environmental fields.

The main process for industrial ammonia synthesis is the Haber–Bosch process, which is highly energy intensive with large amounts of CO2. The electrochemical ammonia synthesis is a potential alternative to the Haber–Bosch process because of its advantages of environmental friendliness; however, the inert N2molecule adsorption and activation are difficult and the competition of the hydrogen evolution reaction (HER) leads to a low Faraday efficiency (FE) and NH3yield of the nitrogen reduction reaction (NRR). The exploration of highly active and selective NRR catalysts that can efficiently adsorb and activate N2, as well as effectively inhibit the HER, is the key point of current research. In this study, NiFe–Nb2C catalysts were prepared by loading different Ni/Fe molar ratios of NiFe-LDH to Nb2C MXene and successfully introducing the synergistic effect between Ni and Fe. NiFe–Nb2C exhibited excellent NRR activity and the ammonia yield and FE hardly decreased in 4 consecutive cycle tests, and the current density remained stable in 24 h chronoamperometric tests, indicating that the NiFe–Nb2C catalyst has excellent electrochemical stability. DFT calculations indicate that the excellent NRR activity originated from the synergistic effect between NiFe-LDH and Nb2C MXene, which significantly promoted the activation of N2and the formation of *N2H.

Ammonia (NH3) is not only an essential feedstock for fertilizer, but also deemed as a potential hydrogen carrier. Worldwide industrial-scale NH3synthesis relies heavily on the Haber–Bosch process, which involves harsh operation under reaction conditions. In addition, nitrate is prevalent in groundwater and surface water, causing serious pollution. Electrocatalytic nitrate reduction reaction (NITRR), a sustainable ammonia synthesis technique, is the most promising alternative to the traditional Haber–Bosch process. We combined the noble metal Ru by impregnation based on Cu-based materials that can inhibit the HER to prepare Cu/Cu2O/RuO2@C composites. Surprisingly, the NH3yield of Cu/Cu2O/RuO2@C composites prepared by the NITRR reached 209.44 μmol cm−2h−1and 82.40% Faraday efficiency at −0.6 V (vs.RHE). Such a high reduction activity is attributed to the synergistic effect between Ru heteroatoms and the Cu-based material. In addition, Cu/Cu2O/RuO2@C exhibited good cycling stability and repeatability. This work highlights the potential importance of electrocatalyst design, contributing to research and exploration of related materials.

As a carbon-free energy source and carrier, NH3is an essential component used in agriculture, industry, and medicine. Currently, the main process for industrial ammonia production is the Haber–Bosch process, which is highly energy intensive with the emission of large amount of CO2. In contrast, electrochemical ammonia synthesis is a promising alternative for the Haber–Bosch process owing to its environmentally friendly nature, low energy consumption, and zero CO2emission. Meanwhile, as a widespread source of nitrogen in industrial wastewater and contaminated groundwater, nitrate has received extensive attention as the source for the synthesis of NH3. In this study, a Ru–Cu/Cu2O@Ti3C2catalyst was successfully prepared by combining highly conductive Ti3C2MXene with Ru–Cu/Cu2O@C. In 0.1 M KOH and KNO3electrolyte, the Ru–Cu/Cu2O@Ti3C2exhibited excellent nitrate reduction reaction (NO3RR) performance, achieving the highest faradaic efficiency of 48.3% at −0.7 V with a corresponding NH3yield of 128.35 μmol cm−2h−1. The excellent catalytic performance of Ru–Cu/Cu2O@Ti3C2was attributed to the synergistic interactions between multivalent Cu/Cu+, abundant metal active centers of Ru, and the excellent electrical conductivity of the two-dimensional Ti3C2MXene. This study may provide a practical pathway for converting nitrate wastewater to valuable ammonia products.

Developing transition metal sulfide electrocatalysts with high efficiency for hydrogen evolution reaction (HER) are highly expected to promote the development of hydrogen energy. Herein, novel iron tungsten sulfide heterojunction nanosheets (FexSy/WS2Ns) with a petal-like structure were prepared by a facile hydrothermal method. The prepared petal-like FexSy/WS2Ns owned a large diameter size of ∼1 μm and a thickness of 8 nm for each flake. The developed FexSy/WS2Ns exhibited excellent HER activity with an overpotential of 118 mV at 10 mA cm–2and a low Tafel slope of 87 mV dec–1in 0.5 M H2SO4, which is much better than that of single FexSyand WS2(>420 mV at 10 mA cm–2). This advanced HER activity is owed to the unique thin structure and more exposed active sites provided by defects between the crystal interface of FexSyand WS2. Furthermore, the FexSy/WS2Ns as a bifunctional electrocatalyst could achieve energy-saving water-splitting by replacing the oxygen evolution reaction with the urea oxidation reaction to decrease the applied voltage to 147 mV.

Single-function binders may not fulfill the diverse application requirements of Si, binder design strategy is reconginzed as an effective way to imrove the performance of Si-based anodes for lithium-ion batteries. In this study, a novel multifunctional polymer binder BDSA–DPA–PEGCE (BDP) incorporated by hard/soft interacting phases was designed. The hard domain of the BDP polymer binder is achieved through reversible covalent disulfide exchange, supramolecular noncovalent cooperative H-bonding, and π-π interactions, endowing self-healing ability and enhanced mechanical properties to maintain Si anodes integrity. The soft phase is dominated by the polyether segment, establishing efficient ion-hopping transportation pathways. Meanwhile, the pre-lithiation strategy is employed for compensating the consumption of Li resources. The volume expansion of the Si-based electrodes coordinated by the BDP binder is effectively suppressed, realizing improved cycling stability, high initial coulombic efficiency of 85.2%, and superior rate performance for Si-based half–cells and NCM523//Si/C full–cells. The BDP binder also promotes the formation of dense, stable and homogeneous SEI layer. This work offers valuable insights for developing multifunctional polymer binders to satisfy the specific demands of Si-based electrodes for rechargeable batteries.

Temporally intermittent and spatially dispersed renewable energy sources strongly call for large-scale energy storage devices. Aqueous aluminum-ion batteries show great potential for application due to their safety and low cost. Thus far, however, the ideal full-battery configuration is beyond the scope due to shortcomings with regards to suitable anode and cathode materials. Herein, we report a pioneering aqueous aluminum-ion battery system consisting of a Prussian white cathode, 1 M Al2(SO4)3aqueous electrolyte, and an organic 9,10-anthraquinone anode. The oxidation capability of the Prussian white cathode during the first charging allows for the fabrication of the full battery without pre-inserting aluminum ions, thus making the rocking-chair-type battery feasible. Importantly, the open-framework structure of the Prussian white and distinct enolization charge storage mechanism of 9,10-anthraquinone ensure fast reaction kinetics. The full battery exhibits cycling stability with a capacity retention of 89.1% over 100 cycles at 500 mA g–1, finishing a cycle in about 10 min. This work provides a pathway for developing rechargeable aqueous aluminum-ion batteries.

Abstract: Rechargeable batteries, which are used for renewable energy storage, have paved the way for reducing the enormous pressure of the energy crisis and environmental pollution. Recently, promising electrode materials with high energy and power density and favorable electrochemical performance for energy conversion and storage have been developed to meet the ever-growing demand for renewable power for electric vehicles or grid applications. MXenes, which constitute an impressive two-dimensional transition metal carbide/carbonitride family, exhibit great energy storage potential based on their ideal specific surface area, excellent electrical conductivity, and superior chemical durability in batteries. The recent advances in MXenes and their composites for metal-sulfur batteries (specifically lithium-sulfur and sodium-sulfur batteries) and metal-air batteries (specifically lithium-air and zinc-air batteries) are comprehensively and systematically summarized in this review. Furthermore, the performance management strategies, next-stage research prospects, and remaining practical challenges for MXene-based materials in battery applications are discussed in detail. This review may provide some guidance for the development and application of MXene-based electrode materials in renewable electrochemical energy storage. Graphic Abstract:

The electrochemical conversion of nitrogen (N2) to ammonia (NH3) under ambient conditions is a highly promising alternative to the energy-intensive Haber–Bosch process. However, it suffers from poor yields and selectivity because of the lack of efficient catalysts. Herein, we prepared an economical and eco-friendly efficient biochar catalyst from peanut shells and achieved a high ammonia yield (2.32 μmol h−1cm−2) and selectivity (faradaic efficiency of 26.97%) over 12 h of stable operation. The results of density functional theory calculations illustrate that association pathways are more likely to occur on the active sites Bio-N4, Bio-O37, and Bio-S58, while dissociation pathways always occurred on the active sites Bio-O15, Bio-O21, and Bio-O52. Furthermore, Bio-O21 is the most promising active site for the NRR following the NNH2dissociation pathway with a lower reaction barrier. The preferable adsorption of N2, desorption of NH3, and suppression of the HER demonstrated the peanut shell-derived material as a more promising catalyst for the NRR.

Lead halide perovskite has in recent years gained widespread interest due to its excellent physical and chemical properties, as well as superior optoelectronic performance. However, some restrictions still preclude full industrialization of the material, in particular toxicity issues and instability as a result to sensitivity to humidity. Lead-free all-inorganic double perovskite materials have thus recently become a focus of research. Herein, a new narrow bandgap lead-free double perovskite solar cell with a high-quality Cs2PtI6film is proposed. It exhibits an optical bandgap of 1.37 eV, absorption within a wide range of wavelengths, and a high absorption coefficient. Following optimization, the device displays a best power conversion efficiency of 0.72% with an open-circuit voltage of 0.73 V, a short-circuit current of 1.2 mA/cm2, and a fill factor of 0.82. Crucially, it also demonstrates excellent stability when exposed to extreme conditions such as high humidity, high temperature, and UV-light irradiation. Stability tests show that the PSCs can retain almost 80% of the original efficiency over 60 days stored in ambient temperature without any encapsulation, boosting prospects for applications of lead-free perovskite solar cells.

A major bottleneck hindering the performance and commercial application of cost-effective carbon-based perovskite solar cells (C-PSCs) is the contact issue at the interface of the perovskite layer and the carbon counter electrode. Herein, a new approach of intermediate-controlled interfacial engineering (IIE) utilizing an ultra-low-cost acetylene black material is developed for the first time that can improve the interfacial contact of C-PSCs. We achieved both high efficiency (16.41%) without hole-transport materials and good stability as a result of the optimal heterogeneous interfacial contact. Devices without any encapsulation consistently exhibit excellent environmental stability, retaining 93% of their original efficiency by storing in an ambient atmosphere (30 °C, 30% RH) for 2000 h and achieving 81% of their original efficiency by storing in a terrible air environment (85 °C, 65% RH) for 312 h. In addition, to acquire a deep understanding of carrier transport, a comparison of heterogeneous interfaces fabricated using different methods has been undertaken. In C-PSCs fabricated by the IIE method, the lower radioactive recombination and faster carrier transfer result in a shorter carrier lifetime. We present a promising future for the industrialization of C-PSCs by reducing the costs and improving the performance.

Research on tin–lead (SnPb) perovskite solar cells (PSCs) has gained popularity in recent years because of their low band gap, which could be applied to tandem solar cells. However, most of the work is based on inverted PSCs using PEDOT:PSS as the hole-transport layer as normal-structure PSCs show lower efficiency. In this work, the reason behind the low efficiency of normal-structure SnPb PSCs is elucidated and surface passivation has been tested as a method to overcome the problem. In the case of normal PSCs, at the interface between the titania layer and SnPb perovskite, there are many carrier traps observed originating from Ti–O–Sn bonds. In order to avoid the direct contact between titania and the SnPb perovskite layer, the titania surface is passivated with carboxylic acid C60resulting in an efficiency increase from 5.14 to 7.91%. This will provide a direction of enhancing the efficiency of the normal-structure SnPb PSCs through heterojunction engineering.

All-inorganic lead halide perovskite solar cells (PSCs) have drawn widespread interest because of its excellent thermal stability compared to its organic–inorganic hybrid counterpart. Poor phase stability caused by moisture, however, has thus far limited their commercial application. Herein, by modifying the interface between the hole-transport layer (HTL) and the perovskite light absorption layer, and by optimizing the HTL for better energy alignment, we controlled the growth of perovskite, reduced carrier recombination, facilitated carrier injection and transport, and improved the PSC’s power conversion efficiency (PCE) and moisture stability. When testing using a positive bias scan, we obtained a significant improvement in PCE, 9.49%, which is the champion efficiency of CsPbIBr2-based inverted PSC at present. The stability measurement shows that the passivated CsPbIBr2-based inverted PSCs can retain 86% of its initial efficiency after 1000 h preserved in ambient air with 65% relative humidity. This study paves a new way for enhancing the moisture stability and power conversion efficiency of CsPbIBr2-based PSCs.

In mixed halide perovskite, the halide phase segregation is commonly observed due to halide ion migration, which causes severe stability issues in perovskite devices. Here, we directly revealed the iodide-migration process via potentiostatic treatment in CsPbIBr2perovskite. The absence of iodide ions was reduced significantly via a Sb2S3interfacial modification. We further employed the density functional theory (DFT) calculation to optimize the geometry positions at the perovskite interface and radial distribution functions (RDF) to analyze the atom perturbation. The simulation yielded a slight distortion of the perovskite lattice at the Sb2S3–CsPbIBr2interface and iodide ion fluctuation was reduced due to the decrease of halide vacancies. In addition, the thermally stimulated current was calculated to evaluate the defect density in the modified perovskite device. Due to the Sb2S3interaction with perovskite, the device became stable against humidity and maintained its photoactivity over 400 h. The champion efficiency of 9.31% with 26.31% improvement was obtained in modified CsPbIBr2perovskite solar cells.

Layered perovskites have attracted considerable attention in optoelectronic applications because of their excellent electronic properties and stability. In this work, the quasi-2D Aurivillius halide perovskites are investigated using density functional theory. The single-layer Aurivillius perovskite Ba2PbI6is predicted to have a direct band gap of 1.89 eV, which is close to that of the Ruddlesden–Popper perovskite Cs2PbI4. The electronic structures near the Fermi level are mainly governed by the [PbX6] octahedra, which leads to electronic properties similar to that of Cs2PbI4. Decomposition energies reveal that these Aurivillius perovskites exhibit thermal instability. However, increasing the number of the [PbX6] octahedra layer can enhance the stability and reduce the band gap. Our results indicated that for n≥ 5, it is possible to synthesize the thermally stable Cl-based Aurivillius perovskite Ba2Csn-1PbnCl3n+3. Bi- and In-based Aurivillius perovskites are also calculated to evaluate the Pb-free alternatives. These calculations can serve as a theoretical support in exploring novel layered perovskites for optoelectronic applications.

In the present work, CuxCe1−xO2nanorod catalysts synthesized by a co-precipitation method were treated with nitric acid to remove all the surface copper species and merely preserve the matrix copper species in the framework of ceria. With the subsequent thermal treatment at various temperature, the re-dispersion phenomenon of the matrix copper was investigated to different degrees and showed a profound influence on the catalytic performance in CO-PROX. Various analysis methods (XRD Rietveld refinement, HRTEM, XPS, H2-TPR and in situDRIFTs) were used to characterize the texture/structure property, redox property and surface element distribution of the catalyst along with the re-dispersion process. The acid-treated process not only diminished the active copper species for CO adsorption but also destroyed the surface oxygen vacancy, which severely damaged the low-temperature CO oxidation activity of H–CuCe(rod). Motivated by the thermal treatment, the matrix copper species shifts from the framework to the surface region, and is dispersed as surface CuOxspecies. In cooperation with the recovered oxygen vacancy, the interfacial interaction between copper and ceria was rebuilt and the catalytic performance of H–CuCe(rod) was remarkably enhanced with higher CO conversion (T50%: 137 °C to 80 °C) and a broader temperature window (width: zero to 50 °C). With further elevating the calcination temperature, much more matrix copper species was re-dispersed as surface CuOxspecies and further stimulated the low-temperature CO oxidation activity of H–CuCe(rod)-600. However, the deficiency of the matrix copper interacting with the ceria lattice and the reduced oxygen vacancy concentration led to a rapid decrease in CO conversion at high temperature and narrowed the temperature window for H–CuCe(rod)-600 in the preferential oxidation of CO (CO-PROX). Our findings reveal that the CO-PROX performance of a shape-controlled copper–ceria catalyst is highly sensitive to the distribution of copper species and could be regulated by the acid and subsequent thermal treatment process, providing a new insight into the development of highly efficient copper–ceria catalysts for CO-PROX.

The solar‐driven interfacial evaporation system has attracted much attention in recent years due to its reduced heat loss and accelerated steam generation. As a low‐cost and readily available resource, wood is widely applied as photothermal materials in solar‐driven interfacial evaporation system because of its superior water transfer and heat loss prevention properties. Herein, a simple, mild, and cost‐effective method is employed to fabricate wood‐based photothermal materials. The results demonstrate that the solar absorption rate of wood‐nigrosine is more than 97.5% across a wide wavelength range (200–2500 nm), and an evaporation rate of 1.46 kg m−2h−1and evaporation efficiency (86.1%) are achieved under 1‐sun illumination (100 mW cm−2). The solar‐driven interfacial evaporation system based on wood‐nigrosine exhibits strong structural stability and processing capability for dyes and seawater. Deposition of nigrosine on wood surface by a simple spraying method is induced into wood‐based solar‐driven interfacial evaporation systems. This simple, mild, and cost‐effective water evaporation system obtains an evaporation rate of 1.46 kg m−2h−1and evaporation efficiency (86.1%).

All-inorganic perovskites are attracting increasing attention due to their superior thermal stability than that of the traditional CH3NH3PbI3, while their inferior phase stability in ambient conditions is still an unsolved issue. Here, for the first time, we report the incorporation of niobium (Nb5+) ions into the CsPbI2Br perovskite. Results indicate that Nb5+can effectively stabilize the photoactive α-CsPbI2Br phase by the possible substitution of Pb2+. With 0.5% Nb doping, the carbon electrode-based all-inorganic perovskite solar cells achieved a high photoconversion efficiency value of 10.42%, 15% higher than that of the control device. The Nb5+incorporation reduces the charge recombination in the perovskite, leading to a champion Vocvalue of 1.27 V and a negligible hysteresis effect. This work explicates the high compatibility of all-inorganic perovskite materials and unlocks the opportunities for the use of high-valence ions for perovskite property modification.

Although the efficiency of perovskite-based solar cell has boosted up to 23%, their stability hinders the further development due to the volatile nature of organic components in conventional organic-inorganic hybrid perovskites. All-inorganic perovskites have been reported to achieve enhanced thermal stability. Herein we applied xanthate in all-inorganic perovskite to realize the sulfur-doped CsPbIBr2for superior phase stability. The additive cesium xanthate (CsXth) could be decomposed into cesium sulfides during annealing process. The divalent S2-lies in the interstices of perovskite lattice and strongly coordinates with CsPbIBr2to stabilize the ɑ-phase, as a result, greatly enhanced stability was achieved at ambient air with 65% relative humidity (RH) compared with the reference film. Moreover, we obtained a champion efficiency of 9.78% with a high open-circuit voltage (Voc) of 1.30 V based on 5% CsXth-CsPbIBr2under humid air. Performance of sulfur-doped perovskite device shows almost no decay in 10 h under humid air with 65% RH without encapsulation. These advantages provide an efficient way to prepare more efficient and superior stable perovskite device, which is beneficial toward commercialization in the future.

Unavoidable defects in grain boundaries (GBs) are detrimental and critically influence the organometal halide perovskite performance and stability. To address this issue, semiconducting molecules have been employed to passivate traps along perovskite GBs. Here, we designed and synthesized three squaraine molecules (SQ) with zwitterionic structure to interact with under-coordinated Pb2+and passivate Pb–I antisite defects. Density functional theory calculation shows symmetric O atoms could coordinate with perovskite grains simultaneously, resulting in continuous charge distribution at the SQ–perovskite interface. The energetic traps distribution in CH3NH3PbI3perovskite is influenced significantly by the interaction between SQ and perovskite as analyzed by thermally stimulated current, in which the deep-level defects are considerably reduced due to efficient SQ passivation. In addition, we explore how SQ molecules with different energy offset affect the charge extraction, which is suggested to facilitate exciton separation at the perovskite–SQ interface. These benefits lead to enhanced perovskite efficiency from 15.77 to 18.83% with the fill factor approaching 80%, which is among the highest efficiency reported for MAPbI3solar cells fabricated in an ambient environment at 60% relative humidity (RH). Considerable retardation of perovskite device degradation was achieved, retaining 90% of initial efficiency when kept 600 h at 60 ± 5% RH.

During the last years, lead perovskites have achieved high power conversion efficiency of 23%. However, their long-term stability and toxicity are still crucial issues that required attention. In this study, we are the first to report on the synthesis and characterizations of a new lead-free mixed halide-chalcogenide perovskite MABiI2S (MBIS), and have determined its physical and optical properties by various testing methods. The MBIS has a low bandgap of 1.52 eV, with an extended absorption onset up to over 1000 nm. Solar cells fabricated with the MBIS were inspected and device improvements were applied.Discovering new lead-free perovskite has always been a chanllenge. In this letter we reported the synthesis and characterization of the new mixed sulfur-iodine lead-free perovskite MABiI2S who displayed narrow bandgap. The solar cells based on this material were fabricated, and enhancement methods for device performance improvment were applied.

For the first time, WO2.72nanowires were in-situ grown on carbon cloth by a simple solvothermal reaction. The nanowire WO2.72/carbon cloth (NW WO2.72/CC) electrode showed good electrochemical performance with specific capacitance (Cs) reaching up to 398 F g−1at a current density of 2 A g−1. The capacitance of 240 F g−1was retained at a high current density of 16 A g−1. To further evaluate the energy storage performance, flexible asymmetric supercapacitors (FASCs) were fabricated using the activated carbon/carbon cloth (AC/CC) as negative electrode and NW WO2.72/CC as positive electrode, respectively. The FASCs delivered a high energy density of 28 Wh kg−1at a power density of 745 W kg−1and 13 Wh kg−1even at a high power density of 22.5 kW kg−1. More impressively, 81% of the specific capacitance of the FASCs was retained after 10,000 cycles, indicating excellent cycle stability. This work indicates the NW WO2.72/CC holds a great potential for application in energy storage devices.

Besides the high-quality perovskite light absorbing layer, the electron and hole transport layers also play significant roles in achieving high-efficiency planar perovskite solar cells (PVSCs). In this study, a facile, environmentally friendly, one-step spinning coating method is employed to fabricate high-quality indium zinc oxide (IZO) electron transport layer (ETL). Improvements in charge transport, conductivity, and light transmittance of IZO ETL relative to that of TiO2-ETL should be responsible for the large short circuit current density of PVSCs. Using this optimized IZO ETL film, a high-power conversion efficiency (PCE) of 16.25% was achieved, which resulted in an absolute efficiency gain of 2.42% compared with TiO2-based PVSC (13.83%). A steady-state efficiency of 15.8% with negligible hysteresis was also demonstrated.

Lead halide perovskite has emerged as a promising photovoltaic material due to its excellent power conversion efficiency (PCE). However, the toxicity problem of lead-based perovskite hampers the commercialization of perovskite solar cells. Here, we develop several Sb(V) complexes with pyridyl cations and serve as absorber layer for lead-free perovskite solar cells. The designed complexes were based on 4-tert-butylpyridine (tBP) and N-ethylpyridinium (N-EtPy) cations with bandgaps of 2.01 eV and 1.95 eV, which showed their potential for solar cells and optoelectronic applications. We also found a chemical rule for stable Sb complexes in terms of the bond connectivity of pnictogen-antimony. Initial studies produce a solar cell with a PCE of 0.9% and offer inspiration for further exploration of environment-friendly perovskite families.Sb(V) complexes with pyridyl cations were synthesized and served as absorber layer for lead-free perovskite solar cells. The Sb-based solar cell produced a PCE of 0.9% and offered inspiration for further exploration of environment-friendly perovskite families.

TiO2is commonly used as an electron-transporting material in perovskite photovoltaic devices due to its advantages, including suitable band gap, good photoelectrochemical stability, and simple preparation process. However, there are many oxygen vacancies or defects on the surface of TiO2and thus this affects the stability of TiO2-based perovskite solar cells under UV light. In this work, a thin (monolayer) SbI3modification layer is introduced on the mesoporous TiO2surface and the effect at the interface between of TiO2and perovskite is monitored by using a quartz crystal microbalance system. We demonstrate that the SbI3-modified TiO2electrodes exhibit superior electronic properties by reducing electronic trap states, enabling faster electron transport. This approach results in higher performances compared with electrodes without the SbI3passivation layer. CH3NH3PbI3perovskite solar cells with a maximum power conversion efficiency of 17.33% in air, accompanied by a reduction in hysteresis and enhancement of the device stability, are reported.

Despite the high efficiency of MAPbI3perovskite solar cells, the long term stability and degradation in humid atmosphere are issues that still needed to be addressed. In this work, magnesium iodide (MgI2) was first successfully used as a dopant into MAPbI3perovskite prepared in humid air atmosphere. Mg doping decreased the valence band level, which was determined from photoelectron yield spectroscopy. Compared to the pristine MAPbI3perovskite film, the 1.0% Mg-doped perovskite film showed increased crystal grain size and formation of pinhole-free perovskite film. Performance of the solar cell was increased from 14.2% of the doping-free solar cell to 17.8% of 1.0% Mg-doped device. Moreover, 90% of the original power conversion efficiency was still retained after storage in 30–40% relative humidity for 600 h.

High-efficiency perovskite solar cells (PSCs) need to be fabricated in the nitrogen-filled glovebox by the atmosphere-controlled crystallization process. However, the use of the glovebox process is of great concern for mass level production of PSCs. In this work, notable efficient CH3NH3PbI3solar cells can be obtained in high humidity ambient atmosphere (60–70% relative humidity) by using acetate as the antisolvent, in which dependence of methyl, ethyl, propyl, and butyl acetate on the crystal growth mechanism is discussed. It is explored that acetate screens the sensitive perovskite intermediate phases from water molecules during perovskite film formation and annealing. It is revealed that relatively high vapor pressure and high water solubility of methyl acetate (MA) leads to the formation of highly dense and pinhole free perovskite films guiding to the best power conversion efficiency (PCE) of 16.3% with a reduced hysteresis. The devices prepared using MA showed remarkable shelf life stability of more than 80% for 360 h in ambient air condition, when compared to the devices fabricated using other antisolvents with low vapor pressure and low water solubility. Moreover, the PCE was still kept at 15.6% even though 2 vol % deionized water was added in the MA for preparing the perovskite layer.