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The introduction of Zn2+ and Mn2+ to (Bmpip)2[PbBr4] effectively alters the polyhedral configuration from a PbBr42− tetrahedron to a Pb3Br115− trimer. As a result, the self-trapped exciton emission properties are significantly enhanced.

High-efficiency perovskite solar cells (PSCs) normally rely on costly, high purity (>99.99%), air-sensitive raw materials that vary batch-to-batch. The perovskite films and devices derived from conventional raw materials mixture method suffer from inferior reproducibility of optoelectronic properties and performance, as well as discounted promise towards low-cost scalable manufacturing. Distinguished from the direct mixing of raw materials, the preparation of perovskite films with precursors made by the redissolution of perovskite crystals holds the promise to make PSCs more affordable, reproducible, efficient and stable. The resultant perovskite films inherit the exceptional characteristics of the parent perovskite crystals, such as high crystallinity, high purity, accurate stoichiometric ratio, and low trap-state density, as well as good ambient and phase stability. Herein, we summarize recent progress on the employment of the perovskite crystals redissolution strategy for achieving low-cost, efficient perovskite-based solar-to-electricity conversion, which will help both popularize the redissolution strategy and reveal unprecedented advantages gained by its adoption.

Zero-dimensional metal halide perovskites have captured intense research interest owing to their unique optoelectronic properties. Particularly, metal halides with the ns2 electronic configuration are of great interest owing to the high-temperature sensitivity of their photoluminescence, which could be applied to remote optical thermometry (ROT). Herein, all-inorganic and lead-free halide perovskite Te4+-doped Cs2InCl5·H2O single crystals (SCs) were prepared through the hydrothermal method and showed a strong temperature dependence of photoluminescence lifetime. Upon Te4+ doping, the nonemissive Cs2InCl5·H2O SC exhibits a bright orange emission at 660 nm with a wide full width at half maximum of 180 nm. The strong phonon-exciton coupling promotes the formation of self-trapped excitons in the soft lattice of the zero-dimensional Te4+-doped Cs2InCl5·H2O SC. The Te4+ ions with the 5s2 electronic configuration endow the Te4+-doped Cs2InCl5·H2O SC with a strong temperature-dependent photoluminescence lifetime. This SC reaches a maximum specific sensitivity of 0.062K−1 at 320 K, thereby showing the potential advantages of indium-based metal halide perovskites in ROT applications.

Simplified structures of perovskite solar cells can reduce the fabrication and materials cost while simultaneously achieving high efficiencies, which are highly attractive for practical industrial production.

The optoelectronic performance of CsPbBr3 nanocrystal (NC) has been dramatically limited by the severe charge carrier recombination and its narrow light absorption range, which are anticipated to be resolved via coupling with plasmonic Au nanoparticle (NP). In view of this, CsPbBr3–Au nanocomposite is fabricated and further employed as a concept model to study the electronic interaction between perovskite NC and Au NP for the first time. It has been found that the excitation-wavelength dependent carrier transfer behavior exists in CsPbBr3–Au nanocomposite. Upon illumination with visible light (λ >420 nm), photo-generated electrons in CsPbBr3 can inject into Au with an electron injection rate and efficiency of 2.84 × 109 s−1 and 78%, respectively. The boosted charge separation is further translated into a 3.2-fold enhancement in CO2 photocatalytic reduction activity compared with pristine CsPbBr3. On the other hand, when solely exciting Au NP with longer wavelength light (λ >580 nm), the localized surface plasmon resonance (LSPR) induced hot electrons in Au NPs can transfer to CsPbBr3 NC and further participate in photocatalytic reaction towards CO2 reduction. The present study provides new insights into preparing plasmonic nanostructure to enhance the performance of perovskite based optoelectronic devices.

Color tunability of perovskite light-emitting diodes (PeLEDs) by mixed halide compositional engineering is one of the primary intriguing characteristics of PeLEDs. However, mixed halide PeLEDs are often susceptible to color red-shifting caused by halide ion segregation. In this work, strongly quantum-confined perovskite nanowires (QPNWs) made of CsPbBr

The performances of electron-transport-layer (ETL)-free perovskite solar cells (PSCs) are still inferior to ETL-containing devices. This is mainly due to severe interfacial charge recombination occurring at the transparent conducting oxide (TCO)/perovskite interface, where the photo-injected electrons in the TCO can travel back to recombine with holes in the perovskite layer. Herein, we demonstrate for the first time that a non-annealed, insulating, amorphous metal oxyhydroxide, atomic-scale thin interlayer (ca. 3 nm) between the TCO and perovskite facilitates electron tunneling and suppresses the interfacial charge recombination. This largely reduced the interfacial charge recombination loss and achieved a record efficiency of 21.1 % forn-i-pstructured ETL-free PSCs, outperforming their ETL-containing metal oxide counterparts (18.7 %), as well as narrowing the efficiency gap with high-efficiency PSCs employing highly crystalline TiO(2)ETLs.

Summary A luminescent all-inorganic manganese-bismuth heterometallic Cs4MnBi2Cl12 perovskite single crystal has been synthesized with a [BiCl6]3−-[MnCl6]4−-[BiCl6]3− triple-layered two-dimensional structure. Benefit from the effective energy transfer from [BiCl6]3− octahedron donor to luminescent [MnCl6]4− acceptor, Cs4MnBi2Cl12 shows a photoluminescence quantum yield (PLQY) of up to 25.7% (~610 nm), 51-fold higher than the Bi unalloyed CsMnCl3·2H2O counterpart. Suggested by the theoretical calculations, Bi and Mn exhibit hybridization in conduction and valence band, which further results in a favorable low activation energy for exciton transfer (~23 meV). By virtue of all-inorganic chemical composition, Cs4MnBi2Cl12 exhibits impressive stability toward moisture, light, and heat. Furthermore, Cs4MnBi2Cl12 features strong soft X-ray attenuation and bright radiative luminescence under X-ray excitation, which pave a way for its application in medical flat-panel X-ray digital radiography. This work presents a new avenue toward fabrication of function-directed material with tailored photoelectric properties.

Ligand-assisted reprecipitation strategy (LARS) is one of the most popular methods for the fabrication of lead halide perovskite nanocrystals; however, it has always been criticized for poor repeat...

Summary Lead halide perovskite (PVK) has been deemed as a promising photocatalyst alternative because of its remarkable photoelectrical properties; however, the severe charge recombination has limited its catalytic activity. Herein, we report a PVK-based Z-scheme heterojunction, α-Fe2O3/Amine-RGO/CsPbBr3, for high-efficiency CO2 reduction in the presence of H2O. By delicately controlling the interfacial interaction, effective Z-scheme electron transfer from α-Fe2O3 to CsPbBr3 is built, leading to boosted charge separation and prolonged carrier lifetime, as confirmed by electron spin resonance (ESR), transient absorption (TA) spectra, etc. The impactful spatial separation of photo-generated carriers in Z-scheme system finally enables an 8.3-fold enhancement in photocatalytic performance as compared to CsPbBr3. A stable product yield of 469.16 μmol g−1 and an electron consumption yield of 3,132.46 μmol g−1 are achieved. This work is expected to provide deep insights into boosting the photocatalytic performance of PVK by modulating the charge carrier dynamics.

Organic small molecules like ammonium halide salts (AHSs) are widely used to suppress the non-radiative charge recombination of solution-processed halide perovskite films with defective surface and unfavorable energy levels for enhanced photovoltage, but more often than not at a cost of enlarging the band gap of perovskite materials, which limits the light absorption and thus, the photocurrent density. In addition, there is still a lack of fundamental understanding and visual characterization of the surface and bulk composition change upon subsequent surface treatment with heterogeneous ingredients. Herein, we report and identify that AHS soaking treatment enables the formation of δ-FAPbI3 on the surface of the perovskite film for defect passivation functions, thus reducing the interfacial recombination loss and increasing photovoltage. Meanwhile, the AHS molecules diffuse and alloy with the bulk perovskite material to reduce the band gap, red-shifting the absorption region and thus increasing the photocurrent. Blade-coated perovskite solar cells (PSCs) prepared via AHS treatment achieved a champion power conversion efficiency (PCE) of 21.9% with a high open-circuit voltage (Voc) up to 1.18 V under AM 1.5G sun illumination, which is remarkably higher than the pristine PSCs without any treatment (19.2%), and outperforms other blade-coated PSCs, regardless of their perovskite compositions. Surface treatment of perovskite films with functional, organic small molecules is a promising strategy for rational composition management and favorable gradient distribution, which are beneficial for realizing efficient and stable PSCs.

In order to solve the problem of bridgehead jumping caused by uneven settlement of soft soil subgrade, this paper proposes a non-excavation treatment scheme of inclined jet grouting pile reinforcement based on the demonstration project of eightword section of Xiaojiang Interchange Bridge in G15 Shenhai Expressway, the settlement amount of the eight-character bridge demonstration project and the reinforcement effect of using inclined rotary jet grouting pile to strengthen soft soil subgrade are analyzed and studied based on the FLAC3D three-dimensional numerical simulation. The results show that: The primary settlement is mainly concentrated in the period from 2000 to 2019,and the main consolidation settlement is dominant, the secondary consolidation settlement in the later period has a trend of gradual regional stability; The composite foundation composed of inclined jet grouting pile and silt soil can effectively enhance the anti-deformation ability of the soil under the embankment, and the settlement of the treated area is effectively controlled; The direction of the inclined jet grouting pile along the road length gradually decreases, and the road surface settlement also presents a gentle gradual effect through the zoning and gradual treatment of the soft soil subgrade in the jump-off section at the bridge head. The research results can provide a design basis for the treatment of soft soil subgrade in the demonstration section and have certain theoretical and practical significance.

Low-dimensional lead halide perovskite materials recently have drawn much attention owing to the intriguing broadband emissions; however, the toxicity of lead will hinder their future development. Now, a lead-free (C4 H14 N2 )2 In2 Br10 single crystal with a unique zero-dimensional (0D) structure constituted by [InBr6 ]3- octahedral and [InBr4 ]- tetrahedral units is described. The single crystal exhibits broadband photoluminescence (PL) that spans almost the whole visible spectrum with a lifetime of 3.2 μs. Computational and experimental studies unveil that an excited-state structural distortion in [InBr6 ]3- octahedral units enables the formation of intrinsic self-trapped excitons (STEs) and thus contributing the broad emission. Furthermore, femtosecond transient absorption (fs-TA) measurement reveals that the ultrafast STEs formation together with an efficient intersystem crossing has made a significant contribution to the long-lived and broad STE-based emission behavior.

Although great advancements have been successfully achieved in ligand-assisted reprecipitation strategy (LARP) towards lead halide perovskite nanocrystals (NCs) synthesis, it still remains challenging to develop bright and stable iodide-based perovskite NC via facile LARP. Herein, strikingly bright MAPbI3 NCs with photoluminescence quantum yield (PLQY) as high as 79% are synthesized via replacing the raw material (MAI and PbI2) with MAPbI3 crystal powder during LARP procedure. It has been found that crystal powder derived MAPbI3 NCs are more iodide-rich compared with that based on raw material, which is favorable to passivate the surface trap state. Accordingly, femtosecond transient absorption spectroscopies and space charge limited current measurements have corroborated that the trap density is much less in crystal powder resulted MAPbI3 NCs. Further analyses indicate stronger solvation with reduced precursor colloid size has been observed in crystal powder derived precursor solution probably due to the formation of MAPbI3·DMF. This work has provided a facile but valid method to enhance the photoluminescence of perovskite NC via modulating the beginning precursor solution.

Heterojunction engineering has played an indispensable role in the exploitation of innovative artificial materials with exceptional properties and has consequently triggered a new revolution in achieving high-performance optoelectronic devices. Herein, an intriguing halide perovskite (PVK) and metal dichalcogenide (MD) heterojunction, i.e., a lead-free Cs2SnI6 perovskite nanocrystal/SnS2 nanosheet hybrid, was fabricated in situ for the first time. Comprehensive investigations with experimental characterizations and theoretical calculations demonstrate that cosharing of the Sn atom enables intimate contact in the Cs2SnI6/SnS2 hybrid together with a type II band alignment structure. Additionally, ultrafast carrier separation between SnS2 and Cs2SnI6 has been observed in the Cs2SnI6/SnS2 hybrid by transient absorption measurements, which efficiently prolongs the lifetime of the photogenerated electrons in SnS2 (from 1290 to 3080 ps). The resultant spatial charge separation in the Cs2SnI6/SnS2 hybrid evidenced by Kelvin probe force microscopy (KPFM) significantly boosts the photocatalytic activity toward CO2 reduction and the photoelectrochemical performance, with 5.4-fold and 10.6-fold enhancements compared with unadorned SnS2. This work provides a facile and effective method for the in situ preparation of PVK-MD heterojunctions, which may significantly stimulate the synthesis of various perovskite-based hybrid materials and their further optoelectronic applications.

Recent years have witnessed an explosive interest in branched TiO2 nanostructures (BTNs) due to their promising applications in a wide range of energy-related fields. As anode materials for solar cells (dye- or quantum dot-sensitized solar cells and perovskite solar cells), photoelectrochemical synthetic cells and energy storage devices (e.g., Li-ion batteries), BTNs with inherent nature of structural hierarchy and porosity, provide fascinating optical, electrical and electrochemical properties such as high surface area, superior light scattering and confinement, and fast electron transport. This review summarizes the recent advances in the preparation of BTNs with tailored host-guest morphologies, branches compositions and structural complexity. Their promising progress achieved in the field of energy conversion and storage is discussed. Two blossoming representatives, including the tree-like branched TiO2 nanoarrays and urchin-like branched TiO2 spheres, are highlighted to shed light on the effect of smart surface branched modification on improving the solar-to-electricity or solar-to-fuel conversion efficiencies, and increasing energy (power) densities. In addition, we also provide perspective on the new trend and future directions of novel multifunctional BTNs for next-generation energy conversion and storage devices.

Low-dimensional luminescent lead halide perovskites have attracted tremendous attention for their fascinating optoelectronic properties, while the toxicity of lead is still considered a drawback. Herein, we report a novel lead-free zero-dimensional (0D) indium-based perovskite (Cs2 InBr5 ⋅H2 O) single crystal that is red-luminescent with a high photoluminescence quantum yield (PLQY) of 33 %. Experimental and computational studies reveal that the strong PL emission might originate from self-trapping excitons (STEs) that result from an excited-state structural deformation. More importantly, the in situ transformation between hydrated Cs2 InBr5 ⋅H2 O and the dehydrated form is accompanied with a switchable dual emission, which enables it to act as a PL water-sensor in humidity detection or the detection of traces of water in organic solvents.

Suppressed charge recombination and facilitated charge collection are critical for achieving perovskite solar cells (PSCs) with improved efficiency and stability. Herein, a multifunctional 2D polymeric semiconductor is incorporated into perovskite ink to assist the crystal growth of perovskite films with large grains and fewer defects. Anchoring heterogeneous polymeric molecules on perovskite not only enhances the efficacy of defect passivation at the grain boundaries and/or surface but also facilitates the charge extraction and collection, as evidenced by thermal admittance spectroscopy and femtosecond transient absorption spectroscopy. Accordingly, the PSCs incorporated with a polymeric semiconductor achieve power conversion efficiencies (PCEs) up to 21.1% (aperture 0.16 cm2) and 19.5% (aperture 1.0 cm2), featuring an illustrious open-circuit voltage of 1.16 V (corresponding to a small voltage loss of 0.39 V) and an improved device operational stability (∼90% initial efficiency retained after constant one sun illumination for 500 h). This work highlights the effectiveness of using multifunctional passivation agents capable of providing surprisingly robust efficacy in defect passivation of perovskite, which are also advantageous to crystal growth modulation and carrier dynamic management for efficient and stable PSCs.

Solar-driven CO2 conversion for chemical fuel production has been regarded as an effective strategy to alleviate environmental and energy issues. In this study, we constructed a novel composite catalyst film, in which CsPbBr3 nanocrystals (NCs) were loaded on a hierarchical branched ZnO nanowire (BZNW)/macroporous graphene scaffold (CsPbBr3 NC/BZNW/MRGO). This well-designed multi-dimensional architecture rationally integrated the excellent visible-light absorption capability of CsPbBr3 NCs, and fast charge transport and improved CO2 capture ability afforded by ZnO nanowire-branched macroporous graphene. Due to this favorable synergistic effect, a boosted photocatalytic performance was achieved with a photoelectron consumption rate of 52.02 μmol gcat−1 h−1 under visible light irradiation, which is 4.98 and 1.65 times higher than that of CsPbBr3 NC (10.44 μmol gcat−1 h−1) and CsPbBr3 NC/MRGO (31.52 μmol gcat−1 h−1), respectively. Furthermore, desirable CH4 selectivity of up to 96.7% was achieved.

The development of an all-inorganic lead-free perovskite nanocrystal is of crucial importance to solve the instability and lead toxicity of organic–inorganic lead hybrid perovskites. Herein, single-layered Cs4CuSb2Cl12 nanocrystals (NCs) with a narrow band gap of 1.6 eV were prepared for the first time via an ultrasonic exfoliation technique. This powerful top-down method was further generalized to synthesize a class of lead-free perovskite (Cs3Bi2X9 and Cs3Sb2X9) NCs. The experimental and theoretical studies revealed that not only inter-layer van der Waals forces but also in-plane chemical bonds played a critical role in the exfoliation process. Specifically, smaller uniform-sized NCs were observed for Cs4CuSb2Cl12 (∼3 nm) as compared to those for Cs3Sb2Cl9 (∼20 nm) although both Cs4CuSb2Cl12 and Cs3Sb2Cl9 exhibited a similar exfoliation energy (∼0.310 J m−2). This can be ascribed to the weaker in-plane chemical bonds of Cu–Cl (2.808 A) and Sb–Cl (2.924 A) in Cs4CuSb2Cl12 than the uniform Cl–Sb bond (2.69 A) in Cs3Sb2Cl9 that allow for an easier exfoliation process. In addition, exfoliation of the Cs4CuSb2Cl12 microcrystal into NCs results in an indirect-to-direct bandgap transition and a reduced electron effective mass, which provides a rapid and steady photoelectrochemical response, demonstrating that Cs4CuSb2Cl12 NCs are a promising candidate for optoelectronic applications.

Halide perovskite single crystals (SCs) have recently been regarded as a promising candidate in optoelectronic devices by virtue of their remarkable intrinsic properties. Herein, a laminar MAPbBr3/MAPbBr3−xIx (MA = CH3NH3+) graded heterojunction single crystal (GHSC) with a thickness of about 11 μm and an area of 4 × 5 mm has been synthesized via a space-limited inverse temperature crystallization growth method and a gaseous halide exchange process in sequence. Compared to the pristine MAPbBr3 SC, such a MAPbBr3/MAPbBr3−xIx GHSC possesses graded valence band alignment via a halide gradient distribution, which significantly enhances the hole extraction and accelerates carrier transport, leading to a high-performance perovskite SC photodetector with an improved external quantum efficiency of ≈170% at −2 V and an impressively rapid response speed of 0.56 μs. Our results provide a promising strategy to solve the carrier extraction obstacle and suppress recombination loss, which opens potential optoelectronic applications of laminar heterojunction SCs.

The past few years have witnessed an impressive development of all-inorganic halide perovskite nanocrystals. In this report, a series of CsPbBrxI3−x nanocrystal/carbon nanotube (CsPbBrxI3−x NC/CNT, x = 3, 2, 1.5, 1) hybrid photoelectrodes have been fabricated and further employed in photoelectrochemical cells. Benefiting from the high conductivity of CNTs, the hybrid samples show accelerated charge separation and transfer actions after photoexcitation. Moreover, increasing the I/Br ratio in CsPbBrxI3−x nanocrystals accounts for a wider adsorption range but inferior phase stability, which calls for a delicate balance. As a result, the highest photocurrent density of 420 μA cm−2 is finally achieved by CsPbBr1.5I1.5 NC/CNT (200), which corresponds to a 7.7-fold improvement over the prototype CsPbBr3. This report offers an in-depth understanding of the charge transfer behavior along with photoelectrochemical performance of CsPbBrxI3−x nanocrystal/CNT, which can surely stimulate metal halide perovskite nanocrystal-based hybrid materials for promising optoelectronic, photocatalysis and photoelectrochemical applications.

Exploring efficient photocatalysts for water oxidation is highly demanded because of their significant role in artificial photosynthesis. The research of metal-organic frameworks (MOFs) based photoelectrochemical (PEC) water splitting is promising but still in its infancy due to the challenge to fabricate high-quality MOFs photoelectrode. Here an Fe2O3/Fe-based MOF core/shell nanorod is prepared for efficient PEC water oxidation via a facile surfactant-assisted solvothermal method. With polyvinylpyrrolidone (PVP) molecules as intermedia, an ultrathin MOF shell of several nanometers thick can be controllably grown on the surface of Fe2O3 nanorod. Charge dynamical behaviors study by ultrafast transient absorption spectroscopy (TAS) and photoelectrochemical impedance spectroscopy (PEIS), reveal that the ultrathin MOF shell is crucial to promote the charge separation by providing a cascade band level, but also accelerate the hole injection efficiency via exposing more accessible Fe-oxo cluster active sites. Accompanied with good visible-light response, the Ti-doped Fe2O3/NH2-MIL-101(Fe) photoanode delivers a boosted photocurrent density of 2.27 mA cm−2 at 1.23 V vs. RHE, which is about 2.3 folds of that of pristine Fe2O3. This study provides new insights into the rational design of semiconductor/MOFs hybrid materials for photo/photoelectrochemical catalysis.

Halide perovskite single-crystals have recently been widely highlighted to possess high light harvesting capability and superior charge transport behaviour, which further enable their attractive performance in photovoltaics. However, their application in photoelectrochemical cells has not yet been reported. Here, a methylammonium lead bromide MAPbBr3 single-crystal thin film is reported as a photoanode with potential application in photoelectrochemical organic synthesis, 2,5-dimethoxy-2,5-dihydrofuran. Depositing an ultrathin Al2O3 layer is found to effectively passivate perovskite surface defects. Thus, the nearly 5-fold increase in photoelectrochemical performance with the saturated current being increased from 1.2 to 5.5 mA cm−2 is mainly attributed to suppressed trap-assisted recombination for MAPbBr3 single-crystal thin film/Al2O3. In addition, Ti3+-species-rich titanium deposition has been introduced not only as a protective film but also as a catalytic layer to further advance performance and stability. As an encouraging result, the photoelectrochemical performance and stability of MAPbBr3 single-crystal thin film/Al2O3/Ti-based photoanode have been significantly improved for 6 h continuous dimethoxydihydrofuran evolution test with a high Faraday efficiency of 93%., Perovskite single-crystal thin films inherit the advantages of low trap-states, well-defined thickness and remarkable stability. Now, researchers successfully employed MAPbBr3 single-crystal thin film as photoanode in the photoelectrochemical production of organic 2,5-dimethoxy-2,5-dihydrofuran.

Indium-antimony bimetallic halide single crystal exhibits single-source white-light emission and anti-counterfeiting potential., Although single-source white emissive perovskite has emerged as a class of encouraging light-emitting material, the synthesis of lead-free halide perovskite materials with high luminous efficiency is still challenging. Here, we report a series of zero-dimensional indium-antimony (In/Sb) alloyed halide single crystals, BAPPIn2–2xSb2xCl10 (BAPP = C10H28N4, x = 0 to 1), with tunable emission. In BAPPIn1.996Sb0.004Cl10, bright yellow emission with near 100% photoluminescence quantum yield (PLQY) is yielded when it was excited at 320 nm, which turns into bright white-light emission with a PLQY of 44.0% when excited at 365 nm. Combined spectroscopy and theoretical studies reveal that the BAPP4+-associated blue emission and inorganic polyhedron–afforded orange emission function as a perfect pair of complementary colors affording white light in BAPPIn1.996Sb0.004Cl10. Moreover, the interesting afterglow behavior, together with excitation-dependent emission property, makes BAPPIn2–2xSb2xCl10 as high-performance anti-counterfeiting/information storage materials.

Akin to single-site homogeneous catalysis, a long sought-after goal is to achieve reaction site precision in heterogeneous catalysis for chemical control over patterns of activity, selectivity and stability. Herein, we report on metal phosphides as a class of material capable of realizing these attributes and unlock their potential in solar-driven CO2 hydrogenation. Selected as an archetype, Ni12P5 affords a structure based upon highly dispersed nickel nanoclusters integrated into a phosphorus lattice that harvest light intensely across the entire solar spectral range. Motivated by its panchromatic absorption and unique linearly bonded nickel-carbonyl-dominated reaction route, Ni12P5 is found to be a photothermal catalyst for the reverse water gas shift reaction, offering a CO production rate of 960 ± 12 mmol gcat−1 h−1, near 100% selectivity and long-term stability. Successful extension of this idea to Co2P analogs implies that metal phosphide materials are poised as a universal platform for high-rate and highly selective photothermal CO2 catalysis., There exists an urgent need to develop new materials to convert CO2 to useful products. Here, authors demonstrate metal phosphide nanoparticles to enable light-driven CO2 hydrogenation with high activities and near-unity selectivity.

Though coating CsPbBr3 nanocrystal (NC) with an outer layer has been regarded as an effective strategy to address its instability issues, deep investigations into the electronic interaction between CsPbBr3 NC and coating layer have yet to be conducted. In this study, the dynamics of hot carrier and charge carrier of CsPbBr3 nanocrystal with various MO2 (M = Si, Ti, Sn) coating layers have been comprehensively studied. Combined transient optical characterizations (time-resolved photoluminescence and ultrafast transient absorption) and photoelectrochemical measurements reveal that coating with insulating SiO2 accelerates the hot carrier relaxation and enhances the radiative recombination by passivating surface traps, whereas efficient charge-carrier separation and extraction are observed after coating with SnO2 and TiO2. The electron injection from CsPbBr3 NC to SnO2 (1.14 × 108 s–1) is 2-fold faster than to TiO2 (5.4 × 107 s–1) owing to the lower conduction band edge and the higher electron mobility of SnO...

The proper energy band structure and excellent visible-light responses enable halide perovskites as potential photocatalysts for CO2 reduction, but the conversion efficiency is still low due to the serious radiative recombination, low CO2 capturing ability, and poor stability. Here we illustrate the design and synthesis of a halide perovskite@metal–organic framework (MOF) composite photocatalyst with enhanced CO2 reduction activity. A facile in situ synthetic procedure is employed to directly grow a zinc/cobalt-based zeolitic imidazolate framework (ZIF) coating on the surface of CsPbBr3 quantum dots. The CsPbBr3@ZIF composite shows largely improved moisture stability, CO2 capturing ability, and charge separation efficiency. Moreover, the catalytic active Co centers in ZIF-67 can further accelerate the charge separation process and activate the adsorbed CO2 molecules, which leads to enhanced catalytic activity for gaseous CO2 reduction. This work would provide new insight for designing excellent perovskite...

The cesium lead halide perovskite nanocrystal (NC) has shown admirable potential in promising optoelectronic applications. However, the notorious toxicity of lead severely hinders its further commercialization. Herein, we report facile synthesis of a lead-free Cs2PdBr6 perovskite NC without the assistance of long-chain organic ligand. Such Cs2PdBr6 NCs with an average particle diameter of 2.8 nm and thickness of 1–2 unit cells possess a narrow bandgap of 1.69 eV and outstanding stability toward light, humidity, and heat, which enables it to be a promising photoelectrical material. The charge carrier dynamics are also analyzed via time-resolved photoluminescence decay and transient absorption spectroscopy to guide forthcoming material optimizations. Lastly, a fast anion-exchange method is adopted to prepare the Cs2PdI6 NC. Overall, this work inspires an eminent prototype to synthesize ingenious lead-free, narrow-bandgap, and stable perovskite NCs.

The power conversion efficiencies (PCEs) of perovskite solar cells (PSCs) are already higher than those of other thin-film photovoltaic technologies, but the high-efficiency cells are based on complicated device architectures with multiple layers of coating. A promising strategy to commercialize this emerging technology is to simplify the device structure while simultaneously maintaining high-efficiency. Charge transport layers (CTLs) are generally indispensable for achieving high-performance PSCs, but the high cost and possibility of instability hinder the mass production of efficient, stable PSCs in a cost-effective manner. The ambipolar carrier transfer characteristic of perovskite materials makes it possible to fabricate efficient PSCs even in the absence of electron and/or hole transport layers. Encouragingly, the reported PCEs of CTL-free PSCs are already over 20%. However, it is still a mystery about why and how CTL-free devices can work efficiently. Here, we summarize the recent strategies developed to improve the performance of CTL-free PSCs, aiming at strengthening the comprehensive understanding of the fundamental carrier dynamics, heterojunction merits and device physics behind these mysteriously simple yet efficient devices. This review sheds light on identifying the limiting and determining factors in achieving high-efficiency CTL-free devices, and proposes some empirical charge transport models (e.g. p-type doping of perovskites for HTL-free PSCs, n-type doping of perovskites for ETL-free PSCs, constructing efficient p-n heterojunctions and/or homojunctions at one side/interface or employing perovskite single crystal-based lateral geometry for both HTL and ETL-free PSCs, etc.) that are useful to further improve device performance. In addition, an insightful perspective for the future design and commercial development of large-scale, efficient and stable optoelectronic devices by employing carbon electrodes is provided.

In this report, a novel zero-dimensional CsPbBr3 nanocrystal (CsPbBr3 NC)/two-dimensional Pd nanosheet (Pd NS) composite photocatalyst is prepared to afford efficient and stable photocatalytic gaseous CO2 reduction in the presence of H2O vapor under visible light illumination. Pd NS herein acts as an electron reservoir to quickly separate the electron–hole pairs in CsPbBr3 NC through a Schottky contact, and provides an ideal site for CO2 reduction reactions. A highest electron consumption rate of 33.79 μmol g–1 h–1 is achieved by the CsPbBr3 NC/Pd NS composite, which corresponds to a 2.43-fold enhancement over pristine CsPbBr3 NC (9.86 μmol g–1 h–1), thus providing a practical and universal solution for the halide perovskite materials to boost the photocatalytic performance through semiconductor/metal design.

Cutaneous squamous cell carcinoma (CSCC), an epidermal keratinocyte-derived skin tumor, is one of the most leading causes of cancer-associated morbidity and mortality worldwide. Long noncoding RNAs have emerged as key regulators of tumor development and progression. Recent studies have identified LINC00319, a long intergenic noncoding RNA, as an oncogene in lung cancer. However, the biological role of LINC00319 in CSCC remains largely unknown. The current study aimed to explore the role of LINC00319 in CSCC and uncover the molecular mechanisms. In current study, we found that LINC00319 was significantly upregulated in both CSCC tissues and cell lines. Besides, the χ2 test showed that increased expression of LINC00319 was associated with larger tumor size, advanced TNM stage, and lymphovascular invasion. Gain-of-function and loss-of-function approaches were applied to investigate the effects of LINC00319 on CSCC cells. Functional studies demonstrated that LINC00319 promoted CSCC cell proliferation, accelerated cell cycle progression, facilitated cell migration and invasion, and inhibited cell apoptosis. Mechanistic studies revealed that LINC00319 exerts its oncogenic functions in CSCC via miR-1207-5p-mediated regulation of cyclin-dependent kinase 3. Taken together, upregulation of LINC00319 implies a potential link with poor prognosis and reflects CSCC progression. Collectively, this study may provide some evidence for LINC00319 as a candidate target in CSCC treatment.

Nanostructured TiO2 with differentiate morphologies has attracted tremendous attention due to its wide band-gap nature as well as outstanding optical and electric properties for solar-driven light-to-electricity conversion application. Layered-stacking TiO2 film such as double-layer, tri-layer, quadruple- or quintuplicate-layer, is highly desirable to the design of high-performance semiconductor material photoanodes and the development of advanced photovoltaic devices. In this minireview, we will summarize the recent progress and achievements on proof-of-concept of layered-stacking TiO2 films (LTFs) for solar cells with emphasis on the tailored properties and synergistic functionalization of LTFs, such as optimized sensitizer adsorption, broadened light confinement as well as facilitated electron transport characteristics. Various demonstrations of LTFs photovoltaic systems provide lots of possibilities and flexibilities for more efficient solar energy utilization that a wide variety of TiO2 with distinguished morphologies can be integrated into differently structured photoanodes with synergistic and complementary advantages. This key structure engineering technology will also pave the way for the development of next generation state-of-the-art electronics and optoelectronics. Finally, from our point of view, we conclude the future research interest and efforts for constructing more efficient LTFs as photoelectrode, which will be highly warranted to advance the solar energy conversion process.

ABX3-type organic-inorganic hybrid halide perovskite materials have been recognized as promising candidates for optoelectronic applications. However, poor stability of organic-inorganic hybrid perovskite hinders their forward long-term utilization and hence an effective strategy is needed to replace the organic part with an inorganic cation. Herein, all inorganic CsPbI3 nanowires with a diameter of 50–100 nm are synthesized on fluorine-doped tin oxide glass via a simple solution-dipping process, which are further transformed into CsPbBr3 nanowires through a solution-phase halide exchange method. A phase change from non-perovskite to perovskite structure is observed during the ion substitution process of I− by Br−, which is elaborated by X-ray diffraction, absorption and photoluminescence spectra. We for the first time apply the as-formed CsPbI3 and CsPbBr3 nanowires into perovskite solar cells, yielding power conversion efficiency of 0.11% and 1.21%, respectively. The inorganic CsPbBr3 nanowire solar cell shows impressive stability which still remains 99% of the initial power conversion efficiency even after 5500 h aging.

Exploration of active, cost-effective, and stable non-noble electrocatalysts for efficient hydrogen evolution is essential for sustainable energy systems. In this study, we report the synthesis of molybdenum phosphide nanowires on carbon cloth (MoP NW/CC) by a facile iron-assisted strategy; the as-obtained MoP NW/CC is a robust hydrogen evolution catalyst with high activity. Results reveal that the added iron can promote the upward growth of ferrum molybdenum oxide (Fe–Mo–O) nanowire precursor on carbon cloth and morphological maintenance during the in situ gas–solid phosphidation process; thus, iron plays a key role in engineering the morphology of the catalysts. As a novel 3D hydrogen evolution cathode, the as-obtained MoP NW/CC electrode exhibits a low onset potential of 72 mV, low overpotential of 173 mV for high current density of 100 mA cm−2, a small Tafel slope of 53.3 mV dec−1, and superior durability in an acidic electrolyte. Additionally, this electrode displays considerable HER activity and promising stability in alkaline and neutral media. This outstanding HER activity for MoP NW/CC can be ascribed to its unique nanowire morphology with a large surface area exposing ample active sites and superior charge transport kinetics. Importantly, in our study, a facile and effective approach has been developed for regulating the morphology of transition-metal phosphides.

Cesium lead iodide perovskite (CsPbI3) has been proposed as an efficient alternative to modify the instability of methylammonium lead iodide (MAPbI3) under thermal and humidity stress. However, three-dimensional (3D) cesium lead iodide forms an undesirable non-perovskite structure with a wide bandgap at ambient atmosphere. Herein, dimension engineering is employed by introducing a bulky ammonium cation to form stable 2D cesium lead iodide perovskite BA2CsPb2I7 (BA = CH3(CH2)3NH3), which not only exhibits prominent optoelectronic properties, but also possesses superior structural and compositional stability to 3D CsPbI3 and MAPbI3 under the pressure of heat and humidity. The current 2D BA2CsPb2I7 shows excellent stability after exposure to 30% relative humidity for 30 days or upon heating at 85 °C for 3 days. In addition, the corresponding BA2CsPb2I7 based planar perovskite solar cells retain 92% of the initial power conversion efficiency (PCE) after aging for over 30 days without any encapsulation, demonstrating the up-scalability of 2D perovskite compounds as stable and efficient light-absorbing materials for perovskite solar cells and other optoelectronic applications.

Designing and exploring efficient and stable non-noble bifunctional catalysts by nanostructure modification and chemical composition tuning for water splitting is of critical importance for sustainable resources. Herein, pure phase nickel molybdenum phosphide (NiMoP2) nanowires on carbon cloth are successfully synthesized through a simple and highly reproducible in situ P/O exchange process. Such a NiMoP2 nanowire catalyst requires low overpotentials of 199 and 330 mV to obtain a high current density of 100 mA cm−2 towards the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), respectively, and is among the most active HER and OER electrocatalysts yet reported. The bifunctional NiMoP2 is used as both anode and cathode catalysts in a two-electrode water electrolysis configuration, which delivers a current density of 10 mA cm−2 under a potential of 1.67 V. Furthermore, the overall water-splitting of the bifunctional NiMoP2 nanowire catalyst is further driven by a dry battery with a nominal voltage of 1.5 V which exhibits excellent performance and durability in a strong alkaline electrolyte.