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Highlights: The development history and the reaction mechanisms involved in dual-ion batteries (DIBs) are reviewed. The optimization strategies toward DIB electrodes and electrolytes and their energy-related applications are highlighted. The research challenges and possible development directions of DIBs are outlined. There has been increasing demand for high-energy density and long-cycle life rechargeable batteries to satisfy the ever-growing requirements for next-generation energy storage systems. Among all available candidates, dual-ion batteries (DIBs) have drawn tremendous attention in the past few years from both academic and industrial battery communities because of their fascinating advantages of high working voltage, excellent safety, and environmental friendliness. However, the dynamic imbalance between the electrodes and the mismatch of traditional electrolyte systems remain elusive. To fully employ the advantages of DIBs, the overall optimization of anode materials, cathode materials, and compatible electrolyte systems is urgently needed. Here, we review the development history and the reaction mechanisms involved in DIBs. Afterward, the optimization strategies toward DIB materials and electrolytes are highlighted. In addition, their energy-related applications are also provided. Lastly, the research challenges and possible development directions of DIBs are outlined. [ABSTRACT FROM AUTHOR]

In the pursuit of better electrode kinetics and mass transportation for electrochemical energy applications, 3D graphene-based electrodes have been receiving increasing research interest. Distinguished from other kinds of 3D graphene structures, the well-developed, vertically aligned graphene nanosheet arrays (VAGNAs) could be grown on a variety of substrates by plasma-enhanced chemical vapor deposition (PECVD), forming a 3D interconnected structure with intimate contact with substrates and largely exposed edges, and easily accessible open surfaces of the graphene nanosheets. Ascribing to the combined superior inherent properties of graphene and the special structure configuration, e.g., large surface area, excellent electron transfer capability, outstanding mechanical strength, great chemical and thermal stabilities, and enhanced electrochemical activity, VAGNAs have demonstrated promising applications in supercapacitors, batteries, and fuel cell catalysts. This progress report provides a brief review on the nucleation and growth of VAGNAs, their growth mechanism and properties, and highlights the recent important progress in their electrochemical energy conversion and storage applications, in the views of their pros and cons in comparison with other 3D graphene-based structures. Challenges and perspectives for future advance are discussed in the end. [ABSTRACT FROM AUTHOR]

• Boron-doped aromatics have demonstrated valuable optoelectrical application in the past few years. In this mini review, our focus was on three-coordinated boron-doped aromatics. The recent progress of their applications in organic light-emitting diodes, organic field-effect transistors, chemical sensing, imaging and organic photovoltaics were highlighted. The structure and optoelectronic performance of three-coordinated boron-doped aromatic compounds were discussed, in order to gain a fundamental insight into the design strategy of the molecules and the related applications. Boron-doped polycyclic aromatic hydrocarbons are an emerging class of material. The incorporation of electrophilic boron atoms into aromatic system can modify the electronic property, leading to strutures with new photophysical and optoelectronic properties. The advances in synthetic chemistry promoted the generation of new boron-doped aromatic species and their applications in optoelectronics have been further explored. This review highlights the recent progress of three-coordinated boron-doped aromatic compounds for their applications in organic light-emitting diodes, organic field-effect transistors, chemical sensing, imaging and organic photovoltaics. [ABSTRACT FROM AUTHOR]

Abstract: ZnS nanorings have been synthesized via thermal evaporation of ZnS powders at 1050°C for the first time. The ZnS nanorings grew along the [] direction with a high density of stacking faults along the [0001] direction. The ZnS nanorings were believed to be formed by strain induced bending. This mechanism of ZnS nanoring formation is totally different from those proposed for the formation of ZnO, ZnSe, AlN and GaN nanorings via coiling of their polar surface and long-rang electrostatic interaction. This synthesis method of ZnS nanoring suggests that similar ring-like structures of other II–VI semiconducting nanomaterials may be synthesized. [Copyright &y& Elsevier]

Sodium‐ion batteries (SIBs) suffer from sluggish kinetics, large volume change, and limited specific capacity due to the large radius of Na+. These issues can be solved through using covalent organic frameworks (COFs) as electrodes. Herein, an azatriangulenetrione‐containing COF (denoted as CityU‐33) was designed and synthesized as an electrode material for SIBs. Due to its inherent abundance of multiple redox‐active sites and fast intercalation kinetics, CityU‐33 delivered a high discharge capacity of 410.4 mAh g−1 at 0.1 A g−1 and showed remarkable long‐term cycling stability, where a discharge capacity of 288 mAh g−1 at 0.2 A g−1 with 97 % retention over 2000 cycles was achieved, making it the top COF electrode material for SIBs. [ABSTRACT FROM AUTHOR]

Extending covalent organic frameworks (COFs) into crystalline carbon‐free covalent backbones is an important strategy to endow these materials with more exotic functions. Integrating metal‐free inorganic and organic components into one covalent framework is an effective way to address the issue of poor thermal/solvent stability in the field of nonlinear optics (NLO). However, constructing such structures is very challenging. Here, we linked 3‐connected nods (BO3) and 2‐connected organic building blocks (Te(Ph)2) together to produce colorless single crystals (size up to 400 μm) of a three‐dimensional (3D) chiral covalent framework (CityU‐22). The single‐crystal X‐ray diffraction (SCXRD) analysis reveals that CityU‐22 has a non‐carbon Te−O−B−O bond‐based network with the srs topology. The chiral CityU‐22 displays good stability under the treatment of different common solvents or heat (the decomposition temperature above 300 °C). Due to its non‐π‐conjugated backbone (−Te−O−B−O−), CityU‐22 shows an ultraviolet NLO behavior with a second‐harmonic generation (SHG) response similar to KH2PO4 (KDP). [ABSTRACT FROM AUTHOR]

Extending covalent organic frameworks (COFs) into crystalline carbon‐free covalent backbones is an important strategy to endow these materials with more exotic functions. Integrating metal‐free inorganic and organic components into one covalent framework is an effective way to address the issue of poor thermal/solvent stability in the field of nonlinear optics (NLO). However, constructing such structures is very challenging. Here, we linked 3‐connected nods (BO3) and 2‐connected organic building blocks (Te(Ph)2) together to produce colorless single crystals (size up to 400 μm) of a three‐dimensional (3D) chiral covalent framework (CityU‐22). The single‐crystal X‐ray diffraction (SCXRD) analysis reveals that CityU‐22 has a non‐carbon Te−O−B−O bond‐based network with the srs topology. The chiral CityU‐22 displays good stability under the treatment of different common solvents or heat (the decomposition temperature above 300 °C). Due to its non‐π‐conjugated backbone (−Te−O−B−O−), CityU‐22 shows an ultraviolet NLO behavior with a second‐harmonic generation (SHG) response similar to KH2PO4 (KDP). [ABSTRACT FROM AUTHOR]

Phototheranostics with second near‐infrared (NIR‐II) emissions show great potential for disease diagnosis and imaging‐guided phototherapy owing to deep tissue penetration, high imaging resolution, and excellent tumor eradication. Recently, molecular conjugation engineering and J‐aggregation have been used to construct organic NIR‐II materials. However, these molecules generally have extensive conjugation and large molecular weight in the range of 700–1700 g mol−1, requiring complicated molecular design and synthesis. Herein, a NIR‐II emissive through‐space charge‐transfer (TSCT) nanoparticle (NP) using short‐conjugated donor‐acceptor (D‐A) molecules (TTP) is reported for high‐performance bioimaging and cancer phototheranostics. Owing to the short conjugation of the TTP molecule with a small molecular weight of only 518 g mol−1, the TTP monomer possesses visible absorption and first near‐infrared (NIR‐I) emission. Upon forming NPs in water, the efficient TSCT between TTP monomers leads to significantly red‐shifted absorption to the NIR‐I and emission to the NIR‐II region with a tail that extends to 1400 nm. TTP NPs are employed in NIR‐II in vivo blood‐vessel bioimaging and cancer phototheranostics successfully. This work introduces a facile strategy to construct NIR‐II emissive NPs based on short‐conjugated D‐A molecules for high‐performance biomedical applications. [ABSTRACT FROM AUTHOR]

Excellent bipolar carrier transport properties of 2,7-dipyrenyl-9,9′-dimethyl-fluorene (DPF) have been elucidated by using different device structures. A nondoped device using DPF as host emitter showed highly-efficient blue emission with a maximum efficiency of 6.0 cd/A and CIE coordinates of x=0.15 and y=0.19. Another device based on rubrene-doped DPF as emission layer gave pure high-efficiency white emission with good color stability, a maximum efficiency of 10.5 cd/A, and CIE coordinates of x=0.28 and y=0.35. The excellent bipolar transport capability and high performance as both emitter and host suggest that DPF is an efficient and versatile material for various applications in organic light-emitting devices. [ABSTRACT FROM AUTHOR]

The multiple mortise‐and‐tenon joint parts are the core factors to provide the structural stability and diversity of Chinese Luban locks; however, constructing such structures is very challenging. Herein, single crystals of a covalent organic nanoribbon (named CityU‐27) are prepared through the assembly of hexahydroxytriphenylene (HHTP), 4,4′‐vinylenedipyridine (BYE), and phenylboronic acid (BA) together through dative boron←nitrogen (B←N) bonds. The single‐crystal X‐ray diffraction analysis indicates that CityU‐27 has a covalent organic nanoribbon structure, where each nanoribbon forms multiple and tight π–π interactions with four neighboring others to generate a Luban lock‐like configuration. CityU‐27 has been demonstrated to be an efficient photocatalyst in a one‐pot tandem reaction of hydrogen evolution reaction (HER) and semi‐hydrogenation reaction of alkynes in series to produce olefins without any additional photosensitizers and co‐catalysts (metal‐free). [ABSTRACT FROM AUTHOR]

The multiple mortise‐and‐tenon joint parts are the core factors to provide the structural stability and diversity of Chinese Luban locks; however, constructing such structures is very challenging. Herein, single crystals of a covalent organic nanoribbon (named CityU‐27) are prepared through the assembly of hexahydroxytriphenylene (HHTP), 4,4′‐vinylenedipyridine (BYE), and phenylboronic acid (BA) together through dative boron←nitrogen (B←N) bonds. The single‐crystal X‐ray diffraction analysis indicates that CityU‐27 has a covalent organic nanoribbon structure, where each nanoribbon forms multiple and tight π–π interactions with four neighboring others to generate a Luban lock‐like configuration. CityU‐27 has been demonstrated to be an efficient photocatalyst in a one‐pot tandem reaction of hydrogen evolution reaction (HER) and semi‐hydrogenation reaction of alkynes in series to produce olefins without any additional photosensitizers and co‐catalysts (metal‐free). [ABSTRACT FROM AUTHOR]

Tin halide perovskites are the most promising candidate materials for lead‐free perovskite solar cells (PSCs) thanks to their low toxicity and ideal band gap energies. The introduction of 2D/3D mixed perovskite phases in tin‐based PSCs (TPSCs) has proven to be the most effective approach to improving device efficiency and stability. However, a 2D perovskite phase normally shows relatively low carrier mobility, which will be unfavorable for carrier transfer in the devices. In this work, we used a thiophene‐based cation 2‐(thiophen‐3‐yl)ethan‐1‐aminium (3‐TEA) as a spacer to form a novel 2D perovskite phase in TPSCs, which shows the most promising effect on the performance enhancement in comparison with other cations like 2‐(thiophen‐2‐yl)ethan‐1‐aminium (2‐TEA) and benzene‐based 2‐phenylethan‐1‐aminium (PEA). Theoretical calculations reveal that 3‐TEA enables the most compact crystal packing of [SnI6]4− octahedral layers, resulting in the lowest hole effective mass and formation energy in the 2D phase. This effect significantly enhances device efficiency and stability by facilitating more efficient carrier transfer within the 2D phase. These findings indicate that thiophene‐based 2D perovskites are well‐suited for high‐performance TPSCs. [ABSTRACT FROM AUTHOR]

Due to the shortage of lithium resources, current lithium-ion batteries are difficult to meet the growing demand for energy storage in the long run. Rechargeable aqueous aluminum ion (Al3+) electrochemistry has the advantages of abundant resources, high safety, environmental friendliness, and high energy/power density. It is, therefore an ideal choice for alternative energy storage devices. However, Al3+-based technology is still in the preliminary stage, and there are various challenges. In reality, its kinetics and reversibility have long been disturbed by the strong electrostatic field of Al3+ and the parasitic side reactions of aqueous electrolytes. This paper first summarizes the history of aqueous aluminum ion batteries/capacitors (AAIBs/AAICs) and analyzes the challenges faced by cathode, anode, and electrolyte. Then, the state-of-the-art research progress, design strategies, and limitations of the cathode, anode, electrolyte, and Al3+-based energy storage devices are comprehensively introduced, and their structure, performance, and reaction mechanisms are discussed. Finally, the future design of AAIBs/AAICs with long life, high reversibility, and high energy/power density has been prospected, and promising research directions are pointed out. [ABSTRACT FROM AUTHOR]

Deep‐blue multi‐resonance (MR) emitters with stable and narrow full‐width‐at‐half‐maximum (FWHM) are of great importance for widening the color gamut of organic light‐emitting diodes (OLEDs). However, most planar MR emitters are vulnerable to intermolecular interactions from both the host and guest, causing spectral broadening and exciton quenching in thin films. Their emission in the solid state is environmentally sensitive, and the color purity is often inferior to that in solutions. Herein, a molecular design strategy is presented that simultaneously narrows the FWHM and suppresses intermolecular interactions by combining intramolecular locking and peripheral shielding within a carbonyl/nitrogen‐based MR core. Intramolecularly locking carbonyl/nitrogen‐based bears narrower emission of 2,10‐dimethyl‐12,12‐diphenyl‐4H‐benzo[9,1]quinolizino[3,4,5,6,7‐defg]acridine‐4,8(12H)‐dione in solution and further with peripheral‐shielding groups, deep‐blue emitter (12,12‐diphenyl‐2,10‐bis(9‐phenyl‐9H‐fluoren‐9‐yl)−4H‐benzo[9,1]quinolizino[3,4,5,6,7‐defg]acridine‐4,8(12H)‐dione, DPQAO‐F) exhibits ultra‐pure emission with narrow FWHM (c.a., 24 nm) with minimal variations (∆FWHM ≤ 3 nm) from solution to thin films over a wide doping range. An OLED based on DPQAO‐F presents a maximum external quantum efficiency (EQEmax) of 19.9% and color index of (0.134, 0.118). Furthermore, the hyper‐device of DPQAO‐F exhibits a record‐high EQEmax of 32.7% in the deep‐blue region, representing the first example of carbonyl/nitrogen‐based OLED that can concurrently achieve narrow bandwidth in the deep‐blue region and a high electroluminescent efficiency surpassing 30%. [ABSTRACT FROM AUTHOR]

Inspired by dative boron‐nitrogen (B←N) bonds proven to be the promising dynamic linkage for the construction of crystalline covalent organic polymers/frameworks (COPs/COFs), we employed 1,4‐bis(benzodioxaborole) benzene (BACT) and N,N′‐Di(4‐pyridyl)‐1,4,5,8‐naphthalenetetracarboxdiimide (DPNTCDI) as the corresponding building blocks to construct a functional COP (named as CityU‐25), which had been employed as an anode in rechargeable lithium ion batteries. CityU‐25 displayed an excellent reversible lithium storage capability of 455 mAh/g after 170 cycles at 0.1 A/g, and an impressive one of 673 mAh/g after 720 cycles at 0.5 A/g. These findings suggest that CityU‐25 is a standout candidate for advanced battery technologies, highlighting the potential application of this type of materials. [ABSTRACT FROM AUTHOR]

Inspired by dative boron‐nitrogen (B←N) bonds proven to be the promising dynamic linkage for the construction of crystalline covalent organic polymers/frameworks (COPs/COFs), we employed 1,4‐bis(benzodioxaborole) benzene (BACT) and N,N′‐Di(4‐pyridyl)‐1,4,5,8‐naphthalenetetracarboxdiimide (DPNTCDI) as the corresponding building blocks to construct a functional COP (named as CityU‐25), which had been employed as an anode in rechargeable lithium ion batteries. CityU‐25 displayed an excellent reversible lithium storage capability of 455 mAh/g after 170 cycles at 0.1 A/g, and an impressive one of 673 mAh/g after 720 cycles at 0.5 A/g. These findings suggest that CityU‐25 is a standout candidate for advanced battery technologies, highlighting the potential application of this type of materials. [ABSTRACT FROM AUTHOR]

Antimicrobial photodynamic therapy (aPDT) has emerged as an appealing therapeutic option against biofilm infections. However, effectively penetrating the dense barrier of biofilm and anchoring bacteria to achieve biofilm elimination and wound healing under hypoxic environments remains a challenge for aPDT. Herein, three type I/II Hypocrellin B (HB)‐cationic photosensitizers (HB‐P, HB‐TP, and HB‐TTP) are designed based on a multi‐cationic long chains molecular engineering strategy. With an increasing number of introduced cations, the reactive oxygen species (ROS) production and bacterial‐anchoring abilities of HB‐cationic photosensitizers are greatly enhanced. Notably, HB‐TTP demonstrates higher type I/II aPDT activity and broad‐spectrum antibacterial properties. Furthermore, to effectively address the conundrum of healing biofilm‐infected wounds, a ROS‐responsive core‐shell microneedle (HB‐TTP&EGF@MN) is designed by biphasically integrating HB‐TTP and growth factor. When the microneedle penetrates biofilm, the shell quickly dissolves and releases HB‐TTP to achieve biofilm removal under laser irradiation. The core is subsequently degraded slowly in the presence of endogenous ROS within the wound, facilitating a sustained release of growth factor to promote wound tissue regeneration. This work not only provides an effective strategy for the rational design of efficient antimicrobial agents but also proposes innovative ideas for the development of controlled‐release pharmaceutical materials to synergize against biofilm infections. [ABSTRACT FROM AUTHOR]

Zinc‐ion batteries (ZIBs) have attracted wide attention due to their low redox potential, high capacity, and intrinsic safety. However, key issues such as zinc dendrite growth, corrosion, and passivation on zinc anode detrimentally affect the electrochemical performance. Herein, as proof of a concept of oligopeptide, glutathione with functional groups including –NH2 and −SH is introduced as an electrolyte additive to construct a multifunctional electrode–electrolyte interface layer on the zinc anode. A protonated amino group (NH3+) is formed, which prevents the adsorption of water molecules on the Zn anode, building a hydrophobic interface layer and thus attenuating corrosion. Moreover, the strong interaction between the −SH and the zinc allows glutathione molecules to be tightly anchored to the electrode surface, constructing a robust interface layer. Consequently, a long cycling life of nearly 3000 h at 1 mA cm−2 for the Zn||Zn symmetric battery is achieved, and a stable cycling life of 1600 h is demonstrated at 3 mA cm−2. Furthermore, Zn||activated carbon (AC) hybrid capacitor with the glutathione‐containing electrolyte runs stably for nearly 28 000 cycles at 5 A g−1, among the best results of reported Zn hybrid capacitors. [ABSTRACT FROM AUTHOR]

The creation of versatile platforms for developing dual‐channel near‐infrared fluorescent (NIRF) and photoacoustic (PA) probes, especially those engineered to minimize channel crosstalk, is crucial for precise biomarker detection. However, such platforms remain scarce. To bridge this gap, this study introduces an innovative cyanine‐based platform, CySN. The CySN platform showcases remarkable wavelength‐shifting properties, including large fluorescent modality shift (68 nm) and PA modality shift (145 nm) after the decaging reaction. These substantial changes lead to an exceptionally high ratiometric NIRF change of 603‐fold and ratiometric PA change of 261‐fold. Leveraging the CySN platform, dual‐channel NIRF/PA probes have been successfully developed for detecting both small molecule biomarker (H2O2) and enzyme biomarker (esterase). These probes demonstrate the ability to detect their targets through dual‐channel NIRF/PA detection with high sensitivity and selectivity in vitro. Furthermore, the probes effectively harness NIRF signals to image target analytes in living cells. Notably, the probes demonstrate the capability to accurately diagnose tumors by detecting tumor markers (H2O2 and esterase), revealing a 3.6 to 7‐fold ratiometric PA enhancement over normal tissue. Therefore, the CySN platform holds the potential to further advance the development of dual‐channel NIRF/PA probes for biomolecule detection in disease diagnosis. [ABSTRACT FROM AUTHOR]

Alloying the metal halide perovskite composition has become a key strategy for engineering the optoelectronic properties for various applications. However, the difference in complexation between ions poses a threat to crystal stability. In particular, the phase segregation in wide‐bandgap perovskites (WBG) with mixed halides is the major challenge in multi‐junction photovoltaic devices. Here, a systematic study is reported on the origin of phase segregation in a prototypical mixed halide perovskite (MHP) MAPbI2Br. It is found that the crystallinity and surface morphology are not associated with the lattice stability. Using highly sensitive external quantum efficiency (s‐EQE) measurement, it is found that the defects in the MHP are mainly associated with the Pb2+ and I−/Br− ions. Consistently, density‐function‐theory (DFT) calculation confirms that the MAPbI2Br surface is dominated by the metal‐halide components, and the imbalanced surface charge is responsible for the lattice instability. The role of physical and chemical passivation approaches in MHP is further investigated. The former limits the ion migration and allows dissociated ions to recover to their corresponding defective sites, whereas the latter lowers the surface energy by neutralizing the charge density on the lattice surface. This work brings insight into the phase segregation and passivation mechanisms in MHP. [ABSTRACT FROM AUTHOR]

The controllable photocatalytic C−C coupling of methanol to produce ethylene glycol (EG) is a highly desirable but challenging objective for replacing the current energy‐intensive thermocatalytic process. Here, we develop a metal‐free porous boron nitride catalyst that demonstrates exceptional selectivity in the photocatalytic production of EG from methanol under mild conditions. Comprehensive experiments and calculations are conducted to thoroughly investigate the reaction mechanism, revealing that the OB3 unit in the porous BN plays a critical role in the preferential activation of C−H bond in methanol to form ⋅CH2OH via a concerted proton‐electron transfer mechanism. More prominent energy barriers are observed for the further dehydrogenation of the ⋅CH2OH intermediate on the OB3 unit, inhibiting the formation of some other by‐products during the catalytic process. Additionally, a small downhill energy barrier for the coupling of ⋅CH2OH in the OB3 unit promotes the selective generation of EG. This study provides valuable insights into the underlying mechanisms and can serve as a guide for the design and optimization of photocatalysts for efficient and selective EG production under mild conditions. [ABSTRACT FROM AUTHOR]

The controllable photocatalytic C−C coupling of methanol to produce ethylene glycol (EG) is a highly desirable but challenging objective for replacing the current energy‐intensive thermocatalytic process. Here, we develop a metal‐free porous boron nitride catalyst that demonstrates exceptional selectivity in the photocatalytic production of EG from methanol under mild conditions. Comprehensive experiments and calculations are conducted to thoroughly investigate the reaction mechanism, revealing that the OB3 unit in the porous BN plays a critical role in the preferential activation of C−H bond in methanol to form ⋅CH2OH via a concerted proton‐electron transfer mechanism. More prominent energy barriers are observed for the further dehydrogenation of the ⋅CH2OH intermediate on the OB3 unit, inhibiting the formation of some other by‐products during the catalytic process. Additionally, a small downhill energy barrier for the coupling of ⋅CH2OH in the OB3 unit promotes the selective generation of EG. This study provides valuable insights into the underlying mechanisms and can serve as a guide for the design and optimization of photocatalysts for efficient and selective EG production under mild conditions. [ABSTRACT FROM AUTHOR]

Electrochromic devices (ECDs) show promising applications in various fields including energy‐saving smart windows, energy‐recycling batteries/supercapacitors, displays, thermal management, etc. Compared to monovalent cations (H+, Li+, Na+, and K+), multivalent‐ion carriers (Mg2+, Ca2+, Zn2+, and Al3+) can enable the ECDs with high optical contrast, high energy‐recycling capability, and attractive long‐term stability because of the multiple‐electron transfer redox. Additionally, Mg2+, Zn2+, and Al3+‐based ECDs assembled with metal anodes are exploited for applications in EC electronics, EC mirrors, flexible devices, etc. Attempts to develop multivalent‐ion ECDs can be traced to 2013. However, since 2017, the research activity in this field has surged in the world. Despite the fascinating achievements, there is still a long way from their maturity due to challenges related to the limited electrode materials and electrolytes, as well as the obscure multivalent‐ion redox mechanisms. This review aims to discuss 1) the EC mechanisms of electrode materials with multivalent ions, 2) the advantageous functionalities of multivalent‐ion ECDs, and 3) strategies developed for exploring electrode materials, electrolytes, and ECD structures. Additionally, future perspectives for remaining challenges and corresponding strategies for developing multivalent‐ion ECDs with designed functionalities are discussed. [ABSTRACT FROM AUTHOR]

Controlling the crystallization to achieve high‐quality homogeneous perovskite film is the key strategy in developing perovskite electronic devices. Here, an in situ dynamic optical probing technique is demonstrated that can monitor the fast crystallization of perovskites and effectively minimize the influence of laser excitation during the measurement. This study finds that the typical static probing technique would damage and induce phase segregation in the perovskite films during the excitation. These issues can be effectively resolved with the dynamic probing approach. It also found that the crystallization between MAPbI3 and MAPbI2Br is strikingly different. In particular, MAPbI2Br suffers from inefficient nucleation during the spin‐coating that strongly affects the uniform crystal growth in the annealing process. The commonly used pre‐heating process is found at a lower temperature not only can further promote the nucleation but also to complete the crystallization of MAPbI2Br. The role of further annealing at a higher temperature is to facilitate ion‐dissociation on the crystal surface to form a passivation layer to stabilize the MAPbI2Br lattices. The device performance is strongly correlated with the film formation mechanism derived from the in situ results. This work demonstrates that the in situ technique can provide deep insight into the crystallization mechanism, and help to understand the growth mechanism of perovskites with different compositions and dimensionalities. [ABSTRACT FROM AUTHOR]

A simple strategy to simultaneously achieve fast reverse intersystem crossing (RISC) and low non‐radiative decay rates in thermally activated delayed fluorescence (TADF) emitters is still lacking. Here, the green TADF emitters containing aromatic ketones and prepared D‐Ph and D‐PhCz containing different amounts of deuterium are deuterated to study the mechanism of deuterium on the performance improvement of TADF devices. Due to the heavy atom effect of deuterium, the non‐radiative transition rate constant (knr) of D‐Ph and D‐PhCz decreases. Most importantly, deuterium reduces the reorganization energy (λ) of (T1‐S1), which greatly improves the reverse intersystem crossing rate constant (kRISC) and the exciton utilization efficiency. The results show that the external quantum efficiency of D‐Ph and D‐PhCz increases to 25.69% and 24.92%, respectively. This study provides a simple and efficient strategy for reducing non‐radiative energy loss and increasing kRISC to achieve high‐performance TADF emitters. [ABSTRACT FROM AUTHOR]

Highlights: By employing side-chain regulation, the photothermal therapy response of conjugated diradical polymer can red-shift from near-infrared (NIR)-I to the NIR-II region. This strategy offers new radical materials in developing NIR-II photothermal materials. The conjugated diradical polymer TTB-2 receives a record-high photothermal conversion efficiency of 87.7%, far beyond the recently reported NIR-II photothermal agents. Such conjugated diradical polymer must enrich the NIR-II photothermal agents' library and provide important insight for more diradical polymer construction. The conjugated diradical polymer nanoparticles TTB-2 NPs achieve good tumor photoablation with navigation of photoacoustic imaging in the NIR-II window, without any side effect. Furthermore, the efficient photo-immunity effect prevents the pulmonary metastasis of breast cancer. Massive efforts have been concentrated on the advance of eminent near-infrared (NIR) photothermal materials (PTMs) in the NIR-II window (1000–1700 nm), especially organic PTMs because of their intrinsic biological safety compared with inorganic PTMs. However, so far, only a few NIR-II-responsive organic PTMs was explored, and their photothermal conversion efficiencies (PCEs) still remain relatively low. Herein, donor–acceptor conjugated diradical polymers with open-shell characteristics are explored for synergistically photothermal immunotherapy of metastatic tumors in the NIR-II window. By employing side-chain regulation, the conjugated diradical polymer TTB-2 with obvious NIR-II absorption was developed, and its nanoparticles realize a record-breaking PCE of 87.7% upon NIR-II light illustration. In vitro and in vivo experiments demonstrate that TTB-2 nanoparticles show good tumor photoablation with navigation of photoacoustic imaging in the NIR-II window, without any side-effect. Moreover, by combining with PD-1 antibody, the pulmonary metastasis of breast cancer is high-effectively prevented by the efficient photo-immunity effect. Thus, this study explores superior PTMs for cancer metastasis theranostics in the NIR-II window, offering a new horizon in developing radical-characteristic NIR-II photothermal materials. [ABSTRACT FROM AUTHOR]

Sodium ion‐batteries (SIBs) are considered as a class of promising alternatives to lithium‐ion batteries (LIBs) to overcome their drawbacks of limited sources and safety problems. However, the lack of high‐performance electrode materials hinders the wide‐range commercialization of SIBs. Comparing to inorganic counterparts, organic electrode materials, which are benefitted from flexibly designable structures, low cost, environmental friendliness, and high theoretical gravimetric capacities, should be a prior choice. Here, a covalent organic polymer (COP) based material (denoted as CityU‐9) is designed and synthesized by integrating multiple redox motifs (benzoquinone and thioether), improved conductivity (sulfur induction), and intrinsic insolubility (rigid skeleton). The half‐cell SIBs exhibit ultrahigh specific capacity of 1009 mAh g−1 and nearly no capacity drop after 650 cycles. The first all‐COP symmetric full‐cell shows high specific capacity of 90 mAh g−1 and excellent rate capability. This work can extend the selection of redox‐active moieties and provide a rational design strategy of high‐performance novel organic electrode materials. [ABSTRACT FROM AUTHOR]

Sodium‐based layered oxide cathodes are competitive candidates for commercial sodium‐ion batteries owing to their high theoretical capacities, low costs, and simple synthesis. P3‐type layered oxides with large open channels enable fast Na+ transport and hence good rate performance. However, the lower crystal symmetry of P3‐type oxides and variation of Na+ contents in the Na layer during desodiation/sodiation lead to large electrostatic repulsion changes between TMO2 slabs (TM=Transition Metal), resulting in irreversible phase transitions, and fast performance degradation. Herein, a potential Na+ conductor Na2SeO4 is first found that it can be easily in situ grown on P3‐Na0.45Ni0.2Mn0.8O2 to form a novel heterostructure P3‐Na0.45Ni0.2Mn0.8O2/Na2SeO4. The synergy between P3‐Na0.45Ni0.2Mn0.8O2 and Na2SeO4 functions in promoting Na+ diffusion and suppressing P3‐O3 phase transitions upon deep sodiation, which results in recorded high‐rate capability (68.2% capacity retention with retained 83.9 mAh g−1 capacity at 6400 mA g−1) and superior cycling stability (capacity retention 75% after 1000 cycles) among all reported P3‐type cathodes. Thus, it is believed that this novel heterostructure design opens a new pathway to promote practical applications for layered oxide cathodes in sodium‐ion batteries. [ABSTRACT FROM AUTHOR]

Abstract: Organic light‐emitting diodes (OLEDs) are the most successful product of organic electronics in the market and continually receive attention from scientific and industrial communities. Imidazoles have been extensively investigated for OLED applications, and demonstrated their versatility in molecular design for different functions. This review presents a summary of recent studies on imidazole (including imidazole derived moieties) derivatives, with special focus on discussing various molecular design tactics, for applications as electron‐transporting materials, emitters, and host materials in OLEDs. At last, perspectives and challenges regarding to imidazole semiconductors for electroluminescence applications are also discussed. [ABSTRACT FROM AUTHOR]

Abstract: Sky‐blue and blue‐emitting, carbazolyl functionalized, bis‐tridentate Ir(III) phosphors Cz‐1–Cz‐3 with bright emission and short radiative lifetime are successfully synthesized in a one‐pot manner. They exhibit very high photostability against UV–vis irradiation in degassed toluene, versus both green and true‐blue‐emitting reference compounds, i.e., fac‐[Ir(ppy)3] and mer‐[Ir(pmp)3]. Organic light‐emitting diodes (OLEDs) based on Cz‐2 exhibit maximum external quantum efficiency (EQE) of 21.6%, EQE of 15.1% at 100 cd m−2, and with CIEx,y coordinates of (0.17, 0.25). This study provides a conceptual solution to the exceedingly stable and efficient blue phosphor. It is promising that long lifespan blue OLED based on these emitters can be attained with further engineering of devices suitable for commercial application. [ABSTRACT FROM AUTHOR]

Stabilization of two-dimensional (2D) PEA2PbI4 (PEA is phenethylammonium) perovskite nanocrystals (PNCs) in water is achieved. By inhibiting the desorption process, the PNCs show exceptional stability for more than 2 months in PEA+ aqueous solutions. Stabilized PNCs are successfully applied for probing Cu2+ in aqueous solution. [ABSTRACT FROM AUTHOR]

As a promising candidate for next‐generation energy storage devices, Zn metal battery excels with their good safety, high specific capacity, and economic attractiveness. However, it still suffers from a narrow electrochemical window, notorious dendrite formation, and sluggish Zn ion transfer. Aqueous electrolyte engineering has been regarded as an effective way to improve these. It is shown that by adding sodium polystyrene sulfonate (PSS) polymers into a dilute 1 m Zn(OTf)2 aqueous electrolyte, compact water shells with stronger hydrogen bonding and more ordered structures are formed around the polymer chains. As a result, a fast transport channel to the zinc ions is provided. The PSS chains also protect the zinc electrode from directly contacting the water molecules and thus suppress water decomposition. With these merits, a Zn//Cu cell demonstrates a high coulombic efficiency of ≈99% after 1500 h cycling. Meanwhile, a record‐high cumulative Zn plating capacity of 10 000 mA h cm−2 is obtained using a Zn||Zn cell. In addition, the Zn//C@V2O5 full cell achieves almost 100% capacity retention after 1000 cycles. This work provides a new strategy for designing advanced electrolyte systems excelling in ion transport kinetics. [ABSTRACT FROM AUTHOR]

The ever-growing market of portable electronic devices and electric vehicles has significantly stimulated research interests on new-generation rechargeable battery systems with high energy density, satisfying safety and low cost. With unique potentials to achieve high energy density and low cost, rechargeable batteries based on metal anodes are capable of storing more energy via an alloying/de-alloying process, in comparison to traditional graphite anodes via an intercalation/de-intercalation process. However, the drawbacks of metal anodes such as high initial capacity loss and short cycling life need to be solved before commercialization. Herein, we mainly dedicate the attention on recent progresses in the metallic materials (e.g., Al, Sn, Mg, Zn, Sb and Bi) which have the best likelihood of being applied in commercial batteries and the advanced modification strategies including nanosizing, composite design, and alloy/intermetallic construction for better battery performance. In addition, the investigations of such metal anodes in some new battery systems such as sodium-ion batteries, aluminum-ion batteries, zinc-ion batteries, magnesium-ion batteries, and dual-ion batteries are further briefly reviewed. [ABSTRACT FROM AUTHOR]

One important challenge in dye-sensitized solar cells (DSSCs) is to design and construct low-cost counter electrodes (CEs) with good electrocatalytic performance. In this work, a one-step solvothermal method was used to prepare cobalt-nickel (Co-Ni) based ternary selenides with different Co and Ni ratios. Co-Ni based ternary selenide films were fabricated by simple spray deposition for applications as low-cost and high-performance CEs in DSSCs. Electrochemical measurements demonstrate that the Co-Ni based ternary selenide CEs exhibit high electrocatalytic activity and strong charge-transfer ability for the reduction of I 3 − due to the synergistic effect between Co and Ni ions in Co-Ni based ternary selenides. In particular, Co 0.42 Ni 0.58 Se CE shows the higher electrocatalytic activity than other Co-Ni based ternary selenide CEs and platinum (Pt) CE. Furthermore, the DSSC with Co 0.42 Ni 0.58 Se CE exhibits photoelectrical conversion efficiency (PCE) of 6.15%, which is considerably higher than that of the DSSC with Pt CE (5.53%). [ABSTRACT FROM AUTHOR]

Solar‐driven CO2 reduction reaction (CO2RR) with water into carbon‐neutral fuels is of great significance but remains challenging due to thermodynamic stability and kinetic inertness of CO2. Biomass‐derived nitrogen‐doped carbon (N‐Cb) have been considered as promising earth‐abundant photocatalysts for CO2RR, although their activities are not ideal and the reaction mechanism is still unclear. Herein, an efficient catalyst is developed for CO2‐to‐CO conversion realized on diverse N‐Cb materials with hierarchical pore structures. It is demonstrated that the CO2‐to‐CO conversion preferentially takes place on positively charged carbon atoms next to pyridinic‐N using two representatives treated pollens with the largest difference in pyridinic‐N density and N content as model photocatalysts. Systematic experimental results indicate that surface local electric field originating from charge separation can be boosted by hierarchical pore structures, doped N, as well as pyridinic‐N. Mechanistic studies reveal that positively charged carbon atoms next to pyridinic‐N serve as active sites for CO2RR, reduce the energy barrier on the formation of CO*, and facilitate the CO2RR performance. All these benefits cooperatively contribute to treated chrysanthemum pollen catalyst exhibiting excellent CO formation rate of 203.2 µmol h−1 g−1 with 97.2% selectivity in pure water vapor. These results provide a new perspective into CO2RR on N‐Cb, which shall guide the design of nature‐based photocatalysts for high‐performance solar‐fuel generation. [ABSTRACT FROM AUTHOR]

Solid electrolyte interphases (SEIs) play a crucial role in keeping sodium metal anodes (SMAs) intact and improving battery life. However, the SEIs arising from irreversible reactions between metallic Na and electrolytes fail to suppress Na dendrite growth and have sluggish Na+ kinetics. Herein, a functionalized separator modified by a sp2 carbon conjugated‐covalent organic framework (sp2c‐COF) is proposed to induce a robust SEI. X‐ray photoelectron spectroscopy (XPS) analyses and theoretical calculations demonstrate that the SEI is rich in NaF because the structure of NaPF6 is unstable due to influences from the COF separator. In situ observations show that the Na dendrite is effectively suppressed even at a high current density of 20 mA cm−2. Satisfactorily, the COF separator exhibits a high transference number of 0.78, achieving a fast Na plating/stripping process. Based on these superiorities, a symmetric cell Na|COF|Na shows stable cycling for over 1500 h at 20 mA cm−2. In addition, full cells Na|COF|NaTi2(PO4)3 (NTPO) present good rate performance (30 and 50 C) and excellent cycling stability over 5000 cycles at 5 and 10 C. The application of COFs to improve SMAs in this work demonstrates a new strategy for improving sodium metal batteries. [ABSTRACT FROM AUTHOR]

Solid electrolyte interphases (SEIs) play a crucial role in keeping sodium metal anodes (SMAs) intact and improving battery life. However, the SEIs arising from irreversible reactions between metallic Na and electrolytes fail to suppress Na dendrite growth and have sluggish Na+ kinetics. Herein, a functionalized separator modified by a sp2 carbon conjugated‐covalent organic framework (sp2c‐COF) is proposed to induce a robust SEI. X‐ray photoelectron spectroscopy (XPS) analyses and theoretical calculations demonstrate that the SEI is rich in NaF because the structure of NaPF6 is unstable due to influences from the COF separator. In situ observations show that the Na dendrite is effectively suppressed even at a high current density of 20 mA cm−2. Satisfactorily, the COF separator exhibits a high transference number of 0.78, achieving a fast Na plating/stripping process. Based on these superiorities, a symmetric cell Na|COF|Na shows stable cycling for over 1500 h at 20 mA cm−2. In addition, full cells Na|COF|NaTi2(PO4)3 (NTPO) present good rate performance (30 and 50 C) and excellent cycling stability over 5000 cycles at 5 and 10 C. The application of COFs to improve SMAs in this work demonstrates a new strategy for improving sodium metal batteries. [ABSTRACT FROM AUTHOR]

Rationally tuning the emission position and narrowing the full width at half‐maximum (FWHM) of an emitter is of great importance for many applications. By synergistically improving rigidity, strengthening the resonant strength, inhibiting molecular bending and rocking, and destabilizing the HOMO energy level, a deep‐blue emitter (CZ2CO) with a peak wavelength of 440 nm and an ultranarrow spectral FWHM of 16 nm (0.10 eV) was developed via intramolecular cyclization in a carbonyl/N resonant core (QAO). The dominant υ0‐0 transition character of CZ2CO gives a Commission Internationale de I'Éclairage coordinates (CIE) of (0.144, 0.042), nicely complying with the BT.2020 standard. Moreover, a hyper‐fluorescent device based on CZ2CO shows a high maximum external quantum efficiency (EQEmax) of 25.6 % and maintains an EQE of 22.4 % at a practical brightness of 1000 cd m−2. [ABSTRACT FROM AUTHOR]

Rationally tuning the emission position and narrowing the full width at half‐maximum (FWHM) of an emitter is of great importance for many applications. By synergistically improving rigidity, strengthening the resonant strength, inhibiting molecular bending and rocking, and destabilizing the HOMO energy level, a deep‐blue emitter (CZ2CO) with a peak wavelength of 440 nm and an ultranarrow spectral FWHM of 16 nm (0.10 eV) was developed via intramolecular cyclization in a carbonyl/N resonant core (QAO). The dominant υ0‐0 transition character of CZ2CO gives a Commission Internationale de I'Éclairage coordinates (CIE) of (0.144, 0.042), nicely complying with the BT.2020 standard. Moreover, a hyper‐fluorescent device based on CZ2CO shows a high maximum external quantum efficiency (EQEmax) of 25.6 % and maintains an EQE of 22.4 % at a practical brightness of 1000 cd m−2. [ABSTRACT FROM AUTHOR]

The development of photoinduced luminescent radicals with dynamic emission color is still challenging. Herein we report a novel molecular radical system (TBIQ) that shows photo‐controllable luminescence, leading to a wide range of ratiometric color changes via light excitation. The conjugated skeleton of TBIQ is decorated with steric‐demanding tertiary butyl groups that enable appropriate intermolecular interaction to make dynamic intermolecular coupling possible for controllable behaviors. We reveal that the helicenic pseudo‐planar conformation of TBIQ experiences a planarization process after light excitation, leading to more compactly stacked supermolecules and thus generating radicals via intermolecular charge transfer. The photo‐controllable luminescent radical system is employed for a high‐level information encryption application. This study may offer unique insight into molecular dynamic motion for optical manufacturing and broaden the scope of smart‐responsive materials for advanced applications. [ABSTRACT FROM AUTHOR]

The development of photoinduced luminescent radicals with dynamic emission color is still challenging. Herein we report a novel molecular radical system (TBIQ) that shows photo‐controllable luminescence, leading to a wide range of ratiometric color changes via light excitation. The conjugated skeleton of TBIQ is decorated with steric‐demanding tertiary butyl groups that enable appropriate intermolecular interaction to make dynamic intermolecular coupling possible for controllable behaviors. We reveal that the helicenic pseudo‐planar conformation of TBIQ experiences a planarization process after light excitation, leading to more compactly stacked supermolecules and thus generating radicals via intermolecular charge transfer. The photo‐controllable luminescent radical system is employed for a high‐level information encryption application. This study may offer unique insight into molecular dynamic motion for optical manufacturing and broaden the scope of smart‐responsive materials for advanced applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • A glutathione responsive photosensitizer (HB−NBD) based on hypocrellin B (HB) was designed. • HB−NBD shows almost no fluorescence and 1O 2 generation due to PET process. • The HB can be released in the presence of GSH, resulting in high phototoxicity to cancer cells. As a typical natural photosensitizer, hypocrellin B (HB) offers the advantages of high molar extinction coefficient, high phototoxicity, low dark toxicity, and fast metabolism in vivo. However, the lack of tumor specificity hinders its clinical applications. Herein, we designed and synthesized a glutathione (GSH) responsive photosensitizer based on HB. The 7 − nitro − 2,1,3 − benzoxadiazole (NBD) covalently connected to HB not only served as a fluorescence quenching group but also as a GSH activating group. The photosensitizer HB−NBD showed almost no fluorescence and singlet oxygen generation as a result of the photoinduced electron transfer between HB and NBD. The designed photosensitizer HB−NBD can be activated by GSH in solutions and cancer cells, and then obtain recuperative fluorescence and photosensitive activity. [ABSTRACT FROM AUTHOR]

Single‐atom catalysts (SACs) have received widespread interest for their high atomic efficiency, enriched active sites, excellent catalytic performance, and low cost. However, the agglomeration of single metal atoms and the use of inactive additives for affixing powdery SACs on planar electrodes may reduce the density of active sites, diminish the charge transport to active sites, and thus suppress their performance. Herein, a series of metal–nitrogen–carbon single‐atom aerogels (M‐SAAs, M: Cu, Ni, Au, Ru) are synthesized via a universal strategy, in which the merits of metal organic frameworks and carbon aerogels are perfectly combined to prevent the agglomeration of single metal atoms and overcome the problem of poor electrical conductivity. The as‐prepared M‐SAAs can be directly employed as self‐supporting electrodes for the electrochemical dechlorination of 1,2‐dichloroethane, and outstanding activity and stability are observed. Significantly, the Cu‐SAA with abundant Cu−N4 sites shows an extraordinarily high ethylene production rate of 446 µmol h−1, with a selectivity of 99% and Faradaic efficiency of 64%. Moreover, theoretical calculations are performed to demonstrate the selectivity and activity of different metal active sites. This study provides a new strategy to exploit highly effective SACs and offers an intensive insight into the mechanism of electrochemical dechlorination reactions. [ABSTRACT FROM AUTHOR]

Multiple resonance (MR) type thermally activated delayed fluorescence (TADF) material is currently a research hotspot in organic light‐emitting diodes (OLEDs) due to their high color purity and high exciton utilization. However, there are only a handful of MR‐TADF emitters with emissions beyond the blue‐to‐green region. The very limited emission colors for MR‐TADF emitters are mainly caused by the fact that so far molecular modifications of MR‐TADF do not offer much change in the emission colors. Here, we report a new approach to modifying a prototypical MR core of DABNA by fusing carbazoles to the MR framework. The carbazole‐fused molecule (TCZ‐F‐DABNA) basically maintains the MR‐dominated features of DABNA while red‐shifting the emission. Its OLED achieves an external quantum efficiency of 39.2 % with a peak at 588 nm, which is a record‐high efficiency for OLEDs with peaks beyond 560 nm. This work provides a new approach for significantly tunning emission colors of MR‐TADF emitters. [ABSTRACT FROM AUTHOR]

Multiple resonance (MR) type thermally activated delayed fluorescence (TADF) material is currently a research hotspot in organic light‐emitting diodes (OLEDs) due to their high color purity and high exciton utilization. However, there are only a handful of MR‐TADF emitters with emissions beyond the blue‐to‐green region. The very limited emission colors for MR‐TADF emitters are mainly caused by the fact that so far molecular modifications of MR‐TADF do not offer much change in the emission colors. Here, we report a new approach to modifying a prototypical MR core of DABNA by fusing carbazoles to the MR framework. The carbazole‐fused molecule (TCZ‐F‐DABNA) basically maintains the MR‐dominated features of DABNA while red‐shifting the emission. Its OLED achieves an external quantum efficiency of 39.2 % with a peak at 588 nm, which is a record‐high efficiency for OLEDs with peaks beyond 560 nm. This work provides a new approach for significantly tunning emission colors of MR‐TADF emitters. [ABSTRACT FROM AUTHOR]

Although the performance of blue perovskite LEDs (PeLEDs) has improved rapidly in the past few years, it still lags behind their green and red counterparts. One major cause of the inferior performance is the relatively low photoluminescence quantum yield (PLQY) of blue perovskite emitters due to more severe nonradiative recombination loss induced by traps and exciton–exciton annihilation (EEA). In this study, theoretical analysis reveals that trap‐induced recombination limits the maximum obtainable PLQY and EEA leads to fast roll‐off at high excitons densities. To address these issues, a synergic approach by introducing CsAc into perovskite and applying solvent annealing (SA) is used to suppress the trap‐induced recombination and the EEA, respectively. The acetate anion in CsAc effectively passivates defects of perovskite through Lewis acid–base reaction, enhancing PLQY of the perovskite films from 10.7% to 49.2%. Furthermore, carrier recombination dynamic investigations reveal that EEA and PLQY roll‐off are successfully deferred with SA treatment. As a result, external quantum efficiency (EQE) is improved from 2.9% to 11% and EQE roll‐off is significantly suppressed at high current density. This work demonstrates that alleviating trap‐induced and EEA non‐radiative losses are two effective methods to improve the PLQY and EQE of blue PeLEDs. [ABSTRACT FROM AUTHOR]

Solar‐driven water vaporization for freshwater production attracts significant interest due to its potential for solving global water scarcity problems. In this review, the recent development of management strategies via diverse rational designs in terms of light, thermal, water, and anti‐salt fouling for enhancement of overall vaporization efficiency, is summarized. For device design, a host–guest concept is raised for clearly elaborating the detailed function and interaction between the solar–thermal material and the substrates. In addition, the rising technologies derived from solar vaporization, such as energy generation, photocatalysis, dehumidification, salt harvesting, sterilization, and biofuel production, are also highlighted. This review provides a new horizon toward the development of solar technologies and practical applications. [ABSTRACT FROM AUTHOR]

Excess PbI2 in perovskite film is an effective strategy for boosting perovskite solar cells (PSCs) performance. However, the presence of unreacted PbI2 is a critical source of intrinsic instability in perovskite under illumination, due to the photolysis of PbI2 (decomposed into metallic lead and iodine). Herein, this issue is solved by applying ionic liquids (ILs) on PSCs where the ILs can form types of stable supramolecules with residual lead iodide. The formation process and mechanism of the supramolecules are elucidated. The residual PbI2 is also revealed to cause high level lead interstitial defects and induced tensile strain which further deteriorate device performance. The self‐assembled supramolecular complex can passivate the PSCs where significant enhancements are achieved in both power conversion efficiency (PCE, from 21.9% to 23.4%) and device stability (retaining 95% of the initial PCE after 4080 h in ambient dry‐air storage, and 80% after 1400 h continuous light illumination). [ABSTRACT FROM AUTHOR]

Herein, two mitochondria-targeting photosensitizers (PSs, CCVJ-Mito-1 and CCVJ-Mito-2) that exhibit a turn-on fluorescence response towards increasing viscosity are reported. Notably, CCVJ-Mito-2 exhibits absorption in the near-infrared (NIR) region, and can be employed as a NIR PS targeting mitochondria and a fluorescent probe for tracking mitochondrial viscosity changes during photodynamic therapy (PDT). This dual functional PS can help to shed light on the dynamic changes of the cellular microenvironment during PDT and further guide the PDT process. [ABSTRACT FROM AUTHOR]

Phase patterning in polymorphic two‐dimensional (2D) materials offers diverse properties that extend beyond what their pristine structures can achieve. If precisely controllable, phase transitions can bring exciting new applications for nanometer‐scale devices and ultra‐large‐scale integrations. Here, the focused electron beam is capable of triggering the phase transition from the semiconducting T" phase to metallic T' and T phases in 2D rhenium disulfide (ReS2) and rhenium diselenide (ReSe2) monolayers, rendering ultra‐precise phase patterning technique even in sub‐nanometer scale is found. Based on knock‐on effects and strain analysis, the phase transition mechanism on the created atomic vacancies and the introduced substantial in‐plane compressive strain in 2D layers are clarified. This in situ high‐resolution scanning transmission electron microscopy (STEM) and in situ electrical characterizations agree well with the density functional theory (DFT) calculation results for the atomic structures, electronic properties, and phase transition mechanisms. Grain boundary engineering and electrical contact engineering in 2D are thus developed based on this patterning technique. The patterning method exhibits great potential in ultra‐precise electron beam lithography as a scalable top‐down manufacturing method for future atomic‐scale devices. [ABSTRACT FROM AUTHOR]