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The architectural design of redox‐active organic molecules and the modulation of their electronic properties significantly influence their application in energy storage systems within aqueous environments. However, these organic molecules often exhibit sluggish reaction kinetics and unsatisfactory utilization of active sites, presenting significant challenges for their practical deployment as electrode materials in aqueous batteries. In this study, we have synthesized a novel organic compound (PTPZ), comprised of a centrally symmetric and fully ladder‐type structure, tailored for aqueous proton storage. This unique configuration imparts the PTPZ molecule with high electron delocalization and enhanced structural stability. As an electrode material, PTPZ demonstrates a substantial proton‐storage capacity of 311.9 mAh g−1, with an active group utilization efficiency of up to 89% facilitated by an 8‐electron transfer process, while maintaining a capacity retention of 92.89% after 8000 charging‐discharging cycles. Furthermore, in‐situ monitoring technologies and various theoretical analyses have pinpointed the associated electrochemical processes of the PTPZ electrode, revealing exceptional redox activity, rapid proton diffusion, and efficient charge transfer. These attributes confer a significant competitive advantage to PTPZ as an anode material for high‐performance proton storage devices. Consequently, this work contributes to the rational design of organic electrode materials for the advancement of rechargeable aqueous batteries. A fully ladder‐type, centrosymmetric organic molecule has been designed and engineered, featuring an optimized electronic configuration, extensive electron delocalization, and robust structural integrity. As an electrode material, it provides an exceptional proton‐storage capacity of 311.9 mAh g−1, characterized by high stability and an active utilization rate of 89%. This performance is enabled by a significant 8‐electron transfer mechanism.

Molecular electronics that can produce functional electronic circuits using a single molecule or molecular ensemble remains an attractive research field because it not only represents an essential step toward realizing ultimate electronic device scaling but may also expand our understanding of the intrinsic quantum transports at the molecular level. Recently, in order to overcome the difficulties inherent in the conventional approach to studying molecular electronics and developing functional device applications, this field has attempted to diversify the electrical characteristics and device architectures using various types of heterogeneous structures in molecular junctions. This review summarizes recent efforts devoted to functional devices with molecular heterostructures. Diverse molecules and materials can be combined and incorporated in such two‐ and three‐terminal heterojunction structures, to achieve desirable electronic functionalities. The heterojunction structures, charge transport mechanisms, and possible strategies for implementing electronic functions using various hetero unit materials are presented sequentially. In addition, the applicability and merits of molecular heterojunction structures, as well as the anticipated challenges associated with their implementation in device applications are discussed and summarized. This review will contribute to a deeper understanding of charge transport through molecular heterojunction, and it may pave the way toward desirable electronic functionalities in molecular electronics applications. The authors present recent advances to develop a wide spectrum of molecular heterostructures, as well as their prospects and applicability. Various molecular heterostructures and their novel electrical characteristics, along with their charge transport mechanisms are presented. In addition, the potential applicability, merits, and perspectives, as well as the anticipated challenges associated with their implementation in electronic device applications are discussed.

Bond dissociation enthalpies (BDEs) of organic molecules play a fundamental role in determining chemical reactivity and selectivity. However, BDE computations at sufficiently high levels of quantum mechanical theory require substantial computing resources. In this paper, we develop a machine learning model capable of accurately predicting BDEs for organic molecules in a fraction of a second. We perform automated density functional theory (DFT) calculations at the M06-2X/def2-TZVP level of theory for 42,577 small organic molecules, resulting in 290,664 BDEs. A graph neural network trained on a subset of these results achieves a mean absolute error of 0.58 kcal mol −1 (vs DFT) for BDEs of unseen molecules. We further demonstrate the model on two applications: first, we rapidly and accurately predict major sites of hydrogen abstraction in the metabolism of drug-like molecules, and second, we determine the dominant molecular fragmentation pathways during soot formation. Bond dissociation enthalpies are key quantities in determining chemical reactivity, their computations with quantum mechanical methods being highly demanding. Here the authors develop a machine learning approach to calculate accurate dissociation enthalpies for organic molecules with sub-second computational cost.

The active layer morphology transition of organic photovoltaics under non-equilibrium conditions are of vital importance in determining the device power conversion efficiency and stability; however, a general and unified picture on this issue has not been well addressed. Using combined in situ and ex situ morphology characterizations, morphological parameters relating to kinetics and thermodynamics of morphology evolution are extracted and studied in model systems under thermal annealing. The coupling and competition of crystallization and demixing are found to be critical in morphology evolution, phase purification and interfacial orientation. A unified model summarizing different phase diagrams and all possible kinetic routes is proposed. The current observations address the fundamental issues underlying the formation of the complex multi-length scale morphology in bulk heterojunction blends and provide useful morphology optimization guidelines for processing devices with higher efficiency and stability. Designing efficient blue perovskite LEDs by using mixed halides perovskite is still a challenge, limited mainly by the phase segregation issue. Here, the authors demonstrate in situ fabrication of quasi-2D CsPbClBr2 nanocrystal films with mixed ligands to overcome the constraint.

Small organic molecules (SOMs) with fascinating chiroptical properties have received much attention for their potential applications in photoelectric and biological devices. As an important research tool, circularly polarized luminescence (CPL) provides information about the chiral structures of these molecules in their excited state, and has been an active area of research. With the development of the commercially available CPL instrumentation, currently, more and more research groups have attempted to enhance the CPL parameters (i.e., quantum yield and dissymmetry factor) of the chiral SOMs from all aspects. This review summarizes the latest five years progresses in research on the experimental techniques and theoretical calculations of CPL emitted from SOMs, as well as forecasting its trend of development.

Hybridizing single‐walled carbon nanotubes (SWCNTs) with π‐conjugated organic small molecules (π‐OSMs) offers a promising approach for producing high‐performance thermoelectric (TE) materials through the facile optimization of the molecular geometry and energy levels of π‐OSMs. Designing a twisted molecular structure for the π‐OSM with the highest occupied molecular orbital energy level comparable to the valence band of SWCNTs enables effective energy filtering between the two materials. The SWCNTs/twisted π‐OSM hybrid exhibits a high Seebeck coefficient of 110.4 ± 2.6 µV K−1, leading to a significantly improved power factor of 2,136 µW m−1 K−2, which is 2.6 times higher than that of SWCNTs. Moreover, a maximum figure of merit over 0.13 at room temperature is achieved via the efficient TE transport of the SWCNTs/twisted π‐OSM hybrid. The study highlights the promising potential of optimizing molecular engineering of π‐OSMs for hybridization with SWCNTs to create next‐generation, efficient TE materials. The SWCNTs/π‐conjugated organic small molecule (π‐OSM) hybrid containing a twisted π‐OSM with reduced barrier energy greatly enhanced carrier transport and thermoelectric (TE)properties by maximizing energy filtering (Seebeck coefficient of 113 µV K−1). The SWCNTs/twisted π‐OSM achieved the best power factor of 2136 µW m−1 K−2 and a maximum ZT of 0.137 at room temperature among carbon nanotube‐based organic TEs.

Proton-conducting materials are essential to the emerging hydrogen economy. Covalent triazine frameworks (CTFs) are promising proton-conducting materials at high temperatures but need more effective sites to strengthen interaction for proton carriers. However, their construction and design in a concise condition are still challenges. Herein, we show a low temperature approach to synthesize CTFs via a direct cyclotrimerization of aromatic aldehyde using ammonium iodide as facile nitrogen source. Among the CTFs, the perfluorinated CTF (CTF-TF) was successfully synthesized with much lower temperature ( ≤ 160 °C) and open-air atmosphere. Due to the additional hydrogen-bonding interaction between fluorine atoms and proton carriers (H 3 PO 4 ), the CTF-TF achieves a proton conductivity of 1.82 × 10 −1  S cm −1 at 150 °C after H 3 PO 4 loading. Moreover, the CTF-TF can be readily integrated into mixed matrix membranes, displaying high proton conduction abilities and good mechanical strength. This work provides an alternative strategy for rational design of proton conducting media. Perfluorinated covalent triazine frameworks are promising proton-conducting materials with high content of phosphoric acid anchor sites to enhance proton conductivity but their synthesis is challenging. Here, the authors report a mild method to produce perfluorinated covalent triazine frameworks displaying high proton conductivity.

Perovskite solar cells have made significant strides in recent years. However, there are still challenges in terms of photoelectric conversion efficiency and long-term stability associated with perovskite solar cells. The presence of defects in perovskite materials is one of the important influencing factors leading to subpar film quality. Adopting additives to passivate defects within perovskite materials is an effective approach. Therefore, we first discuss the types of defects that occur in perovskite materials and the mechanisms of their effect on performance. Then, several types of additives used in perovskite solar cells are discussed, including ionic compounds, organic molecules, polymers, etc. This review provides guidance for the future development of more sustainable and effective additives to improve the performance of solar cells.

We develop a quantum mechanical formalism to treat the strong coupling between an electromagnetic mode and a vibrational excitation of an ensemble of organic molecules. By employing a Bloch-Redfield-Wangsness approach, we show that the influence of dephasing-type interactions, i.e., elastic collisions with a background bath of phonons, critically depends on the nature of the bath modes. In particular, for long-range phonons corresponding to a common bath, the dynamics of the 'bright state' (the collective superposition of molecular vibrations coupling to the cavity mode) is effectively decoupled from other system eigenstates. For the case of independent baths (or short-range phonons), incoherent energy transfer occurs between the bright state and the uncoupled dark states. However, these processes are suppressed when the Rabi splitting is larger than the frequency range of the bath modes, as achieved in a recent experiment (Shalabney et al 2015 Nat. Commun. 6 5981). In both cases, the dynamics can thus be described through a single collective oscillator coupled to a photonic mode, making this system an ideal candidate to explore cavity optomechanics at room temperature.

Organic molecules with tailorable chemical structures, high stability, and solution processability have great potential in the sensing field. Compared with p‐type organic small molecules (OSMs), the electron‐dominated n‐type analogs show superior conductivity when exposed to reducing gases, which can achieve outstanding sensor signal‐to‐noise ratios. However, inadequate humidity resistance at room temperature hinders the development of such molecules. Herein, an A‐D‐π‐D‐A molecular design strategy is proposed based on electron‐deficient B←N units, which results in effective intramolecular charge transport and sensitive responses by extending the π‐conjugation bridge. As a result, the ST‐2BP with A‐D‐π‐D‐A configuration shows a prominent sensitivity of 787 (Ra/Rg) in 20 ppm NH3 at room temperature and an almost initial and stable response under different relative humidity conditions, which is the highest among currently reported OSM sensors. Supported by theoretical calculations and in situ FTIR spectra, it is revealed that B←N units, which function as the active centers mediate the specific ammonia adsorption. This study provides a new understanding of the design of high‐performance room temperature gas sensing materials by decorating B←N units. An extended A‐D‐π‐D‐A molecular design strategy is reported to regulate the energy level and bandgap of organic small molecules NH3 sensing materials by introducing stable boron dipyrromethene and π‐extended stilbene. The extended A‐D‐π‐D‐A type ST‐2BP organic small molecule with low lowest unoccupied molecular orbital (LUMO) energy and high electron cloud density exhibits a high specificity response to NH3, with the electron‐deficient B←N units as active sites.