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Through multiscale modeling, it is predicted that TSSSSI is a potential candidate for NIR-II FLI-guided PDT–PTT therapy.

Acceptors in organic solar cells (OSCs) are of paramount importance. On the basis of the well-known non-fullerene acceptor Y6, six acceptors (Y6-COH, Y6-COOH, Y6-CN, Y6-SO

Sulfinyl radicals (R-SO˙) play important roles in lots of reactions, while the isomer oxathiyl radicals (R-OS˙) and the isomerization between them are rarely observed due to the poor stability of R-OS˙. In this work, the complete active space self-consistent field (CASSCF) and its multi-state second order perturbation (MS-CASPT2) methods were employed to study the photo-induced reaction mechanisms of phenylsulfinyl radical PhSO˙ 1 and its isomer phenoxathiyl radical PhOS˙ 2. Our results show that 1 and 2 have similar singly occupied molecular orbitals in the ground state but different properties in the excited state, which determine their diverse behaviors after irradiation. Radical 1 can generate 2 by light irradiation, but 2 produces isomerization product 3 (2-hydroxyphenylthiyl radical) and ring-opening product 4 (acyclic thioketoketene radical) in two paths

The heteroatoms could play a critical role in improving the hole transport and interfacial charge transfer of triphenylamine-based HTM.

This article investigates the combined impact of fiscal and credit policies on green‐firm investment opportunities using firm‐level panel data of green industries in China. Our empirical results demonstrate that subsidies, tax rebates, and green credit loans have significantly U‐shaped nexuses with green‐firm investment opportunities: Subsidies, tax rebates, and green credit policies generate significant interactions on green‐firm investment opportunities. External financing constraints may weaken the incentive of subsidies, tax rebates, and green credit loans on green‐firm investment opportunities.

The design of active cathode catalysts, with abundant active sites and outstanding catalytic activity for CO2 electroreduction, is important to promote the development of solid oxide electrolysis cells (SOECs). Herein, A-site-deficient perovskite oxide (La0.2Sr0.8)0.9Ti0.5Mn0.4Cu0.1O3-δ (LSTMC) is synthesized and studied as a promising cathode for SOECs. Cu nanoparticles can be rapidly and uniformly in situ-exsolved under reducing conditions. The heterostructure formed by the exsoluted Cu and LSTMC provides abundant active sites for the catalytic conversion of CO2 to CO. Combined with the remarkable oxygen-ion transport capacity of the LSTMC substrate, the specially designed Cu@LSTMC cathode exhibits a dramatically improved electrochemical performance. Furthermore, first-principles calculations proposed a mechanism for the adsorption and activation of CO2 by the heterostructure. Electrochemically, the Cu@LSTMC presents a high current density of 2.82 A cm-2 at 1.8 V and 800 °C, which is about 2.5 times higher than that of LSTM (1.09A cm-2).

Molecular engineering has been demonstrated to be a predominant strategy for augmenting the long-term stability and passivating adverse defects for perovskite solar cells (PSCs). Here, using density functional theory calculations combined with

Sequence-selective recognition of cationic amphipathic peptides by synthetic receptors is significant to biological applications, but it is still a great challenging task. Here we first study the binding characteristics of receptor cucurbit[7]uril (CB[7]) to the smallest aromatic tripeptides X1GG (X1 = tryptophan (W), phenylalanine (F), and tyrosine (Y)) and basic tripeptides X2GG (X2 = arginine (R), lysine (K), and histidine (H)) by molecular dynamics simulations. The study indicates that the sidechains of aromatic X1 residues can be encapsulated into the CB[7] cavity, while the sidechains of basic X2 residues prefer to locate at the CB[7] portal. Based on that, we consider hydrophobic aromatic residues as the N-terminus, the smallest glycine (G) as the 2nd-residue and basic residues as the C-terminus, and design nine tripeptides X1GX2 (X1 = F, Y, W and X2 = H, K, R). We found that there is a great influence of the C-terminal basic residue of X1GX2 on binding with CB[7] due to the introduction of a new binding site between CB[7] and the sidechain of the C-terminal residue. Interestingly, CB[7] can differentiate WGR and WGK with similar structures efficiently because of their eight orders of magnitude difference in the association constant (Ka). Besides, for WGR, YGR, and YGK with a nanomolar binding affinity (Ka > 109 M−1), on reversing the sequence order of the 2nd-residue and 3rd-residue, their Ka reduces by about at least 1000-fold, implying the sequence dependence of CB[7] on recognizing these tripeptides. These results predict the potential applications of CB[7] in recognizing cationic amphipathic peptides.

To achieve the efficient and precise regulation of aggregation-induced emission in supramolecular systems, revealing the role of host–guest interactions in AIEgens is of vital importance. Using the theoretical protocol that combines molecular dynamics simulations and the hybrid quantum mechanics/molecular mechanics calculations, we explored the mechanism of host–guest interaction-induced emission enhancement of amphiphilic guest molecules (AIEgens) as both dispersed monomers and assembled aggregates. We confirmed that the binding pattern of host–guest inclusions between α-cyclodextrin (CD) and three amphiphilic guest molecules is that the interior hydrophobic cavity of CD hosts one phenyl ring of the TPE moiety and part of PEG chain of the guest; simultaneously, the exterior hydrophilic surfaces of CD fasten the PEG chain and adjacent phenyl rings of the TPE moiety of guest molecules by intermolecular hydrogen bonds and O–H⋯π interactions, respectively. The packing density of the assembled aggregates decreases as the CD concentration increases. The analysis of the radiative decay rate constants and the reorganization energy indicate that the monomer emission is enhanced after host–guest complexation; meanwhile, combining host–guest interactions and aggregation effects could further increase the fluorescence efficiency, because both host–guest interactions and the aggregation effect can effectively retard the low-frequency intramolecular phenyl ring rotational motions and CC double bond plane twisting, thus suppressing the nonradiative decay channels. The fluorescence emission spectra are also blue-shifted after complexation. Our theoretical protocol is general and applicable to other AIEgens in the supramolecular field, thus laying a solid foundation for the rational design of advanced AIE materials.

The acceptor in organic solar cells (OSCs) is of paramount importance for achieving a high photovoltaic performance. Based on the well-known non-fullerene acceptor Y6, we designed a set of asymmetric A–D1A′D2–A type new acceptors Y6–C, Y6–N, Y6–O, Y6–Se, and Y6–Si by substituting the two S atoms of one thieno[3,2-b]thiophene unit with C, N, O, Se, and Si atoms, respectively. The electronic, optical, and crystal properties of Y6 and the designed acceptors, as well as the interfacial charge-transfer (CT) mechanisms between the donor PM6 and the investigated acceptors have been systematically studied. It is found that the newly designed asymmetric acceptors possess suitable energy levels and strong interactions with the donor PM6. Importantly, the newly designed acceptors exhibit enhanced light harvesting ability and more CT states with larger oscillator strengths in the 40 lowest excited states. Among the multiple CT mechanisms, the direct excitation of CT states is found to be more favored in the case of PM6/newly designed acceptors than that of PM6/Y6. This work not only offers a set of promising acceptors superior to Y6, but also demonstrates that designing acceptors with asymmetric structure could be an effective strategy to improve the performance of OSCs.

Photocatalytic water splitting to produce hydrogen is a potential means of achieving scalable and economically feasible solar hydrogen production. Two-dimensional (2D) triphosphides are 2D materials with potential applications in photovoltaics and optoelectronics. Here, we theoretically investigated 56 systems in total, including seven monolayer XP3 (X = Al, Ga, Ge, As, In, Sn, and Sb) and their combined vertical and lateral heterostructures. We found that the lateral heterostructure AlP3-GaP3 should be a promising photocatalyst for water splitting, through a quadruple screening process combining free energy calculations. It is fascinating that AlP3-GaP3 ingeniously combines all the desired features for photocatalytic water-splitting reactions, including a nearly direct band gap (1.43 eV), perfect band edge position, high STH efficiency (16.89%), broad light absorption region of sunlight, ultrahigh carrier mobility (20,000 cm2 V-1 s-1), low exciton binding energy (0.33 eV), and excellent stability in a water environment. Moreover, through Gibbs free energy calculations, the active sites and possible reaction pathways of the overall water-splitting reaction by AlP3-GaP3 were also confirmed. Our work offers a strategy for the design and fabrication of novel lateral heterostructures for a high-performance photocatalyst in water-splitting reactions.

The electron-transporting material (ETM) in inverted perovskite solar cells (PSCs) plays important role in reducing hysteresis and realizing simple processing procedures, while the improvement of power conversion efficiency is limited by low electron mobility and weak perovskite/ETM interface interaction. In this work, three new ETMs (HAT-1, HAT-2, and HAT-3) were designed by introducing methoxyphenyl, imide, and naphthalene groups into the hexaazatriphenylene (HAT) skeleton, based on the ETM HATNASOC7 synthesized experimentally [Jen

Organic-inorganic halide perovskite solar cells (PSCs) have attracted much attention due to their rapid increase in power conversion efficiencies (PCEs), and many efforts are devoted to further improving the PCEs. Designing highly efficient hole transport materials (HTMs) for PSCs may be one of the effective ways. Herein we theoretically designed three new HTMs (FDT-N, FDT-O, and FDT-S) by introducing a nitrogen-phenyl group, an oxygen atom, and a sulfur atom into the spiro core of an experimentally synthesized HTM (FDT), respectively. And then we performed quantum chemical calculation to study their application potential. The results show that the devices with FDT-O and FDT-S instead of FDT may have higher open circuit voltages owing to their lower highest occupied molecular orbital (HOMO) energy levels. Moreover, FDT-S exhibits the best hole transport performance among the studied HTMs, which may be due to the significant HOMO-HOMO overlap in the hole hopping path with the largest transfer integral. Furthermore, the results on interface properties indicate that introducing oxygen and sulfur atoms can enhance the MAPbI3 /HTM interface interaction. The present work not only offers two promising HTMs (FDT-O and FDT-S) for PSCs but also provides theoretical help for subsequent research on HTMs.

Intramolecular charge transfer (ICT) is a fundamental process in photochemistry, during which charge flows from a donor (D) to an acceptor (A). In (probably) most dyes, ICT is enhanced upon photoex...