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The influence of multi‐step sintering at high temperatures was used to meticulously characterize the crystallization, mechanical, and optical properties of a SiO2−Li2O−Al2O3−K2O−P2O5${\rm SiO}_2{-}{\rm Li}_2{\rm O}{-}{\rm Al}_2{\rm O}_3{-}{\rm K}_2{\rm O}{-}{\rm P}_2{\rm O}_5$ glass system with the addition of ZrO2${\rm ZrO}_2$ and Y2${\rm Y}_2$O3${\rm O}_3$. The research began with a novel base glass composition of 3.8 wt% Li2${\rm Li}_2$CO3${\rm CO}_3$, 4.2 wt% K2${\rm K}_2$CO3${\rm CO}_3$, 4.5 wt% Al2${\rm Al}_2$O3${\rm O}_3$, 35 wt% SiO2${\rm SiO}_2$, and 2.5 wt% (NH4)2${({\rm NH}_4)}_2$HPO4${\rm HPO}_4$, to which 47 wt% ZrO2${\rm ZrO}_2$ and 3 wt% Y2${\rm Y}_2$O3${\rm O}_3$ added. The initial glass powder was sintered in two steps at low temperatures. Either 500∘C$^\circ{\rm C}$ for 10 min or 500∘C$^\circ{\rm C}$ for 10 min then a raise to 650∘C$^\circ{\rm C}$ for 20 min was used in the first step. Then, the second step of sintering was done at 850∘C$^\circ{\rm C}$. Finally, after the pellet preparation, final calcination was conducted at 1450∘C$^\circ{\rm C}$. The resulting microstructure was a composite material with various grain components embedded within a glass matrix. The low first sintering temperature triggered the optimum crystal growth, and after the final calcination process, a new glass‐ceramic named ZrSiO4−ZrO2−Zr0.95Y0.066O1.985${\rm ZrSiO}_4{-}{\rm ZrO}_2{-}{\rm Zr}_{0.95}{\rm Y}_{0.066}{\rm O}_{1.985}$–LiAl(SiO3)2${\rm LiAl}{({\rm SiO}_3)}_2$ was synthesized. The synthesized ceramics demonstrated strong diametral tensile strength and excellent Vickers micro‐hardness values, a remarkable refractive index, and optical band gaps larger than 3.1 eV. Consequently, the process of multi‐step sintering at high temperatures clenches the impending manufacture of a novel composite ceramic having remarkable hardness and good optical properties that encourage several biological, technological, and industrial applications. [ABSTRACT FROM AUTHOR]

We investigate the comprehensive analysis's structural, electronic, optical, and elastic properties of Cs₂NaScX₆ (X = Cl, Br) double perovskites using density functional theory (DFT) implemented by the WIEN2k code. The results show that both compounds are in cubic phases. The calculated tolerance factors show both are stable compounds. The computed optimized lattice parameters are Cs₂NaScX₆ (X = Cl, Br) are 10.72 Å and 12.01 Å, respectively. Employing a modified Becke–Johnson (mBJ) potential electronic nature shows that both compounds are in semiconductor nature, that is, 3.138 eV and 3.977 eV. The calculated elastic constant and perimeters show the Cs₂NaScX₆ (X = Cl, Br) are mechanical stables and also ductile and anisotropic nature. The optical properties described the range of photon energies from 0 to 10 eV, revealing pronounced absorption within the visible spectrum, highlighting their considerable promise for transformative innovations in photovoltaic technology. These double perovskites exhibit superior absorption characteristics compared to their Cs₂NaScX₆ (X = Cl, Br) analogues, thus laying the groundwork for significant advancements in solar energy conversion and photovoltaic applications. [ABSTRACT FROM AUTHOR]

Electronic and vibrational relaxation processes can be optimized and tuned by introducing alternative pathways that channel excess energy more efficiently. An ensemble of interacting molecular systems can help overcome the bottlenecks caused by large energy gaps between intermediate excited states involved in the relaxation process. By employing this strategy, catenanes composed of mechanically interlocked carbon nanostructures show great promise as new materials for achieving higher efficiencies in electronic devices. Herein, we perform nonadiabatic excited state molecular dynamics on different all‐benzene catenanes. We observe that catenanes experience faster relaxations than individual units. Coupled catenanes present overlapping energy manifolds that include several electronic excited states spatially localized on the different moieties, increasing the density of states that ultimately improve the efficiency in the energy relaxation. This result suggests the use of catenanes as a viable strategy for tuning the internal conversion rates in a quest for their utilization for new optoelectronic applications. [ABSTRACT FROM AUTHOR]

Dye‐sensitized down‐conversion nanoparticles (DCNPs) can significantly enhance photon absorption, bridging the gap of narrow and weak absorption cross‐section of lanthanide (Ln) ions, thus fundamentally prompting their near‐infrared (NIR) emission. However, the ideal strategy for utilization of both the singlet and triplet energy of the dyes is hindered by the nanostructures and the dependence on the heavy atom effect. Herein, thermally activated delayed fluorescence (TADF) dye is utilized with a small singlet‐triplet energy gap as the absorption antenna, achieving a 733 fold emission enhancement. This strategy facilitates efficient intersystem crossing (ISC) and reverse intersystem crossing (RISC) processes, enabling effective energy transfer from singlet (S1) and triplet (T1) excitons to emitted energy levels of Er3+. Combining highly Erbium‐doped nanoparticles, the water‐dispersed AD‐sensitized system shows excellent hydrodynamic stability and photostability. This innovative approach marks the first report of TADF dye‐sensitized Ln nanosystems, offering a new direction for photo conversion technology. [ABSTRACT FROM AUTHOR]

The strategy of partial Pb2+ substitution is applied, in prototypical MAPbI3 perovskite, with a large array of metal cations in order to comprehensively explore their possible incorporation in the perovskite lattice at Pb2+ sites and thus obtain improved photostability of the absorber. An analysis of lattice parameters and optoelectronic properties of MAPb1‐xMxI∼3 compositions allowed authors to deduce which metal cations are partially incorporated in the perovskite structure and which are expelled in the form of secondary phases. Curious effects of metal incorporation are observed, such as a decrease in the tetragonal distortion ratio and a change in the band gap. This work reveals that the doping of 11 metal cations significantly improves the photostability of the MAPbI3 films. Multiple MAPb1‐xMxI∼3 formulations deliver superior power conversion efficiencies (PCEs) in solar cells. The DFT calculations further demonstrate a complex relationship between the synthetic conditions and doping patterns. The performed study is thus a stepping stone in the development of more stable perovskite absorbers with superior photovoltaic properties. [ABSTRACT FROM AUTHOR]

Strain engineering is a powerful technique for controlling the performance of semiconductor ceramic systems. In this article, the effect of strain engineering, specifically biaxial compressive and tensile strains, on the bonding characteristics, structure, electronic, and optical properties of nonplanar phosphorene‐like (NPP) ZnS ceramic nanolayers was investigated using density functional theory. It was observed that this ceramic exhibits greater stability under significant tensile strains. The structural stability of NPP‐ZnS ceramic, both with and without biaxial strain, was confirmed by its negative formation energy. Biaxial strain strongly influences the electronic band structure of NPP‐ZnS ceramic nanolayers, leading to a transformation from a direct band gap to an indirect gap under tensile strain. Additionally, the bandgap decreases under compressive strain, while it slightly increases under tensile strain. Various optical properties, including refractive index, extinction coefficient, absorption, reflectivity, optical conductivity, and optical susceptibility, were calculated. Biaxial compressive and tensile strains alter the optical properties, shifting them to higher or lower frequencies. NPP‐ZnS ceramic nanolayers exhibit high optical absorption in the UV range, which can be further enhanced by biaxial strain. Furthermore, under increasing compressive strain, the absorption edge moves toward higher energies. This improvement in optical absorption expands the potential applications of NPP‐ZnS ceramic nanolayers in optoelectronic devices. [ABSTRACT FROM AUTHOR]

Dye‐sensitized solar cell (DSSC) is a potential low‐cost solar energy conversion device that is simple to fabricate with low cost than traditional silicon‐based solar cells. The development of DSSC is hampered by the limitations of using ZnO‐based photoanodes for a number of reasons (e.g., charge recombination, efficiency and expensive method). Photoanode material is one of the crucial components in DSSC, which plays a vital role in overall device performance, and the improvement of photoanode materials is needed. This work is focused to improve the overall performance of DSSCs with reducing problem by incorporating a dopant into ZnO semiconductor material as photoanode. Pristine and silver‐doped zinc oxide (Ag‐ZnO) photoanodes with various weight percentages of Ag (2, 3 and 4 wt%) were prepared by a facile, cost‐effective and quick green‐modified–solvothermal method with diethylamine (precipitating agent) and fig leaf extract (capping agent). The structural, crystalline nature, morphological and optical properties of prepared nanomaterials were analysed using X‐ray diffraction (XRD), field emission scanning electron microscopy (FE‐SEM) and UV–Vis spectrophotometry. The results revealed that the crystallite size of pristine and Ag‐ZnO with 2, 3 and 4 wt% of Ag decreased from 85 to 21 nm by increasing the percentage of Ag. The surface roughness decreased with increasing the weight percentage of Ag, and there is no big change in their morphology. The energy band gaps (Eg) of pristine and Ag‐ZnO with 2%, 3% and 4% Ag determined by Tauc plot were 2.55, 3.05, 3.09 and 3.17 eV, respectively. Among the pristine and Ag‐doped ZnO fabricated devices, the photovoltaic measurements of 4% Ag‐ZnO exhibited superior performance reaching the highest efficiency of 2.25% with a short‐circuit current density (JSC) of ~5.8 mA/cm2, an open‐circuit voltage (VOC) of ~810 mV and a fill factor (FF) of ~0.54, which might be due to large optical band gap, better conductivity, reduced recombination rate and enhanced dye adsorption. [ABSTRACT FROM AUTHOR]

MIL‐53(Fe) is a novel photocatalytic material that has been developed over the past decade; however, significant efforts are still required to fully optimize its photocatalytic performance in order to meet the requirements of practical applications. In this paper, we investigated the effects of size and crystallinity on the photocatalytic performance of MIL‐53(Fe) and its composites x‐MIL‐53(Fe)/g‐C3N4 (x‐MIL‐Fe/CN). During the hydrothermal synthesis process, the control over particle size was achieved by adjusting the amount of acetic acid (HAc). Ball milling was utilized to manipulate both the size and crystallinity of MIL‐53(Fe). Photocatalytic experiments demonstrated that MIL‐53(Fe) and 15‐MIL‐Fe/CN, characterized by the smallest particle sizes and great crystallinity, exhibited the highest photocatalytic activity. This enhancement in photocatalytic activity can be attributed to the reduced band gap and lower recombination rate of photogenerated carriers. Notably, the hydrogen evolution rate for 15‐MIL‐Fe/CN reached up to 4950 μmol·g−1·h−1, but MIL‐53(Fe) achieved a 98% degradation of methyl orange within 60 min. [ABSTRACT FROM AUTHOR]

Organometallic Ru(II)–arene complexes have emerged as potential chemotherapeutic agents for improved cancer treatment. However, the application of Ru(II)–arene complexes as photosensitizers has been rarely explored. In consideration of their excellent biological performance, herein, three Ru(II)–arene complexes 1–3 bearing 2,3,8,9,14,15‐hexamethyl‐5,6,11,12,17,18‐hexaazatrinapthalene (HATN‐Me6) as acceptor ligand have been designed and investigated as potential photosensitizers. Distinctively, complexes 1–3 produced negligible singlet oxygen (1O2) generation in DMF. The mechanism investigations indicated that the large change in equilibrium displacement between the excited and ground states rather than narrow energy gap results in the increased vibrational wave function overlap and non‐radiative decay rate. Remarkably, complexes 1–3 induced greatly enhanced 1O2 generation efficiency in an aggregated state due to the suppression of the non‐radiative decay process, implying that the electronic structures of excited states play an essential role in the photochemical properties and functions of the organometallic Ru(II)–arene complexes. The biological evaluation showed that complexes 1–3 exhibited potent photocytotoxicity against cancer cells, highlighting that organometallic Ru(II)–arene scaffolds are potential platforms for the fabrication of efficient photosensitizers. [ABSTRACT FROM AUTHOR]

Novel three metal complexes were synthesized starting from the selenated Schiff base 2‐(((4‐(benzylselanyl)phenyl)imino)methyl)‐5‐nitrophenol (BnSeOH) ligand. Elements, spectral data, magnetic moment, molar conductance, and thermal gravimetric investigations were used to confirm their structures, as well as X‐ray diffraction, IR, NMR, and MS spectroscopic techniques. Octahedral geometry was proposed for the Fe (III), Cu (II), and Zn (II) complexes. The anticancer and antimicrobial activities were assessed against various mammalian cells and pathogenic strains. Within this context, the Fe (III) complex and BnSeOH ligand were the most cytotoxic, and their toxicity was more pronounced in the case of HepG2 cells. Likewise, the Fe (III) complex and BnSeOH ligand showed good antimicrobial activity against Candida Albicans, Bacillus subtilis, and Pseudomonas aeruginosa pathogens. Furthermore, the antioxidant properties were also estimated using DPPH and SOD bioassays. Computational analysis revealed the ligand exhibits lower reactivity relative to its metal complexes based on the ΔE gap and η values representing energy gap and hardness. The parameters examined in this study provide valuable insight into the bonding, electronic properties, reactivity, and polarity of the compounds under investigation. The pharmacological and computational findings point to promising activities of complexes. [ABSTRACT FROM AUTHOR]

In recent years, researchers have devoted considerable effort to the study of high crystalline titanium‐oxo clusters (TOCs), because TOCs are considered to be the molecular analogs of TiO2 nanoparticles and have the potential to be utilized as effective cleaning and catalytic materials. Two new tartrate‐anchored tetranuclear TOCs functionalized with chromophore ligand of p‐nitrobenzoate (NB)/p‐toluenesulfonate (TS), namely, [Ti4(TA)(NB)2(OiPr)10] (1, H4TA = tartaric acid) and [Ti4(TA)(TS)2(OiPr)10] (2), were synthesized and their structures were characterized by various methods. The molecular structure analyses indicated that 1 and 2 are all tetranuclear {Ti4} TOCs, in which tartrate appears as a hexadentate μ4‐bridging ligand while p‐nitrobenzoate/p‐toluenesulfonate acts as a bidentate μ2‐bridging ligand. TOCs 1 and 2 are of good thermal and solvent stability. Furthermore, their photocurrent responses and photocatalytic degradation activities towards methylene blue (MB) were also investigated. In the presence of H2O2, the photocatalytic degradation efficiencies of MB by 1 and 2 are about 84.43% and 71.00%, respectively, at room temperature under visible light irradiation for 60 min. These findings shed light on designing efficient polycarboxylate‐based TOCs photocatalysts. [ABSTRACT FROM AUTHOR]

A mono‐salamo‐type ligand H2L was prepared to utilize 3‐methoxysalicylaldehyde and a semi‐salamo‐type compound, and its novel trinuclear Ni(II) cluster with two significantly various configurations in the solid state was obtained by reaction of H2L with Ni(II) ions. The trinuclear structure of the Ni(II) cluster was validated by x‐ray technique, and Ni(II) ions exhibited hexa‐coordinated twisted octahedrons. Its structural formula is [Ni3(L)2(μ2‐Cl)2(EtOH)2]. Chloride ions have also successfully double bridged to participate in coordination, and play a critical impact in the trinuclear configuration's stability and charge balance. Two solvent ethanol molecules are also participated in coordination. The coordination ratio of the ligand to the metal ion was verified to be 2:3 by UV–Vis absorption titration spectroscopy. The HOMO and LUMO energies of the frontline molecular orbitals of H2L and the complex were analyzed by DFT calculations, and the energy gap value of the ligand H2L was 4.29 eV, and that of the complex was 0.72 eV. The ligand combined with the metal decreased the energy gap value and produced a more active complex. Furthermore, Hirshfeld surface analysis visualizes the weak interactions of crystalline molecules, and these abundant weak interactions play an especially critical effect in the supramolecular structural self‐assembling. The fluorescent researches proclaimed that the fluorescence intensity of the cluster significantly decreased compared with the ligand, suggesting that this ligand and complex have greater promise for fluorescence sensing. [ABSTRACT FROM AUTHOR]

Antiferroelectric (AFE) has emerged as a promising branch of electroactive materials, due to intriguing physical attributes stemming from the electric field‐induced antipolar‐to‐polar phase transformation. However, the requirement of extremely high electric field strength to switch adjacent sublattice polarization poses great challenges for exploiting new molecular AFE system. Although photoirradiation is striking as a noncontact and nondestructive manipulation tool to optimize physical properties, optical control of antiferroelectricity still remains unexplored. Here, by adopting light‐sensitive I3− anion into 2D perovskite family, we design a new I3−‐intercalated molecular AFE of (t‐ACH)2EA2Pb3I10(I3)0.5 ⋅ ((H3O)(H2O))0.5 (1, t‐ACH=trans‐4‐aminomethyl‐1‐cyclohexanecarboxylate, EA=ethylammonium). The I3−‐intercalating gives an ultra‐narrow band gap of 1.65 eV with strong absorption. In term of AFE structure, the anti‐parallel alignment of electric dipoles results in a large spontaneous polarization of 4.3 μC/cm2. Strikingly, 1 merely shows AFE behaviour in the dark even under ultrahigh voltage, while the field‐induced ferroelectric state can be facilely obtained upon visible illumination. Such unprecedented visible‐photo‐assisted phase switching ascribes to the incorporation of photoactive I3− anions that reduces AFE‐to‐ferroelectric switching barrier. This pioneering work on the photo‐assisting transformation of ferroic orders paves a way to develop future photoactive materials with potential applications. [ABSTRACT FROM AUTHOR]

Developing efficient scintillators with environmentally friendly compositions, adaptable band gaps, and robust chemical stability is crucial for modern X‐ray radiography. While copper(I)‐iodide cluster crystals show promise, the vast design space of inorganic cores and organic ligands poses challenges for conventional approaches. In this study, we present machine learning‐guided discovery of copper(I)‐iodide cluster scintillators for efficient X‐ray luminescence imaging. Our findings reveal that combining base learning models with fused features enhances model generalization, achieving an impressive determination coefficient of 0.88. By leveraging this approach, we obtain a high‐performance Cu(I)‐I cluster scintillator, named copper iodide‐(1‐Butyl‐1,4‐diazabicyclo[2.2.2]octan‐1‐ium)2, which exhibit radioluminescence 56 times stronger than that of PbWO4, and enables a detection limit for X‐rays of 19.6 nGyair s−1. Furthermore, we demonstrate the versatility of these scintillators by incorporating them as microfillers in the fabrication of flexible composite scintillators for X‐ray imaging, achieving a static resolution of 20 lp mm−1 and demonstrating promising performance for dynamic X‐ray imaging. [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]

The lanthanide contraction involves a reduction in atomic radius among f‐block elements below the expected level. A similar contraction is observed in group‐16 elements. The atomic radius of Se (117 pm) is slightly larger than that of S (104 pm) arising from the presence of d electrons, compared to the significant increase in atomic radius from O (73 pm) to S. This lanthanide‐like contraction contributes to Se's robust oxidative resistance. Here we report a selective oxidation strategy utilizing Se's strong antioxidative property to remove coexisting narrow‐band gap Te impurities from Se feedstocks. This strategy selectively oxidizes volatile Te impurities into involatile TeO2 that remains in the evaporation source, while only volatile Se deposits onto the substrate during the thermal‐evaporation deposition process. This enables the fabrication of high‐purity Se films possessing a wide band gap of 1.88 eV, ideally suited to the optimal band gap for indoor photovoltaics (IPVs). The resulting Se photovoltaics exhibit an efficiency of 20.1 % under 1000‐lux indoor illumination, outperforming market‐dominant amorphous silicon and all types of lead‐free perovskite IPVs. Unencapsulated Se devices show no efficiency degradation after 20,000 hours of storage in ambient atmosphere. [ABSTRACT FROM AUTHOR]

Organic red/near‐infrared (NIR) room temperature phosphorescence (RTP) materials with low toxicity and facile synthesis are highly sought after, particularly for applications in biotechnology and encryption. However, achieving efficient red/NIR RTP emitters has been challenging due to the weak spin‐orbit coupling of organics and the rapid nonradiative decay imposed by the energy gap law. Here we demonstrate highly efficient red/NIR RTP with boosted quantum yields (Φps) of up to 32.96 % through doping the thionated derivatives of phthalimide (PAI) (MTPAI and DTPAI) into PAI crystals. The red‐shifted photoluminescence (PL) stems from a combination of the external heavy atom effect and the formation of emissive clusters centered around electron‐rich sulfur atoms. Furthermore, the dopants enhance exciton generation efficiency and facilitate energy transfer from smaller PAI units to larger aggregates, leading to dramatically increased Φp. This strategy proves universal, opening possibilities for acquiring long‐wavelength RTP with tunable photophysical properties. The doped crystals exhibit promising applications in optical waveguides and encryption paper/ink. This research provides a practical approach to obtaining long‐wavelength RTP materials and offers valuable insights into the mechanisms governing host‐guest systems. [ABSTRACT FROM AUTHOR]

BiFeO3 (BFO) thin films are well‐known for their multiferroic and photovoltaic properties, driving extensive research into potential applications. Highly ordered pyrolytic graphite (HOPG) substrates, with a graphene‐like surface structure, provide an ideal platform for assessing the impact of graphene electrodes. This study investigates the photovoltaic properties of ITO/BFO/HOPG devices with La‐doped BFO thin films at concentrations of 5, 10, and 15 mol%. The polycrystalline BFO thin films exhibited a preferential (111) orientation, with the 10 mol% La‐doped thin films demonstrating optimal crystallinity and the highest remanent polarization of 50.8 µC/cm2. Photovoltaically, the 5 mol% La‐doped BFO thin film exhibited an open‐circuit voltage (Voc) of 0.46 V and the highest short‐circuit current (Jsc) of 0.38 mA/cm2. The 10 mol% La‐doped BFO thin film achieved the highest Voc of 0.57 V with a Jsc of 0.35 mA/cm2, likely because of enhanced ferroelectric polarization. In contrast, the 15 mol% La‐doped BFO thin film showed a reduced band gap but diminished photovoltaic performance. The minimal variation in the band gap (within 0.1 eV) suggests that the improved photovoltaic performance is primarily driven by increased polarization resulting from enhanced tetragonality. [ABSTRACT FROM AUTHOR]

Herein, a series of fluorinated quinoxaline core–based chromophores (MTH1‐MTH6) with A1–π–A2–π–A1 configuration was designed by structural modulation of end‐capped acceptors in MTHR. The quantum chemical calculations were accomplished at MPW1PW91/6‐311G(d,p) functional to explore optoelectronic and photovoltaic properties of these designed compounds. The findings revealed that all the derivatives exhibited narrow band gap (Egap = 2.163–2.666 eV) with red shift spectra (610.24–766.944 eV in chloroform) as compared with MTHR. The designed compounds exhibited comparable open‐circuit voltage (Voc) and higher power conversion efficiencies (PCEs) as compared with the MTHR. Among the entitled chromophores, MTH1 was found to be a promising chromophore for organic solar cells (OSCs) owning to its lowest Egap (2.163 eV) with highest absorption peak (766.944 nm in chloroform and 717.709 nm in gaseous phase). The aforementioned findings indicate that molecular engineering of chromophores with extended acceptors enhances photovoltaic response, and this motivates researchers to develop highly effective photovoltaic devices. [ABSTRACT FROM AUTHOR]

Eggshell (ES)‐based photocatalysts have gained attention in recent years. They are less toxic, abundant, affordable, and efficient photocatalysts in treating dye‐polluted water. This work reports the deterioration of Congo red (CR) under visible light region using ES‐integrated graphitic carbon nitride (g‐C3N4). The photocatalyst was prepared by thermal condensation by varying the mass ratios of ES powder. The material structure and the morphological characteristics are confirmed using FTIR, XRD, BET, UV‐DRS, UV‐Vis spectra, SEM, EDAX, and photoluminescence. By optical investigations, the band gap of bare ES was found to have a value of 5.04 eV. It was narrowed down to 2.57 eV at the optimum composition of ES/g‐C3N4. The effects of several reaction parameters, such as the initial concentration of dye, the amount of catalyst, and the pH level of the solution on the photodegradation rate were investigated. The degradation results revealed that the catalyst removed around 90.5% of the CR dye in 90 min at 498 nm when subjected to visible light. A pseudo‐first‐order model was concluded from the kinetic data analysis of the mineralization of CR dye using carbon nitride photocatalysts infused with eggshells. The photodegradation rate of 5% ES g‐C3N4 was three times greater than that of pure g‐C3N4, indicating a decreased recombination rate of the electron‐hole pair. [ABSTRACT FROM AUTHOR]

The poor conductivity of β‐Ga2O3 limits its application in optoelectronic devices. Currently, there have been advancements in investigating the impact of Mo doping on the photoelectric characteristics of β‐Ga2O3. However, there are few studies on the impact of different valence states of Mo doping and the coexistence of O vacancy and interstitial H on the electrical properties of β‐Ga2O3. In the process of preparing β‐Ga2O3, O vacancy and interstitial H inevitably exist. In response to these problems, the first‐principles GGA + U method is used to study the impact of different valence states of Mo doping and the coexistence of interstitial H and O vacancy on the electrical properties of β‐Ga2O3. The electronic structure, mobility, conductivity, and carrier lifetime of the system are calculated and analyzed. The results show that all doping systems are more stable under Ga‐rich conditions. The band gap of the Mo‐doped β‐Ga2O3 system gradually narrows, which is mainly attributed to the Burstein–Moss effect and the multiplicity reintegration effect. Mo doping effectively improves the electrical conductivity of the system. Ga47O72Mo16+H11+ system has the longest carrier lifetime; Ga47O72Mo16+H10 has the largest mobility; Ga47O72Mo15+H10 system has the highest conductivity. Therefore, Mo‐doped β‐Ga2O3 materials help to prepare new electrical performance devices. [ABSTRACT FROM AUTHOR]

The poor conductivity of β‐Ga2O3 limits its application in optoelectronic devices. Currently, there have been advancements in investigating the impact of Mo doping on the photoelectric characteristics of β‐Ga2O3. However, there are few studies on the impact of different valence states of Mo doping and the coexistence of O vacancy and interstitial H on the electrical properties of β‐Ga2O3. In the process of preparing β‐Ga2O3, O vacancy and interstitial H inevitably exist. In response to these problems, the first‐principles GGA + U method is used to study the impact of different valence states of Mo doping and the coexistence of interstitial H and O vacancy on the electrical properties of β‐Ga2O3. The electronic structure, mobility, conductivity, and carrier lifetime of the system are calculated and analyzed. The results show that all doping systems are more stable under Ga‐rich conditions. The band gap of the Mo‐doped β‐Ga2O3 system gradually narrows, which is mainly attributed to the Burstein–Moss effect and the multiplicity reintegration effect. Mo doping effectively improves the electrical conductivity of the system. Ga47O72Mo16+H11+ system has the longest carrier lifetime; Ga47O72Mo16+H10 has the largest mobility; Ga47O72Mo15+H10 system has the highest conductivity. Therefore, Mo‐doped β‐Ga2O3 materials help to prepare new electrical performance devices. [ABSTRACT FROM AUTHOR]

In this study, bilayer MoS2 was synthesized on graphene film using chemical vapor deposition (CVD) to get a hetero‐film photo‐catalyst for the photo‐assisted charging of Li‐oxygen battery. The synthesized hetero‐film exhibited an optical band gap of 1.8 eV and a valence band edge potential of −1.23 VAg/AgCl (2.04 VLi+/Li). Fast‐responding photocurrents in the microampere range were achieved through on‐off cycles under visible‐light irradiation. The anodic nature of the photocurrents indicated that the synthesized semiconductor film was n‐type. Photo‐assisted testing demonstrated that the MoS2/graphene hetero‐film photo‐catalyst significantly reduced the charging potential and increased the discharging potential at a current density of 0.1 mA cm−2, thereby greatly enhancing the cyclic performance of the Li‐oxygen battery. [ABSTRACT FROM AUTHOR]

Experimental investigations of silica under high pressure and temperature offer crucial insights into modeling of Earth and super‐Earths' interiors. Despite extensive studies on Hugoniots of silica polymorphs like fused‐silica (2.20 g/cm3), quartz (2.65 g/cm3) and stishovite (4.29 g/cm3) up to a terapascal, unexplored region of melting and liquid of silica at high pressures is leaved because of the Hugoniots dependence on ambient density. This emphasizes the urgence to supplement the phase diagram to constrain silica properties under extreme conditions. Here, the Hugoniot and shock temperature of coesite (2.92 g/cm3) were studied by laser shock compression experiments up to 950 GPa. Our findings confirm shock‐induced superheating in coesite, revealing a higher Grüneisen parameter and lower electrical conductivity compared to those of fused‐silica and quartz along an isothermal line (<2 × 104 K). These results suggest unique properties of shocked coesite, which imply a warmer and longer‐lived silica magma ocean of earlier rocky‐planets. Plain Language Summary: Silica is a critical mineral in Earth's interior. Studying its behavior under extreme conditions offers essential insights into planetary processes, enhancing our understanding of Earth and other rocky worlds in our solar system and beyond. In our research, we focused on a particular form of silica called coesite, compressing it to extraordinarily high pressures ‐ up to 950 GPa by using the GEKKO laser's powerful laser drive. Our experiments uncovered unique properties of silica in its liquid state, such as a high Grüneisen parameter and electrical conductivity after melting, indicating potential support for dynamo processes despite retaining semi‐metallic traits. Our findings suggest that magma oceans could have formed earlier and endured longer than previously assumed, where the high Grüneisen parameter accelerates temperature rises during planetary formation processes like accretion or giant impacts. Existence of a conducting mantle of SiO2‐bearing liquid could result in complex magnetic fields on such planets, posing challenges for detecting and modeling exoplanetary magnetic fields. This research significantly advances planetary science, deepening our grasp of planetary evolution and the diverse processes shaping rocky worlds across the cosmos. Key Points: Shocked coesite exhibits superheating before melting, suggesting incomplete crystallization under rapid compressionGrüneisen parameter estimated by coesite‐quartz Hugoniot reveals higher γ, affecting thermodynamic models of rocky planetsHigh conductivity of shocked coesite after melting indicates band gap closure, with a persistent pseudo‐gap in the liquid phase [ABSTRACT FROM AUTHOR]

ABSTRACT Using pyrimidinethione, a new series of pyridinyl‐pyrimidine candidates was prepared by reacting with diverse carbon‐centered electrophiles like hydrazonoyl chloride, N‐arylchloroacetamide, ethyl chloroacetate, and enaminone derivatives. Some heteroannulated compounds, such as triazolopyrimidine and thiazolopyrimidine derivatives were obtained. The mass fragmentation pathways were investigated by the electron impact mass spectrometry (EI‐MS), and the molecular ion peaks (M+.) were recorded at different intensities. The in vitro antiproliferative efficacy of the prepared compounds against MCF7 and HCT116 cancer cell lines showed the highest potency of pyrimidinethione 2, triazolopyrimidine 4, and thiazolopyrimidine 10. Also, in silico studies were performed to recognize these findings. A molecular docking simulation towards the EGFR enzyme showed the best docking score of thiazolopyrimidine 10 through H‐bonding and hydrophobic interactions in comparison to the interactions of co‐crystallized ligand and doxorubicin. With DFT calculations, compound 10 exhibited the lowest energy gap and the highest softness. Among ADME simulation, compounds 7, 8, 9, and 11 exhibited desirable lead‐likeness. It is hoped that this work may affect advancing new effective antiproliferative agents. [ABSTRACT FROM AUTHOR]

Thermally activated delayed fluorescence (TADF) emitters have garnered much attention due to 100% exciton utilization and toxic metal‐free design but often experience concentration‐quenching, requiring dispersion into the host matrix. Developing emitters that maintain consistent performance and emission wavelength irrespective of the concentration remains a significant challenge. Herein, two TADF emitters (2BPy‐pTC and 2BPy‐oTC) are designed and synthesized. The nature and energetics of the lowest excited singlet (S1) and triplet (T1) along with the extent of through‐bond exciton transfer (TBET) and through‐space exciton transfer (TSET) are unveiled using reliable quantum‐chemical calculations. While 2BPy‐pTC exhibits pre‐dominantly TBET, a greater extent of TSET is found in 2BPy‐oTC. Both emitters show a low singlet‐triplet energy gap (ΔEST), 0.21 eV for 2BPy‐pTC and 0.02 eV for 2BPy‐oTC. For 2BPy‐pTC, increasing the emitter concentration from 5 to 100 wt.% causes a bathochromic shift in the electroluminescence (EL) peak (467 to 495 nm) and a drop in maximum external quantum efficiency (EQEmax) from 12.0% to 5.5%. In contrast, 2BPy‐oTC maintains EL maxima of 500 nm and consistent EQEmax (24.0% – 27.2%) while increasing emitter concentration, acting as a universal emitter for both doped and non‐doped OLEDs and eliminating the need for tedious co‐deposition. [ABSTRACT FROM AUTHOR]

A comprehensive study of excitonic properties of 2D layered perovskites is provided, with an emphasis on understanding and controlling the exciton fine structure. First, an overview of the optical properties is presented, discussing the challenges in determining the bandgap and exciton binding energies. Through magneto‐optical spectroscopic measurements (up to B = 140 T), scaling laws are established for exciton binding energy as a function of the band gap and the diamagnetic coefficient. Using an in‐plane magnetic field, the exciton fine structure for various 2D perovskites is examined to measure the energy splitting between the excitonic levels. The exciton fine structure and exchange interaction are correlated with structural parameters, employing an effective mass model, to highlight the role of steric effect on the exchange interaction. These findings reveal that lattice distortions, introduced by organic spacers, significantly influence the exchange interaction, driving a tunable energy spacing between dark and bright excitons. This unique feature of 2D perovskites, not present in other semiconductors, offers a novel tuning mechanism for exciton control, making these materials highly promising for efficient light emitters and advanced quantum technologies. [ABSTRACT FROM AUTHOR]

Disorder‐induced electronic localization is responsible for the OFF state of the Ovonic threshold switching (OTS) device, which is an indispensable component in the present 3D‐crossbar‐architecture phase‐change memory circuit. However, the atomic mechanism of the OTS device, especially the role of thermal effect, remains a long‐term open question. Recent researches suggest that the working current of the OTS ON‐state is often large enough to melt the adjacent phase‐change memory material in the OTS+PCM devices. Thus, Joule heating‐induced atomic/electronic structure transition in OTS materials must be seriously considered. Taking the typical OTS material GeSe as an example, first‐principles calculations reveal an unexpected electronic delocalization induced by the enhanced structural disorder upon solid‐liquid transition. Meanwhile, as the temperature rises, the band gap decreases or even closes, leading to an increase in carrier concentration. Therefore, the melting filament with high conductivity could be responsible for the holding‐ON state of OTS materials. The results in this study may provide possible explanations for some puzzles of OTS devices, such as the reasons for holding‐ON state and limited endurance. [ABSTRACT FROM AUTHOR]

The topic of wastewater remediation has been extensively discussed in recent years, and one of the main pollutants has been dyes. One of the promising techniques for dye degradation is photocatalysis. A novel transition metal Fe with different percentage (15%, 20%, 25%) doped Co3O4 was prepared employing a novel green process using Mangifera Indica leaf extract.The structural, morphological, optical, and electrical properties of doped catalyst was studied by XRD, FTIR, FE‐SEM, HR‐TEM, PL, CV, EIS, TGA, XPS, UV‐DRS, and BET analysis.By doping the Fe metal on the surface of Co3O4 resulting increase in surface area with improving charge carriers separation and lower the band gap energy. The photocatalytic activity was studied by degrading BG dye under solar light.25% Fe doped cobalt oxide having band gap energy 2.1 eV showed maximum degradation efficiency of 96% at pH 8 on 30 ppm dye concentration with 30 mg catalyst under 90min.The radical trapping experiment showed the vital role of hydroxyl and superoxide radical in degradation mechanism. By doping Fe atoms the efficiency of the host is increased which will be the most promising candidate for the photocatalytic dye degradation applications. The material presents a strong possibility for use in super capacitor applications due to its increased current density and lower on set potential. [ABSTRACT FROM AUTHOR]

Cyclopenta‐annulated polycyclic aromatic hydrocarbons (CP‐PAHs) are of significant interest due to their unique optoelectronic properties and applications in organic electronic devices. Phenanthroacephenanthrylene (PAP) isomers are CP‐PAHs that have been rarely investigated, and only the [9,10‐e]PAP isomer was explored to date. Herein, we report the syntheses, crystal structure and optoelectronic properties of two PAP isomers, 7‐ethoxy[2,1‐e]PAP 1 and 9‐ethoxy[1,2‐e]PAP 2. The structural isomers were synthesized in multi‐steps, and structural elucidations were performed using NMR, mass, and single‐crystal X‐ray diffraction analyses, revealing planar backbone of the isomers. UV‐visible absorption and fluorescence spectra of compound 1 were red‐shifted than that of 2, suggesting smaller HOMO–LUMO energy gap which is further validated by DFT calculations that suggested the lowering of HOMO–LUMO spacing could be attributed to the greater destabilization of HOMO for 1. [ABSTRACT FROM AUTHOR]

The properties of the active layer materials play a decisive role in determining the power conversion efficiency of organic solar cells (OSCs). Chlorophyll and its derivatives are abundant and environmentally friendly functional organic molecular materials. Using density functional theory (DFT) and time‐dependent density functional theory (TD‐DFT), we have calculated the absorption spectra and their excited state properties based on optimized ground state structures. It was found that bacteriochlorin exhibits superior structural properties, a smaller energy gap and hole reorganization energy, redshifted absorption spectra, and higher hole mobility compared to the donor D18. This suggests that bacteriochlorin exhibits superior donor properties. Comparative studies between o‐AT‐2Cl and m‐AT‐2Cl showed that o‐AT‐2Cl had superior acceptor properties, implying that differences in substitution positions can influence the physicochemical properties of non‐fullerene acceptors (NFAs). Subsequently, six bulk heterojunctions (BHJs) were constructed by combining three donors with nonfused ring electron acceptors, o‐AT‐2Cl and m‐AT‐2Cl. The bacteriochlorin‐based BHJs performed well among them, with BChl3/o‐AT‐2Cl and BChl4/o‐AT‐2Cl having the largest interfacial charge separation rate. The results suggested that BHJs composed of bacteriochlorin and NFAs can improve OSCs' photovoltaic performance, providing a feasible scheme for designing efficient OSCs. [ABSTRACT FROM AUTHOR]

Advanced control of light focusing, reflection, and transmission is possible with highly refractive transparent materials; however, such materials are difficult to discover because of the negative correlation between the refractive index and the optical band gap. This study elucidates half‐Heuslers as highly refractive transparent materials, considering their densely packed crystal structures comprising both covalent and ionic bonds with d orbitals. Theoretical calculations revealed that 22 ternary half‐Heusler systems (αβγ) exhibited higher refractive indices with wider band gaps than conventional high‐refractive‐index‐transparent materials in the near‐infrared region. The key to achieving a high index and wide gap is aligning α‐d and β‐d levels within a small lattice frame given by small γ elements to the verge of forming Γ‐point conduction band minimum. Experimental examinations revealed that α and γ elements with low and high melting points are preferred for the thin‐film preparation of the well‐ordered half‐Heuslers. Highly refractive transparent half‐Heuslers and their material designs expedite post‐silicon technology for controlling near‐infrared light. [ABSTRACT FROM AUTHOR]

Embedding donor–acceptor type thermally activated delayed fluorescence (TADF) molecules in a rigid surrounding lead to structural inhomogeneity, and deteriorating emission decay rates. Designing TADF structures with hampered rotational flexibility between donor and acceptor structural units is shown to lower the conformational disorder. However, in this work, it is shown that it is not always enough. In fact, the negative impact of conformational inhomogeneity may be reduced by lowering the singlet‐triplet energy gap (ΔEST) and boosting the reverse intersystem crossing (rISC) rate while preserving the same donor‐acceptor orientation. In such cases the lower ΔEST enables the early triplet upconversion even from the conformers with unfavorably low D‐A twist angles, which is not observed in compounds with larger ΔEST. In this way, the temporal shifts of prompt and delayed fluorescence are evidently reduced. When the reverse intersystem crossing is inactive at low temperatures, nearly the same fluorescence peak shifts are observed, as expected for compounds with similar molecular geometry. In this way, low ΔEST and rapid rISC are shown to be of fundamental importance not only for TADF efficiency but also for the temporal dynamics in the solid‐state. [ABSTRACT FROM AUTHOR]

This work describes a new synthetic route for the production of a low‐cost and environmentally friendly catalyst: a zinc oxide‐based system doped with silver, prepared using a novel sol–gel method with cassava starch to form the gel. The photocatalysts were characterized by different techniques: X‐ray diffraction (XRD), X‐ray fluorescence spectroscopy (XRF), energy dispersive X‐ray spectroscopy (EDS), transmission electron microscopy (TEM), photoacoustic spectroscopy (PAS), and point of zero charge (PZC). The XRF and EDS results indicated that photocatalysts doped with 2%, 5%, 8%, and 10%, silver could be obtained successfully. The synthesis method employed produced nanoparticles of ~30 nm, as confirmed by XRD and TEM results. The band gap energy values of the materials (ranging from 1.98 to 3.05 eV) fall within the range suitable for catalyst activation under UV radiation. Photocatalytic reactions were carried out with two emerging pollutants, 2,4‐d‐dichlorophenoxyacetic acid (2,4D) and caffeine, to verify the catalytic activity of the synthesized catalyst. The results indicated that the catalyst was efficient for the degradation of both pollutants. Tests using solar radiation led to 100% degradation of 2,4D. Cl− ions did not influence the process negatively. The amount of caffeine removed by the photocatalytic process used in solar radiation was ~97% due to the low band gap energy values of the synthesized material. [ABSTRACT FROM AUTHOR]

The ternary potassium sulfido and selenido ferrates K9[Fe2S(e)7] were synthesized as pure phases through a facile and straightforward solid‐state method. The compounds crystalize isotypic as has been reported previously. UV‐visible measurements indicate semiconductivity, showing direct optical band gaps with energies of 1.91 eV for the sulfido and 1.72 eV for the selenido ferrate. Investigations of dielectric and impedance properties provide their dielectric constants in the range of 60 to 74 at room temperature at a frequency of 1 kHz, as well as ionic conductivity values in the range of 2.08 ⋅ 10−5 and 2.61 ⋅ 10−5 mS cm−1. Both, the dielectric constants and the calculated ionic conductivity of the selenido ferrate are higher compared to the sulfido ferrate, corresponding to the larger unit cell volume and increased bond lengths in the selenido ferrates. The dielectric constants are comparably higher than the reference material of SiO2, which might introduce them for dielectric applications. [ABSTRACT FROM AUTHOR]

PIBs are emerging as a promising energy storage system due to high abundance of potassium resources and theoretical energy density, however, progress of PIBs is severely hindered by structural instability and poor cycling of anode material during continual insertion and extraction of larger‐sized K+. Hence, developing anode material with structural stability and stable cycling remains a great challenge. Herein, band gap‐tuned Mo‐doped and carbon‐coated lead titanate (CMPTO) with zero‐strain K+ storage is presented as ultra‐stable PIBs anode. Mo doping introduces narrowed band gap and optimized crystal lattice for enhanced intrinsic electron and ion transfer. Demonstrated by in situ XRD characterizations, the crystal structure stays stable with unchanged peak positions, fully revealing zero‐strain characteristic of CMPTO anode during potassium storage for stable cyclic capability. Ultimately, CMPTO anode achieved ultra‐stable cycling performance of 7000 cycles at 500 mA g−1 with high capacity retention of 90 % and considerable specific capacity of 130.9 mAh g−1 after 600 cycles at 100 mA g−1; with relatively large density, CMPTO realized eminent volumetric capacity of 1111.09 mAh cm−3 and ultra‐long cycling life of 10000 cycles at 7041 mA cm−3. This work introduces a promisingly new route into developing anode materials with ultra‐stable performance for PIBs. [ABSTRACT FROM AUTHOR]

Inverted perovskite/organic tandem solar cells (P/O TSCs) suffer from poor long‐term device stability due to halide segregation in organic–inorganic hybrid wide‐band gap (WBG) perovskites, which hinders their practical deployment. Therefore, developing all‐inorganic WBG perovskites for incorporation into P/O TSCs is a promising strategy because of their superior stability under continuous illumination. However, these inorganic WBG perovskites also face some critical issues, including rapid crystallization, phase instability, and large energy loss, etc. To tackle these issues, two multifunctional additives based on 9,10‐anthraquinone‐2‐sulfonic acid (AQS) are developed to regulate the perovskite crystallization by mediating the intermediate phases and suppress the halide segregation through the redox‐shuttle effect. By coupling with organic cations having the desirable functional groups and dipole moments, these additives can effectively passivate the defects and adjust the alignment of interface energy levels. Consequently, a record Voc approaching 1.3 V with high power conversion efficiency (PCE) of 18.59 % could be achieved in a 1.78 eV band gap single‐junction inverted all‐inorganic PSC. More importantly, the P/O TSC derived from this cell demonstrates a T90 lifetime of 1000 h under continuous operation, presenting the most stable P/O TSCs reported so far. [ABSTRACT FROM AUTHOR]

Purely organic molecules exhibiting near‐infrared (NIR) emission possess considerable potential for applications in both biological and optoelectronic technological domains, owing to their inherent advantages such as cost‐effectiveness, biocompatibility, and facile chemical modifiability. However, the repertoire of such molecules with emission peaks exceeding 750 nm and concurrently demonstrating high photoluminescence quantum efficiency (PLQE) remains relatively scarce due to the energy gap law. Herein, we report two open‐shell NIR radical emitters, denoted as DMNA‐Cz‐BTM and DMNA‐PyID‐BTM, achieved through the strategic integration of a donor group (DMNA) onto the Cz‐BTM and PyID‐BTM frameworks, respectively. We found that the donor‐acceptor molecular structure allows the two designed radical emitters to exhibit a charge‐transfer excited state and spatially separated electron and hole levels with non‐bonding characteristics. Thus, the high‐frequency vibrations are effectively suppressed. Besides, the reduction of low‐frequency vibrations is observed. Collectively, the non‐radiative decay channel is significantly suppressed, leading to exceptional NIR PLQE values. Specifically, DMNA‐Cz‐BTM manifests an emission peak at 758 nm alongside a PLQE of 55 %, whereas DMNA‐PyID‐BTM exhibits an emission peak at 778 nm with a PLQE of 66 %. Notably, these represent the pinnacle of PLQE among metal‐free organic NIR emitters with emission peaks surpassing 750 nm. [ABSTRACT FROM AUTHOR]

Quinone compounds, with the ability to uptake protons, are promising electrodes for aqueous batteries. However, their applications are limited by the mediocre working potential range and inferior rate performance. Herein, we examined quinones bearing different substituents, and for the first time introduce tetraamino‐1,4‐benzoquinone (TABQ) as anode material for proton batteries. The strong electron‐donating amino groups can effectively narrow the band gap and lower the redox potentials of quinone materials. The protonation of amino groups and the amorphization of structure result in the formation of an intermolecular hydrogen‐bond network, supporting Grotthuss‐type proton conduction in the electrode with a low activation energy of 192.7 meV. The energy storage mechanism revealed by operando FT‐IR and ex situ XPS features a reversible quinone‐hydroquinone conversion during cycling. TABQ demonstrates a remarkable specific capacity of 307 mAh g−1 at 1 A g−1, which is one of the highest among organic proton electrodes. An all‐organic proton battery of TABQ//TCBQ has also been developed, achieving exceptional stability of 3500 cycles at room temperature and excellent performance at sub‐zero temperature. [ABSTRACT FROM AUTHOR]

The discovery of triangular‐shaped molecules displaying an inverted singlet–triplet (INVEST) energy gap between their lowest singlet (S1) and triplet (T1) states opened the way for a new strategy to increase the internal quantum efficiency (IQE) of organic light‐emitting diodes (OLEDs), enhancing the reverse intersystem crossing (RISC) thanks to a downhill process. However, the compounds showing a negative ΔEST suffer from both a vanishing spin–orbit coupling (SOC) between these excited states and high energy differences with higher‐lying singlets and triplets, therefore limiting their involvement in the spin conversion process. Here, we proposed a new design strategy entailing the extension of the triangulene cores by connecting two INVEST triangulene units to form Uthrene‐ and Zethrene‐like systems, doped with N and B. The inspection of the resulting molecular orbitals (MOs) distribution allowed rationalizing the electronic structure properties obtained from wavefunction‐based methods, showing how the Uthrene‐like architecture can lead to the quasi‐resonance between S1 and T1, in some cases provoking their inversion. By feeding a kinetic model with the non‐radiative rate constants, calculated from first principles, we showed how the extended INVEST (X−INVEST) design strategy can open new pathways to boost the spin conversion process and the population of the emissive S1. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) are promising for high‐efficiency tandem applications, but their long‐term stability, particularly due to ion migration, remains a challenge. Despite progress in stabilizing PSCs, they still fall short compared to mature technologies like silicon. This study explores how different piperazinium salt treatments using iodide, chloride, tosylate, and bistriflimide anions affect the energetics, carrier dynamics, and stability of 1.68 eV bandgap PSCs. Chloride‐based treatments achieved the highest power conversion efficiency (21.5%) and open‐circuit voltage (1.28 V), correlating with stronger band bending and n‐type character at the surface. At the same time, they showed reduced long‐term stability due to increased ionic losses. Tosylate‐treated devices offered the best balance, retaining 96.4% efficiency after 1000 h (ISOS‐LC‐1I). These findings suggest that targeted surface treatments can enhance both efficiency and stability in PSCs. [ABSTRACT FROM AUTHOR]

Mn doping has been used to improve the physical chemistry of lead halide perovskite nanocrystals such as CsPbX3, where X is a halogen ion. In this paper, a two‐phase method for Mn‐doped CsPbX3 nanosheets (where X=Br, Cl), namely water‐hexane system, is reported. Compared to conventional catalyst arrays, the band gap of CsPbBr3 nanocrystalline is easily tuned, the carrier diffusion distance is remote, the band edge position of the band structure is favorable for a wide range of electrocatalytic redox reactions, and the catalytic active site is maximally exposed, providing a larger electrolyte contact area. The porous hierarchical structure also accelerates the release of hydrogen bubbles. The results showed that the optimized Mn : CsPbBr3 catalyst exhibited excellent electrolytic performance of aquatic hydrogen in alkaline electrolyte (1 mol/L KOH). The overpotentials of the oxygen evolution reaction (OER) at the current densities of 10 and 100 mA cm−2 are only 114.4 and 505.4 mV, respectively, with a Tafel slope of 43 mV dec−1. At a current density of 10 mA cm−2, the excess potential required for the hydrogen evolution reaction (HER) is 158.6 mV and it exhibits excellent electrochemical stability. The Mn : CsPbBr3 nanocrystalline consists of two electrodes for hydrolysis of water, requiring only a voltage of 1.45 V. This provides implications for the optimization of electrocatalysts in alkaline electrolytes with the aim of developing next generation 2D electrocatalysts for overall water splitting. [ABSTRACT FROM AUTHOR]

The inherent defects (lead iodide inversion and iodine vacancy) in perovskites cause non‐radiative recombination and there is also ion migration, decreasing the efficiency and stability of perovskite devices. Eliminating these inherent defects is critical for achieving high‐efficiency perovskite solar cells. Herein, an organic molecule with multiple active sites (4,7‐bromo‐5,6‐fluoro‐2,1,3‐phenylpropyl thiadiazole, M4) is introduced to modify the upper interface of perovskites. When M4 interacts with the perovskite surface, the active bromine (Br) site interacts with lead (Pb) at the surface to repair iodine atomic vacancy defects. The fluorine (F) site of M4 interacts with Pb to correct octahedral crystal lattice distortions and eliminate PbI defects. Additionally, sulfur–iodine (S–I) interactions reduce I–I dimerization and eliminate IPb defects. It is also calculated that the energy level of M4 aligns with the band gap, promoting charge transfer. As a result, the perovskite devices achieve an efficiency of 25.1%, a stabilized power output (SPO) of 25.0%, a voltage of 1.19 V, and a fill factor of 85.2%. The device retains 95% of its initial efficiency after 2000 h of ageing in a nitrogen atmosphere. Thus, multi‐point cooperative passivation of surface defects provides an effective method to improve the efficiency and stability of perovskite solar cells. [ABSTRACT FROM AUTHOR]

Limited by the energy gap law, purely organic materials with efficient near‐infrared room temperature phosphorescence are rare and difficult to achieve. Additionally, the exciton transition process among different emitting species in host–guest phosphorescent materials remains elusive, presenting a significant academic challenge. Herein, using a modular nonbonding orbital‐π bridge‐nonbonding orbital (n‐π‐n) molecular design strategy, we develop a series of heavy atom‐free phosphors. Systematic modification of the π‐conjugated cores enables the construction of a library with tunable near‐infrared phosphorescence from 655 to 710 nm. These phosphors exhibit excellent performance under ambient conditions when dispersed into a 4‐bromobenzophenone host matrix, achieving an extended lifetime of 11.25 ms and a maximum phosphorescence efficiency of 4.2 %. Notably, by eliminating the interference from host phosphorescence, the exciton transition process in hybrid materials can be visualized under various excitation conditions. Spectroscopic analysis reveals that the improved phosphorescent performance of the guest originates from the triplet‐triplet energy transfer of abundant triplet excitons generated independently by the host, rather than from enhanced intersystem crossing efficiency between the guest singlet state and the host triplet state. The findings provide in‐depth insights into constructing novel near‐infrared phosphors and exploring emission mechanisms of host–guest materials. [ABSTRACT FROM AUTHOR]

Wide‐bandgap (WBG) perovskite solar cells (PSCs) are crucial component of tandem solar cells (TSCs). However, the main obstacles currently faced by WBG PSCs are their imperfect crystal quality, leading to large open circuit voltage (VOC) losses and poor stability. The use of 2,5‐dibromothieno[3,2‐B] thiophene (DBrT) as an additive in WBG PSCs enhances crystal quality, mitigates defects, and improves stability by promoting crystal growth and passivating bulk and interface defects. The interaction between Pb─S bonds, π–π stacking, and hydrogen bonding facilitates an ordered molecular arrangement, leading to better crystallization and reduced non‐radiative recombination. Meanwhile, DBrT can also spontaneously diffuse to the grain boundary, thus permeate to top and buried surfaces of perovskite, further passivating defects at the interfaces and reducing non‐radiative recombination. This strategy not only improves energy level alignment and carrier transport but also achieves a champion power conversion efficiency (PCE) of 22.40% for the inverted WBG PSC with a high VOC of 1.27 V. a PCE of 20.39% for semi‐transparent devices, and a high 28.31% PCE for 4‐terminal all‐perovskite tandem solar cells, thereby offering a comprehensive approach to enhancing the performance of WBG and tandem perovskites. [ABSTRACT FROM AUTHOR]

As an exceptional optical gene, the [PO4] tetrahedron is indispensable in the field of optical crystals due to its gain in the band gap of solid materials. However, the high symmetry of [PO4] tetrahedron hinders the achievement of large optical anisotropy in the lattice for phosphate crystal forms. In this work, the heteroleptic tetrahedra strategy, which involves replacing some of the oxygen atoms on regular oxy‐tetrahedra, is proven to be a feasible approach for preserving the wide transmission of the original [PO4] tetrahedra and improving the polarizability anisotropy. Based on this, eight methylphosphates are designed and synthesized for the phosphate system by substituting a [CH3] group for the O atom on the [PO4] tetrahedra. Theoretically, as compared to [PO4] units, [CH3PO3] and [CH3PO3H] units can improve the polarizability anisotropy, particularly [CH3PO3H] units, which have the potential to be birefringence‐active. The strong birefringence (exp. 0.108@546.1 nm) and short deep‐UV cutoff edge (195 nm) of nonmetallic methylphosphates [C(NH2)3][CH3PO3H] in the series suggest that it may be a possible short‐wave UV birefringent crystal. In addition to providing new birefringence‐active units for optical material design, this study validates the viability of modifying tetrahedra to improve inherent short board of nearly rigid [PO4] tetrahedra in phosphate family. [ABSTRACT FROM AUTHOR]

Metal thiophosphates (MTPs) are a large family of 2D materials that exhibit large structural and chemical diversity. They also show promise for applications in energy harvesting and photodetection. Strain and defect engineering have previously been demonstrated as useful mechanisms to tune several properties of MTPs such as resistivity, magnetic state, and electronic band gap. However, the effect of these stimuli on engineering tunable light emission in MTPs remains unexplored. Here, it is experimentally demonstrated that sulfur vacancies in metal thiophosphate AgScP2S6${\rm AgScP_{2}S_{6}}$ allow defect‐state‐to‐valence‐band transitions leading to visible light emission at sub‐bandgap energies, while structural defects in the material can enhance and modulate the photoluminescence spectrum. It is also showed that the structural‐defect‐enhanced light emission can be further tuned by temperature‐induced strain gradients. [ABSTRACT FROM AUTHOR]

Artificial photosynthesis, encompassing the photocatalytic generation of H2 and CO2 reduction innovations, seems to be a highly promising approach. This is due to its ability to efficiently transform CO2 into hydrocarbon fuel and valuable chemical products using solar energy as a direct energy source. This will simultaneously help to mitigate global warming and energy shortage issues. Chalcogenide‐based semiconductors have recently gotten a lot of attention as an important area of research for photocatalytic H2 production and CO2 conversion, owing to their low band gap energy, suitable band structures, and a great photoresponsivity spectrum. Modifying chalcogenides into their heterostructures could be a great way to solve problems like photo corrosion and carrier recombination. Therefore, this review summarized a series of different modifications of chalcogenides and recent developments in their photocatalytic and photo electrocatalytic performance, particularly in H2 production and CO2 conversion. Lastly, we discussed the challenges, limitations, areas for development, and future prospects of chalcogenides and their heterostructures capable of utilizing visible light to produce H2 gas and reduce CO2. [ABSTRACT FROM AUTHOR]

High‐spin polycyclic hydrocarbons (PHs) hold significant potential in organic spintronics and organic magnets. However, their synthesis is very challenging due to their extremely high reactivity. Herein, we report the successful synthesis and isolation of a kinetically blocked derivative (1) of dianthraceno[2,3‐a : 3′,2′‐h]‐s‐indacene, which represents a rare persistent triplet diradical of a Kekulé PH. Its triplet ground state was unambiguously confirmed by electron paramagnetic resonance and superconducting quantum interference device measurements. Its structure was also unequivocally confirmed through X‐ray crystallographic analysis, and its electronic properties were systematically investigated by both experiments and theoretical calculations. The key design principle is to extend the π‐conjugation for achieving the decrease of the bonding interaction and the increase of the exchange interaction between unpaired electrons, which are essential for accessing the stable triplet ground state. Due to kinetic blocking, 1 shows a reasonable stability with a half‐life time of 64 h under ambient conditions. It has a narrow HOMO–LUMO energy gap and displays amphoteric redox behavior. Notably, its dication and dianion exhibit a closed‐shell ground state and near‐infrared absorption, and the structures were identified by X‐ray crystallographic analysis. This study will shed new light on the design and synthesis of novel stable PHs with high‐spin multiplicity. [ABSTRACT FROM AUTHOR]

Owing to high theoretical capacitance, nickel cobalt alkaline carbonate (NiCoAC) has attracted wide attention in electrochemical energy storage. However, the high surface ionic resistance and low bulk intrinsic activity result in NiCo‐AC being unable to exhibit fast electronic response frequency and charge storage. Herein, via precisely controlling gradient S‐doping, NiCo‐AC nanowire is in situ converted into core‐shell bimetallic oxysulfide (NiCo─O─S), with interior particularly presenting a granular due to the contraction of bulk structure, achieving the synergistic modification of surface and bulk. Specifically, owing to the lower band gap energy of metal sulfides, the derived shell optimizes OH− adsorption center from Ni to Ni─Co─Ni sites with higher binding energy, and the granular core facilitates further ion diffusion with enhanced charge accumulation. Hence, NiCo─O─S reflect higher redox activity than that of nickel‐cobalt sulfide (NiCo─S) and NiCo‐AC, with an ultrahigh capacitance of 3,298 F g−1 at 1 A g−1. The as‐fabricated supercapacitors display an outstanding energy density of 131 Wh kg−1 at 800 W kg−1 and present high capacitance retention of 98.5% and coulomb efficiency of 93.2％ under 12 000 charge‐discharge cycles. This study reflects a new insight into activating the intrinsic activity of nanomaterials to further develop high‐rate and stable electrodes. [ABSTRACT FROM AUTHOR]