ChemPhotoChem最新文献

A dansyl-appended koneramine ligand (L^DnH) was designed as a photofunctional probe for Cu²⁺ sensing. The ligand and its Zn(II), Cd(II), Cu(II), and Co(II) complexes were synthesized and fully characterized. L^DnH exhibits strong green fluorescence, which was preferentially quenched by Cu²⁺ ions over a wide range of competing cations. Fluorescence titrations established 1:1 stoichiometry and revealed a high Stern–Volmer constant (K_SV = 3.40 × 10⁵ M⁻¹), with a detection limit (LOD = 0.27 μM) well below the US EPA guideline. Importantly, the probe demonstrated excellent reversibility through Cu²⁺/EDTA cycles, enabling reusability. Density functional theory calculations supported the experimental findings by providing insight into the electronic properties and stability of the complex. These findings establish L^DnH as a robust, reusable Cu²⁺ sensor, while demonstrating the potential of koneramine scaffolds in the design of fluorescent probes.

Owing to thermally coupled energy levels (TCLs), Er³⁺-activated phosphors have garnered notable attention for their use in optical thermometry. Herein, Er³⁺-activated Ca₂SrWO₆ was examined for the optical thermometry within 298–523 K. A series of Er³⁺-doped Ca₂SrWO₆ phosphors with varying Er³⁺ concentration were prepared using solid-state reaction with calcine temperature of 1200°C. Under 380 nm excitation, the Ca₂SrWO₆:Er³⁺ displayed strong green photoluminescence (PL) at 527 nm (²H_11/2-⁴I_15/2) and 560 nm (⁴S_3/2-⁴I_15/2). To investigate the thermometric performance, the temperature-dependent PL (TDPL) spectra of the Ca₂SrWO₆:Er³⁺ phosphor were recorded within 298–523 K. Upon 380 nm excitation, the Er³⁺ prominent transitions, ²H_11/2-⁴I_15/2 and ⁴S_3/2-⁴I_15/2, displayed different responses to thermal variation. Taking this into account, the principle of fluorescence intensity ratio (FIR) of the TCLs, the thermometry investigation has conducted. The maximum relative sensitivity (S_R) attained to be 0.69% K⁻¹ at 298 K, indicating the suitability of the phosphor for thermometry. Additionally, repeatability experiments carried out to check the reliability of the FIR confirm the excellent performance in thermometry. Moreover, the decay lifetime of the ⁴S_3/2 state of the Er³⁺ was evaluated from the luminescence decay, and the photometric analysis confirms the green emission of the phosphors with the highest color purity of 92.67%.

The Front Cover illustrates the molecular components and 3D printing approach applied in a new study. Photoinitiators, made up a central diketone unit (highlighted in yellow) in combination with the monomer PETA and the scavenger TEMPO, collectively form the photoresist, while blue laser irradiation enables fabrication of the depicted 3D structure. More information can be found in the Research Article by S. Bräse and co-workers (DOI: 10.1002/cptc.202500337).

The Cover Feature depicts a bidirectional route leading to two different destinations, signifying the two distinct types of S^VI phenanthridines that can be accessed by a new photoredox strategy. The starting materials, biphenyl vinyl azides, are depicted as tourists taking a joyride atop a steam locomotive on a blue moon day. Energy harvesting from blue moonlight by Ru/Ir-based catalysts and the use of SO₂ gas produced from burning coal as fuel in steam locomotives are also depicted as an analogy to our reaction conditions. The tourists choose either the cyclopropanol route, involving HAT, or the thianthrenium salt route, involving SET, to reach the appropriate destination. More information can be found in the Research Article by T. Khan and co-workers (DOI: 10.1002/cptc.202500297). Bhavik Parve is acknowledged for his contribution to the graphic.

Electron donor–acceptor (EDA) complexes have gained prominence for enabling efficient, catalyst-free transformations under mild conditions. On the other hand, hypervalent iodine compounds, known for their low toxicity, environmental compatibility, and versatile oxidative reactivity, have recently emerged as powerful electron acceptors in EDA complexation. Therefore, the integration of these concepts will offer a new route for sustainable, selective, and innovative strategies in modern organic synthesis. This review summarizes the recent advances on the synthetic strategies occurred through EDA complex formation using hypervalent iodine reagent (HIR) with literature coverage up to June, 2025.

Sensitized triplet–triplet annihilation can be utilized to upconvert low-intensity visible (Vis) light into ultraviolet (UV) light, making it useful for applications powered by short-wavelength sunlight. However, dye systems for this wavelength range are limited. Here, we report that Vis-to-UV upconversion (UC) is achieved with dye pairs that include the thermally activated delayed fluorescence (TADF) luminophores 2,3,5,6-tetrakis(carbazol-9-yl)benzonitrile (4CzBN) or 2,4,5,6-tetrakis(9H-carbazol-9-yl) isophthalonitrile (4CzIPN) as sensitizer and bis(phenylethynyl)benzene (BPEB) or an alkoxylated BPEB derivative as emitter. The photophysical characterization of degassed toluene solutions of the four possible combinations of these dyes reveals efficient triplet energy transfer efficiencies exceeding 80%, upconverted UV emission centered at ca. 380 nm with an anti-Stokes shift of up to 0.64 eV from the blue range of the optical spectrum, excitation threshold intensities as low as ca. 25 mW·cm⁻², and UC quantum yields up to 4.5%, depending on the dye combination. These results establish pairs of TADF sensitizers and BPEB emitters as viable candidates for Vis-to-UV (UC), broadening the molecular design space for next-generation photonic and solar-powered UV applications.

The design of industrially relevant synthetic methodologies is expected to aim for circularity—commonly indicated by the upcycling or recycling of reagents/catalysts/solvents and minimizing the waste generated while ensuring complete or stoichiometrically relevant conversions. This demanding set of criteria makes the attainment of circularity very challenging. The present article aims toward achieving near-circularity in the form of a facile photosynthetic strategy utilizing dye-TiO₂ system in water with visible light activation and air oxidation for highly selective amine oxidation. Control experiments provide critical insights in to the role of water when used as a reaction medium. Selective conversion imines, facile yields, recyclability of the catalyst, and demonstrated scalability are all instrumental for achieving circularity. The present article is a proof-of-concept that water can be a critical component for incorporating circularity in the synthetic protocol.

Hydrogen and its applications are very important technologies for our society, and possessing various methods for its production is key to security and economic stability in these sectors. Photoelectrocatalytic water splitting is a unique route for hydrogen generation in that it utilizes resources of abundant water, unlimited sunlight, and readily available materials such as oxynitride semiconductors. Oxynitrides are popular candidates for photoactive material but suffer from degradation in corrosive electrolytes. In the endeavor to mitigate this, we employ crystalline thin film model systems fabricated by pulsed laser deposition to separate phenomena at interfaces from those in bulk. This work demonstrates novel fabrication, thorough characterization, and photoelectrochemical testing of two tantalum-containing oxynitride photoanodes, CaTaO_xN_y (CTON) and MgTa₂O_6-xN_x (MTON), in our specially designed multilayer architecture that involves TiN as a current collector and a NiO_x overlayer as the oxygen evolution catalyst. The two systems show stability for over 4 h at 1.5 V_RHE, and the CTON photoanode possesses larger photoresponse. Subsequently, CTON is used to examine the effect of NiO_x overlayer thickness where it is found 2.5 nm maximizes photocurrent density. These results provide the scientific community with new model systems and demonstrate their use to improve catalysts for water splitting technology.

Using two-step absorption instead of two-photon absorption in 3D laser nanoprinting reduces demands on necessary laser systems but still poses a challenge for chemistry. Photoresists consisting of a photoinitiator and a viscous monomer are hardened through photopolymerization with one or two different laser sources. Until now, the influence of the photoinitiator type on printing behavior has remained unclear, limiting the rational design of new materials. In this study, we demonstrate a direct connection between molecular design and printing performance, providing new insights that guide the targeted development of novel photoinitiators. One essential parameter in designing new photoinitiators is the laser power required to initiate photopolymerization, which varies with molecular size, regioisomeric substitution, and substituent type. Screenings in this and a previous study about two-step absorption show that, thus far, the only applicable molecules for this specific 3D printing technique are 1,2-diketones, primarily benzil derivatives. These compounds are mainly synthesized using a Sonogashira cross-coupling reaction followed by an oxidation of the resulting triple bond. The photoinitiators introduced in this work can be referred to as two-step, one-color systems, allowing 3D structures to be printed using only a single 405 nm laser source.

It remains a significant challenge to develop efficient photocatalytic systems toward specific chemical transformation schemes. Herein, this study involves the development of CdS@ZnIn₂S₄@carbon heterojunctions for photocatalytic evolution of hydrogen peroxide. The dual role of the carbon component as an electron mediator/acceptor is crucial for the enhanced evolution rate of peroxide, whereas the relative population of sp2-hybridized domains is greatly correlated with the photocatalytic performance of the ternary hybrids. Compared with the binary counterpart CdS@ZnIn₂S₄, the optimized ternary hybrid (0.3 wt% carbon) demonstrated a fivefold increase in photocatalytic performance. Scavenging experiments confirm that the dominant mechanistic scheme for peroxide evolution is the concerted two-electron oxygen reduction. Furthermore, establishment of the energy diagram reveals efficient spatial separation of charge carriers via a proposed Z-scheme configuration. This work sheds insightful light on the development of functional photocatalytic systems for enhancing performance in specific chemical transformation schemes.