Photochemistry

  • Article
    | Open Access

    Commonly, large π-conjugated systems facilitate low-energy electronic transitions. Here, the authors demonstrate that the relief of excited-state antiaromaticity of the benzene core leads to large Stokes shifts, and allows the construction of emitters covering the entire visible spectrum without the need of extending π-conjugation.

    • Heechan Kim
    • , Woojin Park
    •  & Dongwhan Lee
  • Article
    | Open Access

    The generation of alkyl radicals through deoxygenation of abundant alcohols via photoredox catalysis is of interest. In this study, the authors report a one-pot strategy for visible-light-promoted photoredox coupling of alcohols with electron-deficient alkenes, assisted by carbon disulfide and triphenylphosphine.

    • Hong-Mei Guo
    •  & Xuesong Wu
  • Article
    | Open Access

    Radiationless relaxation is ubiquitous in natural processes and often involves excited states that are difficult to observe. Here the authors, combining X-ray transient absorption spectroscopy and computations, provide insight into the photoinduced dynamics in pyrazine and the involvement of an optically dark 1Au(nπ*) state.

    • Valeriu Scutelnic
    • , Shota Tsuru
    •  & Stephen R. Leone
  • Article
    | Open Access

    Spatiotemporal dynamic of charge carriers is commonly studied with optical or photoconductivity measurements, yet these techniques come with their own limitations. To circumvent these limits, the authors probe the free-carrier diffusion dynamics of microsecond lifetimes via laser-illuminated microwave impedance microscopy.

    • Xuejian Ma
    • , Fei Zhang
    •  & Keji Lai
  • Article
    | Open Access

    Catalytic amide bond-forming methods is important because they could potentially address the existing limitations of classical methods using superstoichiometric activating reagents. Here the authors show an Umpolung amidation reaction of carboxylic acids with nitroarenes and nitroalkanes enabled by FeI2, P(V)/P(III) and photoredox catalysis that avoids the production of byproducts.

    • Yunyun Ning
    • , Shuaishuai Wang
    •  & Jin Xie
  • Article
    | Open Access

    The generation of non-stabilized alkyl radicals from sulfonium salts has been a challenge for several decades. Here, the authors show the treatment of S-(alkyl) thianthrenium salts, which can generate non-stabilized alkyl radicals as key intermediates that enable controlled and selective reactions under mild photoredox conditions.

    • Cheng Chen
    • , Zheng-Jun Wang
    •  & Zhuangzhi Shi
  • Article
    | Open Access

    Controlled actuation is an important aspect of synthetic cellular systems. Here, the authors combine pH responsive DNA origami structures with light triggered proton pump engineered E. coli to trigger a change in pH and control the deformation of giant unilamellar vesicles by simple illumination.

    • Kevin Jahnke
    • , Noah Ritzmann
    •  & Kerstin Göpfrich
  • Article
    | Open Access

    Authors demonstrate Si-based MIS photoanodes using Al thin-film reactions to create localized conduction paths through the insulator and Ni electrodeposition to form metal catalyst islands. These approaches yielded low onset potential, high saturation current density, and excellent stability.

    • Soonil Lee
    • , Li Ji
    •  & Edward T. Yu
  • Article
    | Open Access

    A highly efficient, stable, low-cost and environmentally friendly photocathode is the goal of practical solar hydrogen evolution applications. Here, authors report a Cu3BiS3-based photocathode and Cu3BiS3-BiVO4 tandem cell for unbiased overall solar water splitting with a STH efficiency over 2%.

    • Dingwang Huang
    • , Lintao Li
    •  & Feng Jiang
  • Article
    | Open Access

    The Z-scheme photocatalytic system is promising for producing renewable energy by sunlight, but the optimization of multiple materials is challenging. Here, authors directly map out the photocatalytic activity on a microscopic scale by the clustering analysis for the time-resolved image sequence.

    • Makoto Ebihara
    • , Takeshi Ikeda
    •  & Kenji Katayama
  • Article
    | Open Access

    Femtosecond time-resolved X-ray solution scattering (fs-TRXSS) measurements provide information on the structural dynamics of proteins in solution. Here, the authors present a structure refinement method for the analysis of fs-TRXSS data and use it to characterise the ultrafast structural changes of homodimeric haemoglobin.

    • Yunbeom Lee
    • , Jong Goo Kim
    •  & Hyotcherl Ihee
  • Article
    | Open Access

    Arene-fused siloles have attracted interest due to their promising applications in electronic and optoelectronic devices. Here, the authors report Ir(III)-catalyzed cycloaromatization of ortho-alkynylaryl vinylsilanes with arylsulfonyl azides via α-silyl radical Smiles rearrangement for accessing naphthyl-fused benzosiloles under visible-light photoredox conditions.

    • Fengjuan Chen
    • , Youxiang Shao
    •  & Wei Zeng
  • Article
    | Open Access

    Compounds bearing a carbonyl group, such as aldehydes and ketones, are important industrial chemicals and widespread in pharmaceuticals and natural products. Here, the authors report a strategy for visible-light photoredox-catalyzed umpolung carboxylation of diverse carbonyl compounds with CO2, to generate valuable α-hydroxycarboxylic acids.

    • Guang-Mei Cao
    • , Xin-Long Hu
    •  & Da-Gang Yu
  • Article
    | Open Access

    UV-induced photodamage that likely occurred during the prebiotic synthesis of DNA and RNA is still an untackled issue for their origin on early Earth. Here, the authors show that substitution of 2,6-diaminopurine for adenine enables repair of cyclobutane pyrimidine dimers with high yields, and demonstrate that both 2,6-diaminopurine and adenine nucleosides can be formed under the same prebiotic conditions.

    • Rafał Szabla
    • , Magdalena Zdrowowicz
    •  & Janusz Rak
  • Article
    | Open Access

    3D printing enables customized manufacturing that is difficult to achieve through traditional material processing but 3D printing with high resolution and high speed is challenging to realize. Here, the authors demonstrate that photooxidation of a ketocoumarin photosensitizer can simultaneously deliver high print speed and high print resolution on a common 3D printer.

    • Xiaoyu Zhao
    • , Ye Zhao
    •  & Xiaolin Xie
  • Article
    | Open Access

    Three-body dissociation of water, producing one oxygen and two hydrogen atoms, has been difficult to investigate due to the lack of intense vacuum ultraviolet sources. Here, using a tunable free-electron laser, the authors obtain quantum yields for this channel showing that it is a possible route to prebiotic oxygen formation in interstellar environments.

    • Yao Chang
    • , Yong Yu
    •  & Xueming Yang
  • Article
    | Open Access

    The direct and selective C(sp3)-H functionalization of cycloalkanes and alkanes is useful in organic synthesis but its application to asymmetric catalysis has been less explored. Here, the authors demonstrate the incorporation of a dual asymmetric photocatalyst which leads to the development of asymmetric sulfonylation involving direct functionalization of cycloalkanes, alkanes, toluene derivatives or ethers.

    • Shi Cao
    • , Wei Hong
    •  & Lei Gong
  • Article
    | Open Access

    Metabolites can distinguish pathogenic from healthy cells, but they are hard to couple to current photosensitizers without altering their biological activity. Here the authors design a new family of photosensitizers that retain metabolite function to target pathogenic cells and ablate them by photodynamic therapy.

    • Sam Benson
    • , Fabio de Moliner
    •  & Marc Vendrell
  • Article
    | Open Access

    Designing highly efficient chromophores comprising earth-abundant elements is essential for both light harvesting and electron transfer reactions. Here, authors prepare a copper purpurin complex that shows enhanced photocatalytic activity for CO2 reduction to CO with a high selectivity.

    • Huiqing Yuan
    • , Banggui Cheng
    •  & Zhiji Han
  • Article
    | Open Access

    Sunlight can change the composition of atmospheric aerosol particles, but the mechanisms through which this happens are not well known. Here, the authors show that fast radical reaction and slow diffusion near viscous organic particle surfaces can cause oxygen depletion, radical trapping and humidity dependent oxidation.

    • Peter A. Alpert
    • , Jing Dou
    •  & Markus Ammann
  • Article
    | Open Access

    Understanding the mechanism of non-radiative losses in organic photovoltaics is crucial to improve the performance further. Here, the authors use combined device and spectroscopic data to reveal universal model to maximise exciton splitting and charge separation by adjusting the energy of charge transfer state.

    • Nicola Gasparini
    • , Franco V. A. Camargo
    •  & Christoph J. Brabec
  • Article
    | Open Access

    Predicting the conversion and selectivity of a photochemical reactions is challenging. Here, the authors introduce a framework for the quantitative prediction of the time-dependent progress of a photoligation reaction and predict LED-light induced conversion through a wavelength-resolved numerical simulation.

    • Jan P. Menzel
    • , Benjamin B. Noble
    •  & Christopher Barner-Kowollik
  • Article
    | Open Access

    Vibronic coupling is a key feature of molecular electronic transitions, but its visualization in real space is an experimental challenge. Here the authors, using scanning tunneling microscopy induced luminescence, resolve the effect of vibronic coupling with different modes on the electron distributions in real space in a single pentacene molecule.

    • Fan-Fang Kong
    • , Xiao-Jun Tian
    •  & J. G. Hou
  • Article
    | Open Access

    Activation of narrow-bandgap photocatalysts holds key to applicable solar-to-hydrogen energy conversion. Here, the authors demonstrate effective sequential cocatalyst decoration for such narrow-bandgap photocatalysts to realise highly-efficient hydrogen evolution and Z-scheme water splitting.

    • Zheng Wang
    • , Ying Luo
    •  & Kazunari Domen
  • Article
    | Open Access

    Synthesis of peptides and proteins containing multiple disulfide bonds is challenging, limiting the elucidation of their biological functions. Here, the authors report a general synthetic strategy for fast formation of two and three disulfide bonds in peptides and proteins, and apply it to prepare several therapeutically important peptides.

    • Shay Laps
    • , Fatima Atamleh
    •  & Ashraf Brik
  • Article
    | Open Access

    Photodynamic inactivation is a common antibacterial method but often fails in extremely acidic environments (pH< 4). Here, the authors demonstrate halogenation of fluorescein for the development of a photodynamic agent which works in extremely acidic environments and demonstrate sterilisation applications in fruit juice and in vivo.

    • Ying Wang
    • , Jiazhuo Li
    •  & Peng Wu
  • Article
    | Open Access

    Photomediated-reversible-deactivation radical polymerisation has a limited scope of available photocatalysts due to multiple stringent requirements of properties. Here the authors show, an oxygen-mediated reductive quenching pathway for photoinduced electron transfer reversible addition-fragmentation chain transfer polymerisation.

    • Chenyu Wu
    • , Kenward Jung
    •  & Cyrille Boyer
  • Article
    | Open Access

    Organocatalytic atom transfer radical polymerization (O-ATRP) is attractive due to its metal-free nature but catalysts are rarely applied at a low loading. Here the authors introduce a catalyst design logic based on heteroatom-doping of polycyclic arenes, which led to the discovery of oxygen-doped anthanthrene as an organic photoredox catalysts for O-ATRP.

    • Qiang Ma
    • , Jinshuai Song
    •  & Saihu Liao
  • Article
    | Open Access

    The use of short wavelength light in photolysis applications in chemistry and biology is limited by photolytic reaction yields, photodamage and photobleaching. Here, the authors report a general long wavelength single photon driven photolysis method using a triplet-triplet annihilation process.

    • Ling Huang
    • , Le Zeng
    •  & Gang Han
  • Article
    | Open Access

    Achieving efficient photoelectrochemical cells requires insights into the ion kinetics at the surface of photoelectrode. Here, the authors show a new platform for investigating strong coupling between hydroxide ions and surface charge carriers by using monolayer InSe as the anode with high photocurrent density.

    • Haihong Zheng
    • , Yizhen Lu
    •  & Yang Cao
  • Article
    | Open Access

    Translating discovery scale vial-based batch reactions to continuous flow scale-up conditions is limited by significant time and resource constraints. Here, the authors report a photochemical droplet microfluidic platform, which enables high throughput reaction discovery in flow to generate pharmaceutically relevant compound libraries.

    • Alexandra C. Sun
    • , Daniel J. Steyer
    •  & Corey R. J. Stephenson
  • Article
    | Open Access

    Developing a new π-skeletal aromatic fused-ring for tuning material properties in organic electronics is still a challenge due to limited chemical approach. Here, the authors enrich the chemistry by synthesizing SiO-bridged ladder-type π-skeletons with enhanced planarity and deeper energy levels than CO-bridged counterpart.

    • Ying Qin
    • , Hui Chen
    •  & Dongbing Zhao
  • Article
    | Open Access

    Chiral functional materials with circularly polarized luminescence can be used in various applications but rarely reported. Here the authors show, a complex system, which show intense circularly polarized ultraviolet luminescence with large glum value, enabling a chiral UV light triggered enantioselective polymerization.

    • Dongxue Han
    • , Xuefeng Yang
    •  & Pengfei Duan
  • Article
    | Open Access

    Designing efficient organic solar cells is limited by the energy required to overcome the mutual Coulomb attraction between electron and hole. Here, the authors reveal long-lived and disorder-free charge-transfer states enable efficient endothermic charge separation in non-fullerene systems with marginal energy offset.

    • Ture F. Hinrichsen
    • , Christopher C. S. Chan
    •  & Philip C. Y. Chow
  • Article
    | Open Access

    Efficient photocatalytic hydrogen generation relies on highly choreographed delivery of protons and electrons to the reaction site such that they arrive just in time. Here, authors show that proton transport can be controlled by light with the photobase effect to increase H2 generation rate.

    • Jiawen Fang
    • , Tushar Debnath
    •  & Jacek K. Stolarczyk
  • Perspective
    | Open Access

    Photon-induced charge separation phenomena are at the heart of light-harvesting applications but challenging to be described by quantum mechanical models. Here the authors illustrate the potential of machine-learning approaches towards understanding the fundamental processes governing electronic excitations.

    • Florian Häse
    • , Loïc M. Roch
    •  & Alán Aspuru-Guzik
  • Article
    | Open Access

    Revealing the spatial distribution of hot carriers in real space is crucial to their efficient utilization. Here, the authors show that in-situ electrochemical tip-enhanced Raman spectroscopy is able to resolve the spatial distribution of reactive hot carriers with a nanometer spatial resolution.

    • Sheng-Chao Huang
    • , Xiang Wang
    •  & Bin Ren
  • Article
    | Open Access

    Understanding and predicting the kinetics of reverse intersystem crossing (RISC) facilitates the design of materials. Here, the authors demonstrate a theoretical expression that reproduces experimental RISC rate constants ranging over five orders of magnitude in selected molecules.

    • Naoya Aizawa
    • , Yu Harabuchi
    •  & Yong-Jin Pu