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Rational design of efficient pH-universal hydrogen evolution reaction (HER) catalysts to enable large-scale hydrogen production via electrochemical water splitting is of great significance, yet a challenging task. Herein, Ru atoms in the Ru2P structure were replaced with M=Co, Ni, or Mo to produce M2-xRuxP nanocrystals. The metals show strong site preference, with Co and Ni occupying the tetrahedral sites and Ru the square pyramidal sites of the CoRuP and NiRuP Ru2P-type structures. The presence of Co or Ni in the tetrahedral sites leads to charge redistribution for Ru and, according to density functional theory (DFT) calculations, to a significant increase in the Ru d-band centers. As a result, the intrinsic activity of CoRuP and 1 NiRuP increases considerably compared to Ru2P in both acidic and alkaline media. The effect is not observed for MoRuP, in which Mo prefers to occupy the pyramidal sites. In particular, CoRuP shows state-of-the-art activity, outperforming Ru2P with Pt-like activity in 0.5 M H2SO4 (η10=12.3 mV; η100=52 mV; turnover frequency (TOF)=4.7 s-1). It remains extraordinarily active in alkaline conditions (η10=12.9 mV; η100=43.5 mV) with a TOF of 4.5 s-1, which is 4x higher than that of Ru2P and 10x that of Pt/C. Further increase of the Co content does not lead to drastic loss of activity, especially in alkaline medium, where for example the TOF of Co1.9Ru0.1P remains comparable to that of Ru2P and higher than Pt/C, highlighting the viability of the adopted approach to prepare cost efficient catalysts.

One of the most promising routes for the future fabrication of solution-processable high-performance solar cells is to employ metal halide perovskites as photoactive material combined with organic semiconductors as charge extraction layers. An essential requirement to obtain high device performance is a proper energy level alignment across the device interfaces. Here, we investigate the interface between a triple cation perovskite and a prototypical electron acceptor molecule. Photoemission spectroscopy reveals a ground state charge transfer induced band bending on either side of the junction, which significantly alters the charge extraction barriers as compared to assumed vacuum level alignment and flat-band conditions. In addition, we demonstrate that upon white light illumination, the energy levels of the organic layer exhibit rigid shifts by up to 0.26 eV with respect to those of the perovskite, revealing a non-constant energy offset between the frontier energy levels of the two materials. Such level shifts of the organic transport layer are fully reversible upon switching on/off the light, indicating an electrostatic origin of this phenomenon caused by unbalanced distribution of photogenerated charge carriers. We therefore stress the importance of determining the energy level alignment at perovskite-based interfaces not only in the electronic ground state (dark) but also under device operating conditions (operando) to enable for a reliable correlation with the device performance.

Molecular doping is a key process to increase the density of charge carriers in organic semiconductors. Doping induced charges in polymer semiconductors result in the formation of polarons and or bipolarons due to the strong electron vibron coupling in conjugated organic materials. Identifying the nature of charge carriers in doped polymers is essential to optimize the doping process for applications. In this work, we use Raman spectroscopy to investigate the formation of charge carriers in molecularly doped poly 3 hexylthiophene 2,5 diyl P3HT for increasing dopant concentration, with the organic salt dimesityl borinium tetrakis penta fluorophenyl borate Mes2B [B C6F5 4] amp; 8722; and the Lewis acid tris pentafluorophenyl borane [B C6F5 3]. While the Raman signatures of neutral P3HT and singly charged P3HT segments polarons are known, the Raman spectra of doubly charged P3HT segments bipolarons are not yet sufficiently understood. Combining Raman spectroscopy measurements on doped P3HT thin films with first principles calculations on oligomer models, we explain the evolution of the Raman spectra from neutral P3HT to increasingly doped P3HT featuring polarons and eventually bipolarons at high doping levels. We identify and explain the origin of the spectral features related to bipolarons by tracing the Raman signature of the symmetric collective vibrations along the polymer backbone, which compared to neutral P3HT redshifts for polarons and blueshifts for bipolarons. This is explained by a planarization of the singly charged P3HT segments with polarons and rather high order in thin films, while the doubly charged segments with bipolarons are located in comparably disordered regions of the P3HT film due to the high dopant concentration. Furthermore, we identify additional Raman peaks associated with vibrations in the quinoid doubly charged segments of the polymer. Our results offer the opportunity for readily identifying the nature of charge carriers in molecularly doped P3HT while taking advantage of the simplicity, versatility, and non destructive nature of Raman spectroscopy

We have witnessed tremendous progress of metal halide perovskite (MHP)-based optoelectronic devices, especially in the field of photovoltaics. Despite intensive research in the past few years, questions still remain regarding their fundamental optoelectronic properties, among which the electronic properties exhibit an interplay of numerous phenomena that deserve serious scrutiny. In this Focus article, we aim to provide a contemporary understanding of the unique electronic properties that has been resolved by the community. First introducing some of the basic concepts established in semiconductor physics, the intrinsic and extrinsic electronic properties of the MHPs are disentangled and explained. With this, the complex interplay of interface-, dopant-, and surface state-induced electronic states in determining the electrostatic landscape in the material can be comprehended, and the energy level alignment in device architectures more reliably assessed.

A systematic spectroelectrochemical approach is presented to precisely determine frontier orbital energies of PM6:Y6 blends in device-relevant films and results are discussed regarding their impact on solar cell performance.

We introduce for the first time a core shell structure composed of nanostructured self standing titania nanotubes TNT, light absorber filled with Au nanowire AuNW array electrons collector applied to the photoelectrocatalytic water splitting. Its activity is four times higher than that of reference TNT Ti obtained with the same anodizing conditions. The composite photoanode brings a distinct photocurrent generation 8 mA cm amp; 8722;2 at 1.65 V vs. RHE , and a high incident photon to current efficiency of 35 obtained under UV light illumination. Moreover, the full system concept of selected constitutional materials, based on Au noble metal and the very stable semiconductor TiO2, ensures a stable performance over a long time range with no photocurrent loss during 100 on off cycles of light illumination, after 12 h constant illumination and after one month storage in air. We provide experimental evidence by photoelectron spectroscopy measurements, confirming that the electronic structure of TNT AuNW is rectifying for electrons and ohmic for holes, while the electrochemical characterization confirms that the specific architecture of the photoanode supports electron separation due to the presence of a Schottky type contact and fast electron transport through the Au nanowires. Although the composite material shows an unchanged electrochemical band gap, typical for plain TiO2, we find this material to be an innovative platform for efficient photoelectrochemical water splitting under UV light illumination, with significant potential for further modifications, for example extension into the visible light regime

With power conversion efficiencies of perovskite-on-silicon and all-perovskite tandem solar cells increasing at rapid pace, wide bandgap (> 1.7 eV) metal-halide perovskites (MHPs) are becoming a major focus of academic and industrial photovoltaic research. Compared to their lower bandgap (< 1.6 eV) counterparts, these types of perovskites suffer from higher levels of non-radiative losses in both the bulk material and in device configurations, constraining their efficiencies far below their thermodynamic potential. In this work, we investigate the energy losses in methylammonium (MA) free high-Br-content widegap perovskites by using a combination of THz spectroscopy, steady-state and time-resolved photoluminescence, coupled with drift-diffusion simulations. The investigation of this system allows us to study charge-carrier recombination in these materials and devices in the absence of halide segregation due to the photostabilty of formamidinium-cesium based lead halide perovskites. We find that these perovskites are characterised by large non-radiative recombination losses in the bulk material and that the interfaces with transport layers in solar cell devices strongly limit their open-circuit voltage. In particular, we discover that the interface with the hole transport layer performs particularly poorly, in contrast to 1.6 eV bandgap MHPs which are generally limited by the interface with the electron-transport layer. To overcome these losses, we incorporate and investigate the recombination mechanisms present with perovskites treated with the ionic additive 1-butyl-1-methylpipiderinium tetrafluoroborate. We find that this additive not only improves the radiative efficiency of the bulk perovskite, but also reduces the non-radiative recombination at both the hole and electron transport layer interfaces of full photovoltaic devices. In addition to unravelling the beneficial effect of this specific treatment, we further optimise our solar cells by introducing an additional LiF interface treatment at the electron transport layer interface. Together these treatments enable MA-free 1.79 eV bandgap perovskite solar cells with open-circuit voltages of 1.22 V and power conversion efficiencies approaching 17 %, which is among the highest reported for this material system.

In the last decade, perovskite semiconductors have triggered a revolution in solar cell research. However, critical issues remain concerning the stability of metal-halide perovskites, which need to be overcome to enable a large scale commercialisation of perovskite photovoltaics (PV). While the rather poor environmental stability of these perovskites is usually attributed to their ionic nature rendering them sensitive to moisture and oxygen, the actual contribution of mobile ions to the total degradation loss under different environmental conditions is poorly understood. In this work, we reveal that the initial degradation of perovskite semiconductors is largely the result of mobile ion-induced internal field screening - a phenomenon that has not been previously discussed in relation to the degradation of perovskite solar cells. The increased field screening leads to a decrease in the steady-state power conversion efficiency mainly due to a large reduction in current density, while the efficiency at high scan speeds (>1000 V/s) where the ions are immobilized is much less affected. We also show that interfacial recombination does not increase upon ageing, yet the open-circuit voltage (VOC) decreases as the result of an increase in the mobile ion density upon ageing. Furthermore, similar ionic losses appear under different external stressors, in particular when there are free charges present in the absorber layer. This work reveals a key degradation mechanism, providing new insights into initial device degradation before chemical or extrinsic mechanical device degradation effects manifest, and it highlights the critical role mobile ions play therein.

Atomic‐level manipulation of catalysts is important for both fundamental studies and practical applications. Here, the central metal atom in an atomically precise Ag25 nanocluster (NC) is replaced with a single Pd, Pt, and Au atom, respectively, and employed as a model system to study the structure–property–activity relationship at the atomic level. While the geometric structures are well‐preserved after doping, the electronic structures of Ag25 NCs are significantly altered. The combination of Ag25 and TiO2 enhances the charge separation at the interface, exhibiting a 10 times higher hydrogen production rate in photocatalytic hydrogen evolution reaction compared to bare TiO2. Further results show that heteroatoms doping has a negative impact on performance, particularly in the cases of Pd and Au doping. Ultraviolet photoelectron spectroscopy measurements and density functional theory calculations suggest that the lower activities are due to an energy mismatch between the levels of doped NCs and TiO2. These findings not only reveal the impact of heteroatoms doping on the electronic properties and photocatalytic activities of NCs, but can also guide the design of heterometallic NCs for photocatalytic applications., Heteroatoms doping alters the electronic structures of Ag25 nanoclusters (NCs), while keeping the geometric structures unchanged. In this way, the geometrical effects and the electronic effects are clearly distinguished. The photocatalytic activities of as‐prepared NCs deposited onto TiO2 are investigated. The performances follow the order of Ag25 ≥ PtAg24 > PdAg24 ≥ AuAg24. image © 2023 WILEY‐VCH GmbH

Aqueous processing of Ni rich layered oxide cathode materials is a promising approach to simultaneously decrease electrode manufacturing costs, while bringing environmental benefits by substituting the state of the art often toxic and costly organic processing solvents. However, an aqueous environment remains challenging due to the high reactivity of Ni rich layered oxides towards moisture, leading to lithium leaching and Al current collector corrosion because of the resulting high pH value of the aqueous electrode paste. Herein, a facile method was developed to enable aqueous processing of LiNi0.8Co0.1Mn0.1O2 NCM811 by the addition of lithium sulfate Li2SO4 during electrode paste dispersion. The aqueously processed electrodes retained 80 amp; 8201; of their initial capacity after 400 cycles in NCM811 graphite full cells, while electrodes processed without the addition of Li2SO4 reached 80 amp; 8201; of their capacity after only 200 cycles. Furthermore, with regard to electrochemical performance, aqueously processed electrodes using carbon coated Al current collector outperformed reference electrodes based on state of the art production processes involving N methyl 2 pyrrolidone as processing solvent and fluorinated binders. The positive impact on cycle life by the addition of Li2SO4 stemmed from a formed sulfate coating as well as different surface species, protecting the NCM811 surface against degradation. Results reported herein open a new avenue for the processing of Ni rich NCM electrodes using more sustainable aqueous routes

Structural and electrical properties of undoped and doped amp; 945; amp; 8722;Ga2O3 thin films grown by pulsed laser deposition on m plane sapphire in a two step process are presented. A buffer layer of undoped amp; 945; amp; 8722;Ga2O3 is introduced below the electrically active thin film to improve the crystal quality and enable the stabilization of the amp; 945; phase at lower substrate temperatures for sufficient dopant incorporation. Donor doping of the active layers with tin, germanium and silicon, respectively, is realized below a critical substrate temperature of 600 C. Depth resolved X ray photoelectron spectroscopy measurements on tin doped samples reveal a lower amount of tin in the bulk thin film compared to the surface as well as a lower tin incorporation for higher substrate temperatures, indicating desorption or float up processes that determine the incorporation of the dopants. Electron mobilities as high as 17 amp; 8202;cm2V amp; 8722;1s amp; 8722;1 at 1.4 1019 amp; 8202;cm amp; 8722;3 and 37 amp; 8202;cm2V amp; 8722;1s amp; 8722;1 at 3.7 1018 amp; 8202;cm amp; 8722;3 are achieved for tin and germanium doped amp; 945; amp; 8722;Ga2O3 thin films, respectively. Further, a narrow window of suitable annealing temperature from 680 K to 700 K for obtaining ohmic Ti Al Au layer stacks was identified. For higher annealing temperatures a deterioration of the electrical properties of the thin films was observed suggesting the need for developing low temperature contacting procedures for amp; 945; amp; 8722;Ga2O3 based devices

Summary Van der Waals organic/inorganic heterostructures in the two-dimensional (2D) limit with extensive structural tunability will advance the development of artificial solids with tailored functionalities. Recent breakthroughs in several types of 2D organic materials, including molecular monolayer films, 2D polymers, covalent-organic frameworks, and metal oxide frameworks, have greatly enriched the design possibilities of heterostructures with inorganic 2D materials. This review provides a timely summary of the latest advances in synthesis approaches toward advanced organic/inorganic heterostructures, answers the fundamental questions regarding the interfacial interactions in the 2D limit, and further highlights the uses of such organic/inorganic heterostructures in advanced transistors, optoelectronics, neuromorphic, and other multifunctional devices with unique capabilities.

In this study, the kinetics of the adsorption of 2,3,5,6 tetrafluoro 7,7,8,8 tetracyanoquinodimethane F4TCNQ on the surface of Ag nanoparticles Ag NPs in chloroform has been intensively investigated, as molecular doping is known to play a crucial role in organic electronic devices. Based on the results obtained from UV visible vis near infrared NIR absorption spectroscopy, cryogenic transmission electron microscopy, scanning nanobeam electron diffraction, and electron energy loss spectroscopy, a two step interaction kinetics has been proposed for the Ag NPs and F4TCNQ molecules, which includes the first step of electron transfer from Ag NPs to F4TCNQ indicated by the ionization of F4TCNQ and the second step of the formation of a Ag F4TCNQ complex. The whole process has been followed via UV vis NIR absorption spectroscopy, which reveals distinct kinetics at two stages the instantaneous ionization and the long term complex formation. The kinetics and the influence of the molar ratio of Ag NPs F4TCNQ molecules on the interaction between Ag NPs and F4TCNQ molecules in an organic solution are reported herein for the first time. Furthermore, the control experiment with silica coated Ag NPs manifests that the charge transfer at the surface between Ag NPs and F4TCNQ molecules is prohibited by a silica layer of 18 nm

Abstract Pseudomorphic and relaxed $$\alpha$$ α -(Al$$_x$$ x Ga$$_{1-x}$$ 1 - x )$$_2$$ 2 O$$_3$$ 3 thin films are grown by combinatorial pulsed laser deposition in the entire composition range on prismatic a- and m-plane $$\alpha$$ α -Al$$_2$$ 2 O$$_3$$ 3 substrates. Pseudomorphic growth on m-plane sapphire has been achieved for $$x \ge 0.45$$ x ≥ 0.45 . A distinct difference between the a- and m-epitaxial plane is observed in reciprocal space map measurements being in agreement with continuum elasticity theory for rhombohedral heterostructures. While pseudomorphic layers on m-plane sapphire show a pronounced shear strain $$e'_5$$ e 5 ′ along the c-axis direction, relaxed layers exhibit a global lattice tilt in the same direction. Both effects are not present on the a-epitaxial plane. Out-of-plane lattice constants as well as $$e'_5$$ e 5 ′ are modeled as function of x employing elasticity theory, confirming theoretical values of the elastic stiffness tensor for $$\alpha$$ α -Ga$$_2$$ 2 O$$_3$$ 3 , especially the non-zero value of the $$C_{14}$$ C 14 component. Possible pyramidal slip systems for strain relaxation in c-axis direction are examined to explain and numerically model the difference in lattice tilt for the two substrate orientations. Graphic abstract

The double ionization of molecular dopants enables the doping efficiency free charges per dopant molecule to rise above 100 . However, the current models of doped organic semiconductors based on Fermi Dirac statistics fail to explain the double ionization of dopants and also the analogous situation of bipolaron formation on a host polymer. Here, we address this shortcoming by considering the renormalization of the state energies upon electron transfer between host and p dopant. We vary the model parameters amp; 9472;the reorganization energy and evolutions of ionization energies and electron affinities upon charging amp; 9472;and plot the fractions of doubly ionized, singly ionized, and neutral species. The model shows good agreement with experimental measurements of doubly ionized p dopants and bipolarons on a p doped polymer. With these insights, we suggest that the state energy renormalization upon charging is the key parameter to be minimized for double ionization of dopants or maximized to avoid formation of bipolarons on the host

Blending organic molecules to tune their energy levels is currently being investigated as an approach to engineer the bulk and interfacial optoelectronic properties of organic semiconductors. It has been proven that the ionization energy and electron affinity can be equally shifted in the same direction by electrostatic effects controlled by blending similar halogenated derivatives with different energetics. Here we show that the energy gap of organic semiconductors can also be tuned by blending. We use oligothiophenes with different numbers of thiophene rings as an example and investigate their structure and electronic properties. Photoelectron spectroscopy and inverse photoelectron spectroscopy show tunability of the single-particle gap, with the optical gaps showing similar, but smaller, effects. Theoretical analysis shows that this tuning is mainly caused by a change in the dielectric constant with blend ratio. Further studies will explore the practical impact of this energy-level engineering strategy for optoelectronic devices.

Direct detection of intrinsic defects in halide perovskites HaPs by standard methods utilizing optical excitation is quite challenging, due to the low density of defects in most samples of this family of materials lt; 10 15 cm 3 in polycrystalline thin films and lt; 10 11 cm 3 in single crystals, except melt grown ones . While several electrical methods can detect defect densities lt;10 15 cm 3, such as deep level transient spectroscopy DLTS or thermally stimulated current TSC , they require preparation of ohmic and or rectifying electrical contacts to the sample, which not only poses a challenge by itself in the case of HaPs but also may create defects at the contact HaP interface and introduce extrinsic defects into the HaP. Here, we show that low energy photoelectron spectroscopy measurements can be used to obtain directly the energy position of gap states in Br based wide bandgap E g gt; 2 eV HaPs. By measuring HaP layers on both hole and electron contact layers, as well as single crystals without contacts, we conclude that the observed deep defects are intrinsic to the Br based HaP, and we propose a passivation route via the incorporation of a 2D forming ligand into the precursor solution

We introduce for the first time a core-shell structure composed of nanostructured self-standing titania nanotubes (TNT, light absorber) filled with Au nanowire (AuNW) array (electrons collector) applied to the photoelectrocatalytic water splitting. Its activity is four times higher than that of reference TNT-Ti obtained with the same anodizing conditions. The composite photoanode brings a distinct photocurrent generation (8 mA cm

The ability to insolubilize doped semiconducting polymer layers can help enable the fabrication of efficient multilayer solution-processed electronic and optoelectronic devices. Here, we present a promising approach to simultaneously n-dope and largely insolubilize conjugated polymer films using tetrakis[{4-(1,3-dimethyl-2,3-dihydro-1

A thermal atomic layer deposition (ALD) process to fabricate MoS2 thin films is successfully demonstrated by using cycloheptatriene molybdenum tricarbonyl (C7H8Mo(CO)3) and H2S as precursors at an ALD temperature below 300 °C. The process is systematically investigated, showing a typical self‐limiting characteristic within an ALD temperature window of 225–285 °C and a high growth‐per‐cycle of 0.11 nm. The as‐deposited films are amorphous while they can be crystallized in situ by sulfurization with H2S at a low temperature of 300 °C. A prototypical application of the developed ALD process is demonstrated by constructing a MoS2/TiO2 heterostructure through depositing MoS2 onto anodized TiO2 nanotubes for photoelectrochemical water splitting. The MoS2/TiO2 heterostructures exhibit approximately three times superior photoelectrochemical performance than the pristine TiO2 nanotubes. This is attributed to an enhanced visible light‐harvesting ability of MoS2 and an improved separation of the photo‐generated charge carriers at the heterostructure interface, which is affirmed by a staggering gap (type II) between MoS2 and TiO2 as probed by ultraviolet photoelectron spectroscopy. Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659 Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659

A poly(methacrylate) with benzocyclobutene side chains, CL, has been synthesized by radical polymerization for use as a crosslinking additive for a previously reported benzocyclobutene-functionalized fullerene, PCBCB, which can be thermally insolubilized following solution processing. Films of PCBCB incorporating CL and n-doped with (IrCp*Cp)2 exhibit in-plane electrical conductivities around ten times higher than those of n-doped films without CL, while the use of CL also reduces leaching of dopant ions from the film upon washing. The performance and stability of perovskite solar cells using insolubilized PCBCB:CL, insolubilized PCBCB, or PCBM as top electron-extraction layers are compared; cells with undoped PCBCB:CL extraction layers exhibit higher average and maximum power conversion efficiencies (16 and 18.5%, respectively) than their PCBM and PCBCB counterparts. Devices with undoped PCBCB:CL extraction layers also showed excellent thermal stability, retaining 92% of their stabilized power output after aging for 3000 h at 85 °C in the dark in a nitrogen atmosphere.

Graphdiyne polymers have interesting electronic properties due to their π-conjugated structure and modular composition. Most of the known synthetic pathways for graphdiyne polymers yield amorphous solids because the irreversible formation of carbon–carbon bonds proceeds under kinetic control and because of defects introduced by the inherent chemical lability of terminal alkyne bonds in the monomers. Here, we present a one-pot surface-assisted deprotection/polymerisation protocol for the synthesis of crystalline graphdiynes over a copper surface starting with stable trimethylsilylated alkyne monomers. In comparison to conventional polymerisation protocols, our method yields large-area crystalline thin graphdiyne films and, at the same time, minimises detrimental effects on the monomers like oxidation or cyclotrimerisation side reactions typically associated with terminal alkynes. A detailed study of the reaction mechanism reveals that the deprotection and polymerisation of the monomer is promoted by Cu(ii) oxide/hydroxide species on the as-received copper surface. These findings pave the way for the scalable synthesis of crystalline graphdiyne-based materials as cohesive thin films., We present a one-pot deprotection/polymerisation protocol for the synthesis of crystalline graphdiynes on top of a copper surface starting with stable trimethylsilylated alkyne monomers.

Tailor-made electrode work functions are indispensable to control energy-level offsets at the interfaces of (opto-)electronic devices. We show by means of photoelectron spectroscopy that several na...

Perovskites offer exciting opportunities to realize efficient multijunction photovoltaic devices. This requires high-VOC and often Br-rich perovskites, which currently suffer from halide segregatio...

The mechanism and the nature of the species formed by molecular doping of the model polymer poly(3-hexylthiophene) (P3HT) in its regioregular (rre-) and regiorandom (rra-) forms in solution are investigated for three different dopants: the prototypical π-electron acceptor 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ), the strong Lewis acid tris(pentafluorophenyl)borane (BCF), and the strongly oxidizing complex molybdenum tris[1-(methoxycarbonyl)-2-(trifluoromethyl)ethane-1,2-dithiolene] (Mo(tfd-CO2Me)3). In a combined optical and electron paramagnetic resonance study, we show that the doping of rreP3HT in solution occurs by integer charge transfer, resulting in formation of P3HT radical cations (polarons) for all of the dopants considered here. Remarkably, despite the different chemical nature of the dopants and dopant–polymer interaction, the formed polarons exhibit essentially identical optical absorption spectra. The situation is very different for the doping of rraP3HT, where we observe formation of a charge-transfer complex with F4TCNQ and of a “localized” P3HT polaron on nonaggregated chains upon doping with BCF, while there is no indication of dopant-induced species in the case of Mo(tfd-CO2Me)3. We estimate the ionization efficiency of the respective dopants for the two polymers in solution and report the molar extinction coefficient spectra of the three different species. Finally, we observe increased spin delocalization in regioregular compared to regiorandom P3HT by electron nuclear double resonance, suggesting that the ability of the charge to delocalize on aggregates of planarized polymer backbones plays a significant role in determining the doping mechanism.

Coordination polymers (CPs) and metal-organic frameworks (MOFs) have emerged as versatile precursors for transition-metal phosphides catalysts. However, the controlled synthesis of CPs-derived bime...

The electrical and optoelectronic properties of organic semiconductor thin films can be tailored by mixing two molecular materials, e.g., by co-deposition. Possible resulting morphologies include p...

The deposition of an atomically precise nanocluster, for example, Ag44(SR)30, onto a large‐band‐gap semiconductor such as TiO2 allows a clear interface to be obtained to study charge transfer at the interface. Changing the light source from visible light to simulated sunlight led to a three orders of magnitude enhancement in the photocatalytic H2 generation, with the H2 production rate reaching 7.4 mmol h−1 gcatalyst −1. This is five times higher than that of TiO2 modified with Ag nanoparticles and even comparable to that of TiO2 modified with Pt nanoparticles under similar conditions. Energy band alignment and transient absorption spectroscopy reveal that the role of the metal clusters is different from that of both organometallic complexes and plasmonic nanoparticles: A type II heterojunction charge‐transfer route is achieved under UV/Vis irradiation, with the cluster serving as a small‐band‐gap semiconductor. This results in the clusters acting as co‐catalysts rather than merely photosensitizers., Multitasking: Metal nanoclusters are not merely photosensitizers, they can also act as co‐catalysts under appropriate conditions. Deposition of the atomically precise nanocluster Ag44(thiolate)30 onto a large‐band‐gap semiconductor such as TiO2 led to a type II heterojunction charge‐transfer route being achieved on irradiation with UV/Vis light, with the cluster serving as a small‐band‐gap semiconductor, rather than merely a photosensitizer.