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CsPbBr3 perovskite exhibits potential application in photocatalytic CO2 reduction into valuable chemical fuels; however, enhancing carrier separation capability of the CsPbBr3 and fully understanding the CO2 reduction reaction process are still imperative. Herein, a new series of xSnS2/CsPbBr3 nanocrystals (NCs)‐y heterostructures are developed, which exhibit better catalytic activity in comparison with pure CsPbBr3 NCs. Interface and surface carrier dynamic investigation reveals that this heterojunction structure can effectively improve carrier separation efficiency. Based on the interfacial electric field direction of CsPbBr3 to SnS2, it is suggested that SnS2/CsPbBr3 NC heterostructure satisfies Z‐scheme transfer dynamics. Meanwhile, by the aid of in situ surface photovoltage, it is experimentally confirmed there is dynamic carrier interaction between CO2 molecules and the SnS2/CsPbBr3 NCs photocatalyst under irradiation, and a photocatalytic CO2 reduction mechanism is thus proposed. This work expands the awareness of the interaction between CO2 and the photocatalyst, which can be strongly influenced by carrier separation efficiency at the photocatalyst heterojunction. [ABSTRACT FROM AUTHOR]

Abstract: Although NiCoP has attracted much attention in the field of electrocatalysis, the study of its photocatalytic activity and mechanism have been somewhat limited. NiCoP/g‐C3N4, synthesized by simple one‐pot method, is a highly efficient photocatalyst for hydrogen production from water. NiCoP/g‐C3N4 exhibits a hydrogen evolution rate of 1643 μmol h−1 g−1, which is 21 times higher than that of bare g‐C3N4. The excellent performance is due to a combination of improved separation efficiency and effective charge transfer efficiency. The photogenerated charge behavior is characterized by the surface photovoltage (SPV), transient photovoltage (TPV), and photoluminescence spectroscopy. The photogenerated charge transport is investigated by electrochemical impedance spectroscopy and polarization curve. Moreover, the effective charge transfer efficiency was measured according to the mimetic apparent quantum yield. SPV and TPV measurements, whereby 10 vol % of a triethanolamine–water mixture was added into the testing system, were taken to simulate the real atmosphere for photocatalytic reaction, which can give rise to the photogenerated charge transfer process. A possible photocatalytic mechanism was also proposed. This study may provide an efficient theoretical basis to design transition metal phosphide cocatalyst‐modified photocatalysts. [ABSTRACT FROM AUTHOR]

With the purpose of high-efficiency separation of photo-generated charges and an improved photocatalytic performance, herein we report novel heterojunctions of p-type BiOBr and n-type ZnO constructed by loading amounts of BiOBr nanoflakes onto the surface of ZnO nanoflowers via a two-step hydrothermal/solvothermal method. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and UV-vis diffuse reflectance spectroscopy (UV-vis DRS) are employed to characterize the as-synthesized nanomaterials. The results indicate that p–n heterojunctions formed between BiOBr and ZnO. When evaluated as a photocatalyst for methyl orange (MO) decolorization, BiOBr–ZnO-40 shows excellent photocatalytic activity, superior to that of pristine BiOBr and ZnO. Notably, the photochemical process for the MO decolorization is elucidated by reactive species trapping and hydroxyl radical quantification experiments, suggesting that ṖOH and O2Ṗ− are the main oxygen active species for BiOBr–ZnO heterojunctions in the MO decolorization. Moreover, the separation and transfer process of photo-generated charges at the surface or interface of the BiOBr–ZnO composites is also investigated by means of surface photovoltage (SPV). On the basis of experimental and theoretical results, the enhanced photocatalytic activity mechanism for the BiOBr–ZnO heterojunctions is proposed. The effective separation and transfer of photo-generated charges are responsible for an improved photocatalytic performance due to the existence of the interfacial electric field located between BiOBr and ZnO. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) BiVO4/Bi2WO6 composite microspheres with enhanced visible-light (λ ＞ 420 nm) photodegradation activity of methylene blue (MB) were synthesized by a simple, one-pot, template-free solvothermal method. A mixture of ethylene glycol (EG) and H2O (volume ratio of EG-H2O was 1 : 1) was used as the solvent. To investigate the relationship between structure and photocatalytic performance, the as-synthesized samples were characterized by XRD, FESEM, HRTEM, UV-vis DRS, SPS and TPV. Structural characterizations indicated that the composite nanostructure mainly consisted of two single-crystal phases, which were BiVO4 and Bi2WO6. In addition, a possible growth mechanism of this microsphere composite and the separation process of photoinduced charge carriers in the heterojunction are discussed. [ABSTRACT FROM AUTHOR]

CuS/Zn0.8Cd0.2S composites have been successfully prepared by simple hydrothermal and cation exchange method. The Cu species loaded on Zn0.8Cd0.2S, together with the intimate contact formed between CuS and Zn0.8Cd0.2S, was clearly demonstrated with X-ray photoelectron spectroscopy and transmission electron microscopy. The optimized CuS/Zn0.8Cd0.2S photocatalyst has a high H2 evolution rate of 2792 μmol g−1 h−1 at CuS content of 3 wt% and the apparent quantum efficiency of 36.7% at 420 nm. The photophysical mechanism of the photocatalytic activity was investigated with the help of surface photovoltage spectroscopy (SPS) and transient photovoltage (TPV) techniques. The results revealed that photogenerated charge separation efficiency in Zn0.8Cd0.2S was enhanced and the photogenerated electrons were trapped by the loaded CuS, which benefits photo-reduction. Those were the reasons for significant enhancement in the photocatalytic H2 evolution from water splitting. [ABSTRACT FROM AUTHOR]

Abstract: An original photoelectric gas sensor, fabricated by Ru(dcbpy)2(NCS)2 (dcbpy=2,2′-bipyridyl-4,4′-dicarboxylate)(RuN3)-sensitized ZnO on a comb-like electrode by surface photocurrent technique with excitation of visible light (545nm), is presented for CO and O2 detection at room temperature. The surface photocurrent (I SPC) of a sample can be dramatically enhanced and diminished depending on the properties of the gases. As a reductive gas, CO can make I SPC increase and the sensor response is linear to the change in CO concentration with a detection limit of 0.62Torr. However, I SPC decreases upon O2 adsorption, since it can capture electrons from the surface. There is no linear dependency between I SPC and concentration of O2. In this article a microscopic mechanism of the photoelectric gas sensor has also been discussed in detail. This research should be valuable for the practical application of the ZnO gas sensor. [Copyright &y& Elsevier]

In this paper, ZnO nanoparticles were prepared by a sol–gel method and sensitized by azo pigment (4,4′-2-{N-[β-hydroxyl-γ-(ρ-nitroanilino)naphthyl]}azodiphenyl). Measurements of surface photocurrent by comb-like electrode and He–Ne laser and gas adsorption were performed on the ZnO/azo system. The process of photoinduced charge transport from excited dyes to nanocyrstalline ZnO was studied by surface photocurrent response (SPR). We have also discussed different effects of water and oxygen as gas adsorbates on SPR. Such a research should be valuable for the practical application of ZnO nanoparticles to semiconductor gas sensors. [Copyright &y& Elsevier]

In this study, surface photovoltages of titanyl phthalocyanine (TiOPc) and chloroaluminum phthalocyanine (AlClPc) were explored using surface photovoltage spectrum (SPS) technique and field-induced photovoltage spectrum (FISPS) technique. The experimental results show that in the region of 300–800 nm both the metallophthalocyanines give two surface photovoltage response bands corresponding to Soret-band (300–420 nm) and Q-band (500–800 nm), respectively, with Bethe splitting of Q-band. It was experimentally confirmed that the two bands of TiOPc and AlClPc result from electron transition of the same type, π–π* transition. From the results of FISPS it was inferred that TiOPc has p-type character and AlClPc has n-type character. It is coincided with the result of the optimal phase of SPV response. Also it was found that the generation efficiency of photocarriers for TiOPc was nearly not affected by the alternation of the sign of the external electrical field. It is different from AlClPc. Since the precursor of photogenerated free carrier for TiOPc is known to be of charge-transfer state, this observation should be an indication that the precursor for AlClPc has an other than the charge-transfer state. [Copyright &y& Elsevier]

By the aid of transient photovoltage, photo-generated carrier transfer mechanism of SnS 2 /g-C 3 N 4 composite has been suggested by interfacial electric field direction. Constructing heterojunction is an effective way to improve the photo-generated carrier separation efficiency and photocatalytic activity. Here, we construct SnS 2 /g-C 3 N 4 heterojunctions by in-situ growth of SnS 2 on the g-C 3 N 4. By adjusting annealing temperatures, the SnS 2 /g-C 3 N 4 -180 and SnS 2 /g-C 3 N 4 -120 samples could meet Z-scheme carrier transfer mechanism and conventional type-II charge transfer mechanism, respectively. By the aid of surface photovoltage spectra, the photo-generated carrier transfer direction and the driving force of the charge transfer are suggested. This difference in these two charge transfer mechanisms is supposed to be mainly related to the discrepancy in work functions of the SnS 2 treated at different temperatures. This work provides an effective method to understand the Z-scheme carrier transfer mechanism, which could help us to design Z-scheme photocatalysts for higher hydrogen evolution activity. [ABSTRACT FROM AUTHOR]

An effective scheme and technical means for understanding the mechanism of interfacial charge transfer. [Display omitted] • The Z-scheme Ti-ZFO/In 2 O 3 photoelectrode was successfully constructed. • Ti-ZFO/In 2 O 3 reaches 2.2 mA/cm2 at 1.23 V vs. RHE, which is 7 times that of pure Ti-ZFO. • The Z-scheme Ti-ZFO/In 2 O 3 could promote the separation and transfer of charges effectively. • This work provides an effective method and technical means to understanding the Z-scheme mechanism. Ti-ZnFe 2 O 4 photoanode has attracted extensive attention in photoelectrochemical (PEC) water oxidation due to its narrow band gap and good photostability. However, its low efficiency limits its development. Herein, we designed and constructed direct Z-scheme Ti-ZnFe 2 O 4 /In 2 O 3 (Ti-ZFO/In 2 O 3) photoanode. Under the interface electric field, photogenerated holes with stronger oxidation capacity on In 2 O 3 are retained to participate in the water oxidation reaction, and the photocurrent density of Ti-ZFO/In 2 O 3 is much higher than that of pure Ti-ZFO, reaching 2.2 mA/cm2 at 1.23 V vs. RHE. Kelvin Probe, steady-state photovoltage spectroscopy (SPV), transient photovoltage spectroscopy (TPV) and in-situ double beam strategy were used to demonstrate the Z-scheme charge transfer mechanism of Ti-ZFO/In 2 O 3 photoanode. Our work provides an effective scheme and technical means for further understanding the mechanism of interfacial charge transfer. [ABSTRACT FROM AUTHOR]

The slow kinetics of water oxidation has become a challenge for photoelectrochemical hydrogen production. Here, a novel organic-inorganic integrated photoanode system was constructed by using MIL-53(Fe) formed during the in-situ etching process as a cocatalyst to modify Ti–Fe 2 O 3. The photocurrent density of Ti–Fe 2 O 3 /MIL-53(Fe) reaches 2.5 mA/cm2, 10 times that of bare Ti–Fe 2 O 3 at 1.23 V vs. RHE, and the water oxidation photocurrent onset potential shifts 105 mV negatively. Ti–Fe 2 O 3 /MIL-53(Fe) reaches 52% at 390 nm for IPCE. The excellent photoelectrochemical performance is due to iron oxide clusters boost charge separation and transfer, in-situ etching exposes more reactive sites, and the tight connection reduces interfacial resistance, which greatly accelerates the surface kinetics of Ti–Fe 2 O 3. The in-depth understanding is provided for in-situ modification of photoanodes by metal organic frameworks in this work. The in-depth understanding is provided for in-situ modification of photoanodes by metal organic frameworks in this work. [Display omitted] • Ti–Fe 2 O 3 /MIL-53(Fe) photoelectrode was successfully constructed. • Ti–Fe 2 O 3 /MIL-53(Fe) reaches 2.5 mA/cm2 at 1.23 V vs. RHE, which is 10 times that of bare Ti–Fe 2 O 3. • MIL-53(Fe) greatly improves the water oxidation reaction kinetics of Ti–Fe 2 O 3. • This work provides a new insight into charge transfer in inorganic-organic hybrid systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel Z-scheme NH 2 -MIL-125(Ti)/Ti-Fe 2 O 3 photoanode is designed and constructed. • NH 2 -MIL-125(Ti)/Ti-Fe 2 O 3 shows excellent PEC performance and stability. • The Z-scheme pathway is identified by surface photovoltage, ESR and fs-TAS. • Efficient separation of interface and surface carriers is simultaneously realized. The construction of Z-scheme charge transfer pathways simulating natural photosynthesis is considered a promising method for improving reaction driving forces. Here, we modified the surface of titanium doped Fe 2 O 3 (Ti-Fe 2 O 3) nanorods with NH 2 -MIL-125(Ti) (Ti-MOFs) and a promising organic-inorganic hybrid Z-scheme NH 2 -MIL-125(Ti)/Ti-Fe 2 O 3 was successfully prepared. At 1.23 V vs. RHE, the photocurrent density of the composite photoanode reaches 2.67 mA/cm2, which is 5 times higher than that of Ti-Fe 2 O 3. The results of surface photovoltage, ESR and fs-TAS indicate that this improvement is mainly due to the effective Z-scheme charge transfer mechanism providing a strong driving force for charge separation and transport, greatly suppressing carrier recombination and allowing carriers with strong oxidation ability to participate in water oxidation. Meanwhile, NH 2 -MIL-125(Ti) can enhance light absorption and reduce the surface defect state of Ti-Fe 2 O 3. This study not only provides a feasible approach for the photoanode water splitting of traditional inorganic semiconductor/MOF based heterostructures, but also provides rich and effective means for revealing Z-scheme charge transfer mechanism in depth. [ABSTRACT FROM AUTHOR]

Cobalt-based metal-organic frameworks (Co-MOFs) are considered excellent cocatalysts for improving the photoelectrochemical performance of photoanodes. Considering the boundedness of monometallic MOFs, introducing a second metal is an efficient method to enhance the activity and stability of Co-MOFs. In this work, Cu doped Co-MOFs was successfully decorated on Ti–Fe 2 O 3 to prepare Ti–Fe 2 O 3 /CoCu-MOF. The photocurrent density of composite photoanode at 1.23 V vs. RHE reaches 2.06 mA/cm2, 5.5 times higher than that of Ti–Fe 2 O 3 , and the onset potential shifts 170 mV negatively. The results showed that CoCu-MOFs thin layer not only provided abundant active sites, but also effectively passivated the acceptor surface states of Ti–Fe 2 O 3 , thus inhibiting surface charge recombination. In addition, the introduction of Cu2+ can induce the generation of higher valence Co species, which significantly promotes the transfer of holes from Ti–Fe 2 O 3 to the electrolyte. Our work demonstrates a new and promising photoelectrochemical cocatalyst, and provides a convenient method for the construction of other bimetallic MOFs materials. This work has gained a deeper understanding of the impact of CoCu-MOFs on photoanode water oxidation, and provided new strategies for the application of other bimetallic MOFs in the field of energy conversion. [Display omitted] [ABSTRACT FROM AUTHOR]

In this respect, surface photovoltage spectrum (SPV) has been employed to analyze the carrier transfer mechanism of Ti/α-Fe 2 O 3 /g-C 3 N 4 composite photocatalyst system for the first time. That is, photo-generated carrier interfacial transfer direction is suggested to be the charge driving force between Ti/α-Fe 2 O 3 and g-C 3 N 4 , which could determine the Z -scheme carrier transfer mechanism of Ti/α-Fe 2 O 3 /g-C 3 N 4 photocatalysts. This work provides an effective method to understand the Z -scheme carrier transfer mechanism and could help us to design more effective Z -scheme photocatalysts systems. Unlabelled Image • A new method in understanding the Z -scheme carrier transfer mechanism. • Surface photovoltage spectrum is employed to analyze carrier transfer mechanism. • Ti/α-Fe 2 O 3 /g-C 3 N 4 Z-Scheme photocatalyst system is adopted. • Z-scheme transfer system is analyzed from driving force between the interface. [ABSTRACT FROM AUTHOR]

Inevitable drawbacks on α-Fe 2 O 3 photoanodes, such as poor conductivity, short hole diffusion length, high electron-hole recombination rate, limit their photoelectrochemical (PEC) performance for water oxidation. The construction of heterojunction is an effective approach to improve the PEC performance of photoanodes. Herein, we report the design of the WO 3 /Ti–Fe 2 O 3 heterojunction photoanodes, which are synthesized by two simple hydrothermal method. The optimized WO 3 /Ti–Fe 2 O 3 photoanode shows remarkably improved photocurrent of 2.15 mA/cm2 at 1.23 V versus reversible hydrogen electrode (RHE) without additional cocatalyst, which is higher than that of previous literatures. The improvement benefits from reduced charge transfer resistance in the bulk of Ti–Fe 2 O 3 photoanode and improved charge separation efficiency, which can been further confirmed by electrochemical impedance spectroscopy (EIS), the transient photovoltage (TPV) and the work function (WF) measurement. The present work also provide new opportunities in developing high performance photoanodes for PEC water splitting. WO 3 served as an electron transfer layer can reduce the resistance of interface charge transfer and improve the charge separation efficiency of Ti–Fe 2 O 3. However, charge separation efficiency is closely related to charge injection efficiency, therefore, more holes of Ti–Fe 2 O 3 will transfer to electrolyte to participate in the water oxidation. Image 1 • WO 3 served as an electron transfer layer can reduce the resistance of interface charge transfer. • The introduction of WO 3 can improve the charge separation efficiency of Ti–Fe 2 O 3. • The separation and transfer process of photogenerated charge carriers have been discussed. [ABSTRACT FROM AUTHOR]

Plasmon-enhanced bulk charge separation and migration at Au-CdS interfaces through CDs as the quicker transfer channel, and it is proved that the regulated charge movement pathway and migration dynamic could efficiently accelerate the photocatalytic hydrogen production rate via morphological and interfacial engineering. [Display omitted] • Core-double shelled Au@CDs@CdS NPs are fabricated for photocatalytic H 2 production. • Plasmon effect enhances interfacial charge separation within the bulk of CdS. • CDs act as faster charge migration channels between Au nucleus and CdS outer shell. • The investigations of charge transport dynamics are supported by SPV/TPV methods. The exploitation of morphological engineering strategies enables the design of semiconductor-based photocatalysts with a precision that significantly enhances their photocatalytic activity. In this study, a paradigm has been provided that embeds plasmonic nanostructures within the bulk of the semiconductor, which demonstrates an improvement in interfacial charge transfer and separation. It involves a distinct core-double shelled Au@carbon dots@CdS hybrid, exhibiting excellent photocatalytic H 2 generation under the visible light radiation. The interfacial engineering between the plasmonic nucleus and the semiconductor shell has been performed by the incorporation of carbon dots as faster charge channels. The effective driving force for plasmon-enhanced bulk charge separation of semiconductors and the unhindered interfacial charge transmission derived from carbon dots have been demonstrated by the use of steady state surface photovoltage (SPV) and transient state surface photovoltage (TPV) methods, as well as some intrinsic kinetics information of interfacial photoexcited charge carriers transfer processes. [ABSTRACT FROM AUTHOR]

CuInS 2 and CdS quantum dots (QDs) are sequentially assembled onto mesoporous TiO 2 film to prepare a CuInS 2 /CdS co-sensitized photoelectrode for QD-sensitized solar cell (QDSC) application. Our results show that the performance of a QDSC is strongly dependent on the order of CuInS 2 and CdS respected to the TiO 2 . When CuInS 2 is in between TiO 2 and CdS, the power conversion efficiency could reach 0.90%, while the efficiency decreased dramatically when the CuInS 2 QDs were on top of the layer (0.08%). Surface photovoltage (SPV) measurement revealed that the charge transfer from the cosensitizers toward the TiO 2 is much more efficient in the TiO 2 /CuInS 2 /CdS electrode rather than in the TiO 2 /CdS/CuInS 2 electrode. From the information on time-resolved photoluminescence (TRPL) technique, it was found that the average photoluminescence (PL) lifetime of TiO 2 /CuInS 2 /CdS electrode is shorter than that of the TiO 2 /CdS/CuInS 2 electrode, suggesting the higher carrier transfer rates between the heterointerfaces of CuInS 2 /CdS and TiO 2 /QDs. This study reported herein propose an innovative route to investigate the role of heterointerface in the carrier transfer mechanism and enable better design of highly efficient QDSCs. [ABSTRACT FROM AUTHOR]

To better understand the behavior of photogenerated charges in the composite photocatalyst interface is beneficial to the designing of effective photocatalyst for photocatalytic reaction. In our work, the separation and transfer process of photogenerated charges in NiO/TiO 2 nanotube arrays (NiO/TiO 2 NTAs) has been studied by surface photovoltage (SPV) spectroscopy and transient photovoltage (TPV) measurement. Through the experimental results analysis, we find that an interfacial electric field is formed at NiO/TiO 2 NTAs interface, which is attributed to the work function difference between NiO and TiO 2 NTAs. The photogenerated holes in TiO 2 can transfer to the NiO layer along the interface electric field under the ultraviolet irradiation. A large amount of photogenerated holes can be separated effectively and then prolonged the holes lifetime to participate in the photocatalytic oxidation reaction. The above results show that the favorable hole-collecting process of NiO in the surface of TiO 2 NTAs is the main factor being responsible for the increase the photocatalytic efficiency. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) and iron doped zinc oxide (Fe/ZnO) nanoflowers were successfully synthesized via a simple hydrothermal process. The samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman scattering, ultraviolet–visible (UV–vis) diffuse spectroscopy and scanning electron microscopy (SEM), and it was found that the dopant ions replaced some of the crystal lattice zinc ions, and furthermore, Fe 3+ and Fe 2+ ions coexist. Photocatalytic activities of the catalysts were assessed based on the degradation of rhodamine B (RhB) in aqueous solution under both UV and visible light irradiation ( λ > 420 nm), respectively. All Fe/ZnO samples showed enhanced photocatalytic activity under the irradiation of visible light. On the contrary, Fe/ZnO products displayed poorer performance than that of pure ZnO in the presence of UV light. This phenomenon can be attributed to the coexistence of Fe 3+ and Fe 2+ in the ZnO host. The photophysical mechanism of the UV and visible photocatalytic activity was investigated with the help of surface photovoltage (SPV) and PL measurements, respectively. The results indicated the influence of coexistence of Fe 3+ and Fe 2+ in ZnO host on the separation and transfer behavior of the photogenerated charges in the UV and visible regions, which are distinctly different: under the irradiation of UV light, the recombination of the photogenerated electrons and holes was promoted, whereas the separation and transfer of photogenerated electrons and holes was facilitated under the visible light irradiation. The detailed photocatalytic mechanism and the role of Fe on the photodegradation process are discussed. [ABSTRACT FROM AUTHOR]

Highlights: [•] The p-Cu2O/n-Cu2O homojunction film was prepared by electrodeposition. [•] We report the carrier kinetics of p-Cu2O/n-Cu2O homojunction film. [•] The interfacial electric field impacts the transfer direction of carrier. [•] The p-Cu2O/n-Cu2O homojunction film is used for sensing acetaldehyde. [ABSTRACT FROM AUTHOR]

The conducting character of the azo pigments of 4,4′-2-{N-[β-hydroxyl-γ-(p-methoxylanilino) naphthyl]}azodiphenyl (DCRL) and 4,4′-2-{N-[β-hydroxyl-γ-(m-nitroanilino)naphthyl]} azodiphenyl (DCBS) is examined by surface photovoltaic spectrum (SPS) and field induced surface photovoltaic spectrum (FISPS). The different responding behaviors to external fields indicate that DCRL and DCBS are an n-type and a p-type semiconductor, respectively. Electron withdrawing (donating) groups &z.sbnd;NO2 (&z.sbnd;OCH3) pull (push) the electrons from (to) central azo backbone and lower (boost up) the Fermi level thereby determine its conduction character. When they are incorporated into a p-type semiconducting film of titanyl-oxo-phthalocyanine (TiOPc), both TiOPc/DCRL and TiOPc/DCBS composites show surface photovoltaic signals significantly reduced in the magnitude in comparison with that of pure TiOPc, suggesting that the built-in field between TiOPc/electrode junction is sensitive to azo compounds. With respect to TiOPc/DCRL composite (20% DCRL by wt.), in near-IR spectral region, the FISPS demonstrates symmetric responses to both positive and negative fields, which are associated with local states. However no characteristic local state responses are observed in TiOPc/DCBS composite (20% DCBS by wt.). The formation of donor/acceptor system between p-type TiOPc and n-type DCRL is a reasonable ascription to the observed phenomenon. [Copyright &y& Elsevier]

The optimized 150Ti-Fe 2 O 3 /In 2 O 3 Z-scheme photoelectrode with the rapid interfacial hole trapped (∼ 8.96 ps) and long-lived charge separation states could achieve best PEC water splitting performance. [Display omitted] • The Ti-Fe2O3/In2O3 Z-scheme photoanodes were synthesized with the effective. • charge separation at the interface by adjusting the interfacial electric field. • The optimized 150Ti-Fe 2 O 3 /In 2 O 3 photoelectrode possesses the rapid. interfacial hole trapped (∼ 8.96 ps) and long-lived charge separation states. • The photocurrent density could achieve 2 mA/cm2 at 1.23 V vs. RHE, nearly 7 times higher than pure In 2 O 3. • The Z-scheme charges transfer behavior could be fully proved by femtosecond time-resolved absorption spectroscopy (fs-TAS). Exploiting interface-engineer of In 2 O 3 -based photoanode to achieve a higher charge separation efficiency could be regarded as a pivotal but challenging research in water splitting. Herein, the state-of-the-art Ti-Fe 2 O 3 /In 2 O 3 photoanodes with different Ti4+ doping concentrations are fabricated for exploring the interface-engineering effect on PEC performance. The optimized 150Ti-Fe 2 O 3 /In 2 O 3 photoelectrode with the rapid interfacial hole trapped (∼ 8.96 ps) and long-lived charge separation states could achieve excellent PEC performance by femtosecond time-resolved absorption spectroscopy (fs-TAS). As expected, it shows the highest photocurrent density of 2 mA/cm2 at 1.23 V vs. RHE, which is nearly 7 times higher compared with pure In 2 O 3. Moreover, the Z-scheme mechanism could be fully confirmed by femtosecond time-resolved absorption spectroscopy (fs-TAS) and in-situ double-beam detection strategy (AM 1.5 + 405 nm). This work provides an effective and feasible strategy on designing and regulating high-efficiency composite photoanode with Z-scheme transfer mechanism. [ABSTRACT FROM AUTHOR]

Abstract: We have successfully loaded C60 into a PPV precursor using CS2 and ethanol as mixed solvents and fabricated uniform PPV/C60 composite nanofibers by electrospinning for the first time. C60 was homogeneously distributed in nanofibers. The PL spectra analysis confirmed the formation of a composite and revealed the obvious fluorescent quenching comparing with pure PPV nanofibers. Countable electrospun composite nanofibers on a Au interdigitated electrode showed a fast and highly optoelectric response under 100mW/cm2 light irradiation by a Xe lamp. The results showed that photo induced charge transfer took place at the interface of PPV and C60 and suggested the great potential in the field of micro/nano organic optoelectric devices, especially in micro/nano organic photoswitches. [ABSTRACT FROM AUTHOR]