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- 摘要
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- 实验方案
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Perspective on construction of heterojunction photocatalysts and the complete utilization of photogenerated charge carriers
摘要： Semiconductor photocatalysis has received tremendous attention as a promising way for solving the worldwide energy and environment issues. Many efforts have been devoted to developing distinctive morphology and various semiconductor-based composite photocatalysts for enhancing photocatalytic activity in recent years. However, it is still a great challenge and imperative to profoundly understand the transfer mechanisms and to realize complete utilization of photoexcited charge carriers. This perspective for the first time highlights the inner impetus of the photogenerated charge carrier migration (band-band and Z-scheme transfers) over composite photocatalysts. The notion of relative p-n junction for photocatalysis and the corresponding design principle of Z-scheme photocatalysts are introduced first. Then, simultaneous utilization of photogenerated electrons and holes for photocatalytic selective redox syntheses in one reaction system is recommended. The proposed reaction systems have characteristics of the environmentally friendly, atom economy, synergistic effect and high efficiency. Finally, the challenges and opportunities of photocatalysis are outlined and a perspective is given. We hope that the perspective review could give an inspiration for the fundamental research and guide the research direction of photocatalysis.
关键词： Z-scheme,Inner impetus,Photocatalytic redox,Heterojunction photocatalyst,Relative p-n junction
更新于2025-09-19 17:15:36
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Hydrogen and Oxygen Evolution in a Membrane Photoreactor Using Suspended Nanosized Au/TiO2 and Au/CeO2
摘要： Photocatalysis combined with membrane technology could offer an enormous potential for power generation in a renewable and sustainable way. Herein, we describe the one-step hydrogen and oxygen evolution through a photocatalytic membrane reactor. Experimental tests were carried out by means of a two-compartment cell in which a modified Nafion membrane separated the oxygen and hydrogen evolution semi-cells, while iron ions permeating through the membrane acted as a redox mediator. Nanosized Au/TiO2 and Au/CeO2 were employed as suspended photocatalysts for hydrogen and oxygen generation, respectively. The influence of initial Fe3+ ion concentration, ranging from 5 to 20 mM, was investigated, and the best results in terms of hydrogen and oxygen evolution were registered by working with 5 mM Fe3+. The positive effect of gold on the overall water splitting was confirmed by comparing the photocatalytic results obtained with the modified/unmodified titania and ceria. Au-loading played a key role for controlling the photocatalytic activity, and the optimal percentage for hydrogen and oxygen generation was 0.25 wt%. Under irradiation with visible light, hydrogen and oxygen were produced in stoichiometric amounts. The crucial role of the couple Fe3+/Fe2+ and of the membrane on the performance of the overall photocatalytic system was found.
关键词： water splitting,photocatalytic membrane reactor,photocatalysis,Z-scheme
更新于2025-09-19 17:15:36
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Platform for molecular-material dual regulation: A direct Z-scheme MOF/COF heterojunction with enhanced visible-light photocatalytic activity
摘要： Series of novel metal-organic framework/covalent organic framework (MOF/COF) hybrid materials were constructed by encapsulating MOF with highly stable TTB-TTA (a COF synthesized from 4,4',4''-(1,3,5-triazine-2,4,6-triyl)tribenzaldehyde (TTB) and 4,4',4''-(1,3,5-triazine-2,4,6-triyl)trianiline (TTA)) layer, inheriting their merits of high crystallinity, large surface area, outstanding visible-light response and tunable band gaps. The introduction of NH2-MIL-125(Ti) into the hybrid materials could modulate their optical, electronic and redox properties, and promote the charge separation owing to the formation of heterojunction, thus resulting in an enhanced photocatalytic performance for organic pollutant decomposition. As such, NH2-MIL-125(Ti)/TTB-TTA composite has a much higher photodegradation kinetic of methyl orange (MO) which is over 9 and 2 times the rates of pure NH2-MIL-125(Ti) and TTB-TTA, respectively. This versatile molecular-material platform can achieve dual adjusting modes consisting of a COF molecular engineering and a MOF type screening strategy, which will be applicable to a wide range of fields.
关键词： metal-organic frameworks,covalent organic frameworks,heterogeneous photocatalysis,Z-scheme heterojunction,visible-light-driven
更新于2025-09-19 17:15:36
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Implementation of Metallic Vertical Interconnect Access in Hybrid Intercalated Graphene/Quantum Dot Photodetector for Improved Charge Collection
摘要： Performance improvement of heat recovery-based power generation (HRPG) systems puzzles researchers due to the implicitly coupled property. This contribution builds the heat current model of a HRPG system and applies the circuit principle to derive its heat transfer and conversion constraints. Then, derivation of the flow resistance balance equations describes the pressure distribution in circulation loop. Combining with the relations between fluid temperatures and pressures constructs the integrated system model. Based on the separation of linear topology equations and explicit nonlinear component equations from implicit nonlinear constraints using heat current model, this contribution introduces a fast and stable divide-and-conquer solution scheme, which solves linear equations in iterations and updates the iterative variables by substitutions. Finally, optimization of the fluid flow rates for the maximum net electricity generation under different working conditions shows the superiority of the heat current method over the commercial software Ebsilon. The optimized results show that a smaller mass flow rate of flue gas leads to lower optimal evaporation and condensation pressures, while the optimal dryness fraction of exhaust steam is almost unchanged. Besides, the constant backpressure operation strategy apparently deviates from the optima, and the maximum deviation reaches 8.6%.
关键词： Energy conservation,Heat recovery-based power generation,Solution scheme,Heat current model,Global optimization
更新于2025-09-19 17:13:59
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Hermitian second-order methods for excited electronic states: Unitary coupled cluster in comparison with algebraica??diagrammatic construction schemes
摘要： Employing an intermediate state representation (ISR) approach, Hermitian second-order methods for the calculation of electronic excitation energies are presented and compared in detail. These comprise the algebraic–diagrammatic construction scheme for the polarization propagator, a hybrid second-order ISR scheme based on traditional coupled-cluster theory as well as two similar approaches based on a unitary coupled-cluster (UCC) ansatz. Although in a strict perturbation-theoretical framework all prove to be identical, differences emerge when the corresponding converged cluster amplitudes are used and depending on how the similarity-transformed UCC Hamiltonian is evaluated. The resulting excitation energies, however, do not significantly differ for systems well described by means of perturbation theory.
关键词： unitary coupled-cluster,electronic excitation energies,intermediate state representation,perturbation theory,Hermitian second-order methods,algebraic–diagrammatic construction scheme
更新于2025-09-19 17:13:59
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An <i>in situ</i> assembled WO <sub/>3</sub> a??TiO <sub/>2</sub> vertical heterojunction for enhanced Z-scheme photocatalytic activity
摘要： The face-to-face contact of a vertical heterojunction is beneficial to charge interaction in photocatalysis. However, constructing a vertical heterojunction with uncompromised redox ability still remains a challenge. Herein, we report the successful synthesis of a WO3–TiO2 vertical heterojunction via establishing an internal electric field across the interface. Experimental investigation and computational simulations reveal that strong electric coupling occurs at the WO3–TiO2 interface forming an internal electric field. The internal electric field induces a Z-scheme charge-carrier transfer through the heterojunction under light irradiation, which leads to effective charge separation and maintains high reaction potentials of charge-carriers. The improved photocatalytic activity of the WO3–TiO2 heterojunction is proved by enhanced generation of reactive oxygen species and accelerated Escherichia coli (E. coli) disinfection. This study provides new insights into understanding and designing Z-scheme heterogeneous photocatalysts.
关键词： vertical heterojunction,Z-scheme,E. coli disinfection,WO3–TiO2,reactive oxygen species,photocatalysis
更新于2025-09-19 17:13:59
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An Efficient Quantum Sealed Bidding Auction Scheme Based on the Correlation of Genuine Five-Qubit Entangled State
摘要： In this paper, an efficient quantum sealed bidding auction scheme based on genuine five-qubit entangled state is proposed. The scheme utilizes the correlation of quantum entangled states to transmit bidding information. It can use an entangled state to transmit two bits of bidding information, which greatly improves the transmission efficiency. In order to avoid collusion between bidders and auctioneer, we introduce a semi-trusted third party Trent. His supervision during the whole auction process can help participants trust each other and reduce the possibility of internal attacks. Finally, the security of the scheme is proved, and the scheme is more economical and feasible.
关键词： Sealed bidding auction scheme,Quantum measurement,Five-qubit entangled state
更新于2025-09-19 17:13:59
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Numerical Study of the Discharge Spatial Characteristics Influence on the KrF Laser Generation
摘要： A very-large-scale integration capable of extracting motion features from moving images in real time has been developed employing row-parallel and pixel-parallel architectures based on the digital pixel sensor technology. Directional edge filtering of input images is carried out in row-parallel processing to minimize the chip real estate. To achieve a real-time response of the system, a fully pixel-parallel architecture has been explored in adaptive binarization of filtered images for essential feature extraction as well as in their temporal integration and derivative operations. As a result, self-speed-adaptive motion feature extraction has been established. The chip was designed and fabricated in a 65-nm CMOS technology and used to build an object detection system. Motion-sensitive target image localization was demonstrated as an illustrative example.
关键词： parallel architecture,digital pixel sensor (DPS),Block-readout scheme,motion feature extraction (MFE),vision chip
更新于2025-09-19 17:13:59
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Laser photoionisation selectivity of <sup>177</sup> Lu radionuclide for medical applications
摘要： We consider the selectivity obtained by laser photoionisation of the 177Lu radioisotope according to the three-stage 5d 6s2 2D3/2 – 5d 6s 6p 4F o 1/2 scheme from the viewpoint of the task of isolating the radionuclide for medical use. The selectivity attained through various photoionisation channels and the impact of multiphoton processes and the laser radiation spectrum on the photoionisation selectivity are investigated.
关键词： three-stage scheme,177Lu radionuclide,laser photoionisation
更新于2025-09-16 10:30:52
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[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Time-Division based Scheduling Scheme for Hybrid Optical/Electrical Data Center Network
摘要： the Past few years have witnessed the great development of Optical Circuit Switches (OCSes), which support high and dynamic bandwidth at low per-bit overhead in the data center network. Although OCSes deliver variety of attractive properties, the challenge still remains due to the unneglectable reconfiguration delay of OCSes. Previous OCS-based proposals amortize long reconfiguration overhead by reconfiguring OCSes at intervals of a few 100s of milliseconds, which inevitably incurs a mass of packets waiting during reconfiguration intervals, hence the degradation of network performance happens. In this paper, we propose an OCS-based scheduling scheme named Time-Division Scheduling (TDS), which groups OCSes and reconfigures different groups in sequential time slots, instead of periodically reconfiguring all OCSes. TDS diminishes the impact of the long reconfiguration delay with mere directly software modifications. We evaluate the performance of TDS via OMNET++. The experimental results show that TDS delivers significant performance enhancements in latency and benefits slightly on the throughput.
关键词： Optical Circuit Switch,Data Center Networks,Scheduling Scheme
更新于2025-09-16 10:30:52