With the ambition of solving the challenges of the shortage of fossil fuels and their associated environmental pollution, visible‐light‐driven splitting of water into hydrogen and oxygen using ...semiconductor photocatalysts has emerged as a promising technology to provide environmentally friendly energy vectors. Among the current library of developed photocatalysts, organic conjugated polymers present unique advantages of sufficient light‐absorption efficiency, excellent stability, tunable electronic properties, and economic applicability. As a class of rising photocatalysts, organic conjugated polymers offer high flexibility in tuning the framework of the backbone and porosity to fulfill the requirements for photocatalytic applications. In the past decade, significant progress has been made in visible‐light‐driven water splitting employing organic conjugated polymers. The recent development of the structural design principles of organic conjugated polymers (including linear, crosslinked, and supramolecular self‐assembled polymers) toward efficient photocatalytic hydrogen evolution, oxygen evolution, and overall water splitting is described, thus providing a comprehensive reference for the field. Finally, current challenges and perspectives are also discussed.
Molecular design strategies of various conjugated polymers for photocatalytic water splitting are reviewed. The structure–property relationships between functional groups, building blocks, and photocatalytic water splitting in a variety of conjugated polymers are explored. Furthermore, key factors that contribute to a highly efficient polymer photocatalyst in visible‐light‐driven water splitting are outlined.
A sealed-bid auction is an essential tool for trading commodities in modern society. However, the non-winning bidders in previously proposed sealed-bid auction schemes lack privacy protection. In ...this paper, we define a sealed-bid auction with strong privacy protection, which can protect the privacy of all non-winning bidders. In order to fulfil the task, we first present a quantum secret sharing protocol and a secure quantum summation protocol and then design their corresponding quantum circuits, where the security of the latter is guaranteed by the former, while the former is information-theoretically secure. We further present a quantum seal-bid auction (QSA) scheme with strong privacy protection based on the designed quantum protocols. In our QSA scheme, each bidder first encodes a private vector by his private bid and public agreement information, and then all bidders jointly compute the summations of their respective private vectors without a trusted third party. Finally, we verify the correctness and the feasibility of the proposed QSA scheme by circuit simulations in IBM Qiskit.
In this letter, we systematically analyze the parity properties about Bell states, Pauli operators and Bell measurements, which are described as four interesting and flexible equations. Furthermore, ...we investigate their applications in fields of secure multiparty computations, and especially present a novel secret sharing protocol with anonymous authentication based on these equations, which can guarantee the unconditional security of the proposed protocol.
Anonymous Quantum Sealed-Bid Auction Shi, Run-Hua
IEEE transactions on circuits and systems. II, Express briefs,
02/2022, Volume:
69, Issue:
2
Journal Article
Peer reviewed
In this brief, we present a novel quantum protocol for sealed-bid auction and design the corresponding quantum circuits. In the proposed protocol, we introduce two auctioneers to ensure that they can ...supervise each other, where one is a classical auctioneer, and the other is a quantum auctioneer. Furthermore, we turn sealed-bid auction into secure multiparty summation by employing the Chinese Remainder Theorem to achieve the anonymity. Compared with the related protocols, the proposed protocol can meet more security properties, e.g., anonymity, fairness, verifiability, secrecy and non-repudiation.
In this brief, we present a novel quantum protocol for Multiparty Privacy Set Intersection Cardinality (MPSI-CA) and design the corresponding quantum circuits. The proposed protocol demonstrates two ...primary aspects of quantum advantage: the parallelism of quantum computing and the randomness of quantum measurement. Compared with the classical related protocols, the proposed MPSI-CA protocol can ensure higher security (i.e., unconditional security) and achieve better communication complexity (i.e., <inline-formula> <tex-math notation="LaTeX">{O}({t}^{2}) </tex-math></inline-formula>).
Herein, this work constructs a three-dimensional porous graphitic carbon nitride assembled by highly crystalline and ultrathin nanosheets (3D g-C3N4 NS). 3D g-C3N4 NS could directly split pure water ...into H2 and O2 with high evolution rate up to 101.4 and 49.1 μmol g−1 h−1 under visible light, respectively, approximately 11.8 and 5.1 times higher than bulk g-C3N4 and g-C3N4 NS. Besides, it achieves a notable apparent quantum yield of 1.4% at 420 nm, significantly superior to previously reported Pt/g-C3N4. The efficient activity of 3D g-C3N4 NS is mainly attributed to its 3D interconnected open-framework, assembled by highly crystalline ultrathin nanosheet unit, provides a pathway for faster charge carrier transport. Moreover, benefitting from its 3D structure for preventing agglomeration of nanosheets, 3D g-C3N4 NS is stable for more than 100 h of overall water splitting reaction.
Three-dimensional porous g-C3N4 assembled by highly crystalline and ultrathin nanosheets is successfully constructed, and could efficiently split pure water into H2 and O2 with a notable quantum yield as high as 1.4% at 420 nm. Besides, it still remains stable for more than 100 h of overall water splitting reaction. Display omitted
•Three-dimensional porous g-C3N4 nanosheets (3D U-C3N4 NS) assembled by ultrathin nanosheets was successfully fabricated.•3D U-C3N4 NS could directly split pure water into H2 and O2 with quite high evolution rate under visible light.•3D U-C3N4 NS achieved a notable quantum yield of 1.4% at 420 nm, significantly superior to previously reported Pt/g-C3N4.•3D U-C3N4 NS could still remain stable for more than 100 h of overall water splitting reaction.
Sealed-bid auction is an important tool in modern economic especially concerned with networks. However, the bidders still lack the privacy protection in previously proposed sealed-bid auction ...schemes. In this paper, we focus on how to further protect the privacy of the bidders, especially the non-winning bidders. We first give a new privacy-preserving model of sealed-bid auction and then present a quantum sealed-bid auction scheme with stronger privacy protection. Our proposed scheme takes a general state in N-dimensional Hilbert space as the message carrier, in which each bidder privately marks his bid in an anonymous way, and further utilizes Grover's search algorithm to find the current highest bid. By O(lnn) iterations, it can get the highest bid finally. Compared with any classical scheme in theory, our proposed quantum scheme gets the lower communication complexity.
There is interest in metal single atom catalysts due to their remarkable activity and stability. However, the synthesis of metal single atom catalysts remains somewhat ad hoc, with no universal ...strategy yet reported that allows their generic synthesis. Herein, we report a universal synthetic strategy that allows the synthesis of transition metal single atom catalysts containing Cr, Mn, Fe, Co, Ni, Cu, Zn, Ru, Pt or combinations thereof. Aberration-corrected high-angle annular dark-field scanning transmission electron microscopy and extended X-ray absorption fine structure spectroscopy confirm that the transition metal atoms are uniformly dispersed over a carbon black support. The introduced synthetic method allows the production of carbon-supported metal single atom catalysts in large quantities (>1 kg scale) with high metal loadings. A Ni single atom catalyst exhibits outstanding activity for electrochemical reduction of carbon dioxide to carbon monoxide, achieving a 98.9% Faradaic efficiency at -1.2 V.
Recently, heterogeneous photocatalysts have achieved much interest on account of their great potential applications in resolving many tough energy and environmental troubles around the world through ...an ecologically sustainable way. Heterogeneous nanocomposites composed of graphitic carbon nitride (g‐C3N4) and carbon dots (CDs) possess broad spectrum absorption, appropriate electronic band structures, rapid carrier mobility, abundant reserves, excellent chemical stability, and facile synthesis methods, which make them promising composite photocatalysts for suitable applications such as photocatalytic solar fuels production and contaminant decomposition. With the rapid development in photocatalysis by hybridization of g‐C3N4 and CDs, a systematic summary and prospection of performance improvement are urgent and meaningful. This review first focuses on various kinds of effectively synthetic methods of composites. Following, the strategies available for enhanced performance, including morphology optimization, spectral absorption improvement, ternary or quaternary composition hybrid, lateral or vertical heterostructures construction, heteroatom doping, and so forth, are fully discussed. Then, the applications mainly in efficient photocatalytic hydrogen generation, photocatalytic carbon dioxide reduction, and organic pollutants degradation are systematically demonstrated. Finally, the remaining issues and prospect of further development are proposed as some kind of guidance for powerful combination of g‐C3N4 and CDs with high efficiency to photocatalysis.
This review summarizes the recent progress of heterogeneous photocatalysts of g‐C3N4/carbon dot (CD)‐based nanocomposites and their applications mainly in efficient catalytic hydrogen generation, photocatalytic carbon dioxide reduction, and organic pollutants degradation. Finally, the challenges and opportunities for g‐C3N4/CD‐based photocatalysts are critically discussed to offer insight of this field.
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In recent years, two-dimensional (2D) semiconductor photocatalysts have been widely applied in water splitting, CO2 reduction, N2 fixation, as well as many other important ...photoreactions. Photocatalysts in the form of 2D nanosheet possess many inherent advantages over traditional 3D nanopowder photocatalysts, including improved light absorption characteristics, shorter electron and hole migration paths to the photocatalysts’ surface (thus minimizing undesirable electron-hole pair recombination), and abundant surface defects which allow band gap modulation and facilitate charge transfer from the semiconductor to adsorbates. When synergistically exploited and optimized, these advantages can impart 2D photocatalysts with remarkable activities relative to their 3D counterparts. Accordingly, a wide range of experimental approaches is now being explored for the synthesis of 2D photocatalysts, with computational methods increasingly being used for identification of promising new 2D photocatalytic materials. Herein, we critically review recent literatures related to 2D photocatalyst development and design. Particular emphasis is placed on 2D photocatalyst synthesis and the importance of computational studies for the fundamental understanding of 2D photocatalyst electronic structure, band gap structure, charge carrier mobility and reaction pathways. We also explore the practical challenges of using 2D photocatalysts, such as their difficulty to synthesize in large quantity and also their characterization. The overarching aim of this review is to provide a snapshot of recent work targeting high-performance 2D photocatalysts for efficient solar energy conversion, thus laying a firm base for future advancements in this rapidly expanding area of photocatalysis research.
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