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, Letnik:
69, Številka:
2
Journal Article
Recenzirano
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.
The development of Fe single‐atom catalysts (Fe SACs) with abundant, accessible Fe sites is a key step toward enhancing the efficiency of the oxygen reduction reaction (ORR) in proton exchange ...membrane fuel cells (PEMFCs). In this study, Zn4O(1,4‐benzenedicarboxylate)3 (MOF‐5), which has a 3D microporous cubic structure, is used as the precursor to prepare highly‐porous carbon (denoted as C‐MOF‐5) with an ultrahigh specific surface area (2751 m2 g–1) and high external surface area (1651 m2 g–1). C‐MOF‐5 is demonstrated as an effective carbon support to yield Fe SAC‐MOF‐5 with a large amount of accessible FeNx sites (2.35 wt%). Fe SAC‐MOF‐5 delivers a half‐wave potential of 0.83 V (vs RHE) in a 0.5 m H2SO4 electrolyte, and achieves a peak power density of 0.84 W cm–2 in a 0.2 MPa H2‐O2 PEMFC. This excellent performance originates from the ultrahigh specific surface area of C‐MOF‐5 for the formation of a high density of single Fe atoms, and high external surface area for the increased exposure of active sites. This work may inspire the rational design of metal single‐atom catalysts derived from a wider range of MOF precursors with ultrahigh specific area to improve the performance of the oxygen reduction reaction in PEMFCs.
A Fe single‐atom catalyst (Fe SAC‐MOF‐5) is successfully synthesized using MOF‐5 derived porous carbon (C‐MOF‐5) as a precursor. C‐MOF‐5 possesses an ultrahigh specific surface area to afford large amounts of FeNx sites, and a large external surface area to enable active sites to be fully accessible. Fe SAC‐MOF‐5 demonstrates superior oxygen reduction reaction activity and excellent performance in proton exchange membrane fuel cells.
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.
Private Set Intersection Cardinality (PSI-CA) is one of the most concerned issues with the protection of privacy, in which two parties jointly compute the intersection cardinality without revealing ...their respective private sets. There are important applications of PSI-CA in real society, e.g., strongly privacy-preserving data statistics in contact tracing for health authorities to fight the outbreaks of highly contagious diseases. In this paper, we present a novel quantum PSI-CA protocol, in which we adopt oblivious quantum key distribution, secure quantum summation and quantum counting algorithm. The proposed PSI-CA protocol not only ensures the approximatively perfect security but also achieves the linear communication complexity, i.e., <inline-formula> <tex-math notation="LaTeX">{O(N)} </tex-math></inline-formula>. Furthermore, we define a new privacy protection problem, i.e., Privacy-preserving Condition Query (PCQ), and provide an efficient solution to the PCQ problem based on the proposed quantum PSI-CA protocol. Finally, we verify the correctness and the feasibility of the proposed quantum PSI-CA protocol by circuit simulations in IBM Qiskit.
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