Defect-designed Mo-doped BiVO_(4)photoanode for efficient photoelectrochemical degradation of phenol

The monoclinic scheelite BiVO_(4)has impressive properties such as a narrow energy band gap,exceptional stability,and extended absorption in visible light,making it a suitable photoanode.Nevertheless,the BiVO_(4)material encounters challenges such as the high recombination rate of photogenerated electronhole pairs and poor photoelectron conductivity,which limits photocatalytic activity.To address this problem,we developed Mo-doped BiVO_(4)films on FTO substrates for photoelectrocatalytic degradation of phenol.When exposed to visible light,the Mo-BiVO_(4)film attained a 70%degradation of phenol in 120 min with a 1.2 V vs.Ag/AgCl bias—a 3.7 times improvement from pristine BiVO_(4).Mo-doping facilitates better migration and separation of electron-hole pairs and increases the concentration of photogenerated carriers,leading to an upward shift of the valence band potential direction,and an improvement in oxidation capacity.Furthermore,density-functional theory(DFT)calculations were used to explain how Modoping with BiVO_(4)improves the adsorption energy to phenol degradation intermediates,emphasizing its effectiveness in promoting phenol degradation.Therefore,with the inclusion of DFT calculations,this work provides a more comprehensive understanding of the mechanism underlying the enhancement of photocatalytic activity by Mo-doped BiVO_(4),which is crucial information for the further development of effective and efficient photoanodes.

Solid-state NMR study on sodium intercalation at low voltage window for Na_(3)V_(2)(PO_(4))_(3) as an anode

In-situ XRD,^(31)P NMR and ^(23)Na NMR were used to analyze the interaction behavior of Na_(3)V_(2)(PO_(4))_(3) at low voltage,and then a new intercalation model was proposed.During the transition from Na_(3)V_(2)(PO_(4))_(3) to Na_(4)V_(2)(PO_(4))_(3),Na ions insert into M1,M2 and M3 sites simultaneously.Afterwards,during the transition of Na_(4)V_(2)(PO_(4))_(3)to Na_(5)V_(2)(PO_(4))_(3),Na ions mainly insert into M3 site.

Cooperative fault detection and recovery in the GNSS positioning of mobile agent swarms based on relative distance measurements

Relative measurements are exploited to cooperatively detect and recover faults in the positioning of Mobile Agent(MA)Swarms(MASs).First,a network vertex fault detection method based on edge testing is proposed.For each edge,a property that has a functional relationship with the properties of its two vertices is measured and tested.Based on the edge testing results of the network,the maximum likelihood principle is used to identify the vertex fault sources.Second,an edge distance testing method based on the noncentral chi-square distribution is developed for detecting faults in the Global Navigation Satellite System(GNSS)positioning of MASs.Third,a recovery strategy for faults in the positioning of MASs based on distance measurement is provided.The effectiveness of the proposed methods is validated by a simulation case in which an MAS passes through a GNSS spoofing zone.The proposed methods are conducive to increasing the robustness of the positioning of MASs in complex environments.The main novelties include the following:(A)network vertex fault detection is based on concrete probability analysis rather than simple majority voting,and(B)the relation of detectability and recoverability of MAS positioning faults with the structure of the relative measurement network is first disclosed.