A novel sensing hybrid-material of Au nanoparticles (Au NPs)-functionalized ZnO nanowires (Au-ZnO NWs) was successfully synthesized by a two-stage solution process. First, ZnO NWs were fabricated via a low-temperature one-pot hydrothermal method with SDSN introduced as a structure-directing agent. Afterward, the as-prepared ZnO NWs were used as supports to load Au NPs with small sizes via precipitating HAuCl4 aqueous solution with ammonia. The obtained samples were characterized by means of XRD, SEM, TEM and EDX. Both pristine and Au-ZnO NWs were practically applied as gas sensors to compare the effect of Au NPs on the sensing performances and the obtained results demonstrated that after functionalization by catalytic Au NPs, the hybrid sensor exhibited not only faster response and recovery speeds but also a higher response to benzene and toluene than the pristine ZnO sensor at 340 °C, especially showing high selectivity and long-term stability for low concentration toluene, which is rarely reported with this method, indicating its original sensor application in detecting benzene and toluene. To interpret the enhanced gas sensing mechanism, the strong spillover effect of the Au NPs and the increased Schottky barriers caused by the electronic interaction between Au NPs and ZnO NW support are believed to contribute to the improved sensor performance.

Functionalization of hydrogen‐bonded organic frameworks (HOFs) for specific applications has been a long‐lasting challenge in HOF materials. Here, an efficient way to integrate functional species in the HOF structure through constructing an anionic framework is presented. The obtained HOFs, taking PFC‐33 (PFC = porous materials from FJIRSM,CAS) as an example, integrate a porphyrin photosensitizer as a porous backbone and a commercial biocide as counterions in the structure. The permanent channels and the electrostatic interaction between the framework and the counterions provide PFC‐33 ion‐responsive biocide‐release behavior in various physiological environments, thus exhibiting synergistic photodynamic and chemical antimicrobial efficiency. The unbonded carboxyl groups residing on the HOF surface further allow for manipulating the interfacial interaction between the PFC‐33 and the polymer matrix for membrane fabrication. Therefore, a polyHOF membrane with high stability, desired flexibility, and good permeability is obtained, which demonstrates noticeable bacterial inhibition toward Escherichia coli. This study may shed light on the functionalization of HOF materials for broad application potentials.

A novel energy-balanced task-scheduling method is proposed that extends the lifespan of wireless sensor networks (WSNs) for collaborative target tracking using an unscented Kalman filter (UKF) algorithm. It is shown that the tracking accuracy is approximately proportional to the number of active sensor nodes participating in collaborative tracking. Excessive sensor nodes thus may be put to sleep mode to conserve energy provided there are a sufficient number of active sensor nodes. It is then shown that the lifespan of a WSN is dictated by the distribution of residue energy of sensor nodes. Specifically, we have shown that an energy-balanced WSN is likely to maximize its lifespan. As such, at each step of the tracking task, the head node must judiciously select active nodes from all sensors within the sensing range to minimize residue energy variations (energy balanced) while achieving desired tracking accuracy. This is formulated as a subset selection problem, which is shown to have a complexity that is NP-hard. Several energy-balanced scheduling for tracking (EBaST) heuristic algorithms are proposed to solve this problem with polynomial execution complexities. Extensive simulations have been conducted to compare EBaST against some stateof-the-art scheduling algorithms. It is observed that EBaST is more capable of significantly extending the WSNs lifespan than competing algorithms while delivering comparable or better tracking accuracy.

The changing trend of adsorption ability and the catalytic activity of Cu2O/g-C3N4 moved in the same direction.

Although many ionic metal–organic frameworks (MOFs) have been reported, little is known about how the charge of the skeleton affects the properties of the MOF materials. Herein we report how the chemical stability of MOFs can be substantially improved through embedding electrostatic interactions in structure. A MOF with a cationic skeleton is impervious to extremely acidic, oxidative, reductive, and high ionic strength conditions, such as 12 m HCl (301 days), aqua regia (86 days), H2O2 (30 days), and seawater (30 days), which is unprecedented for MOFs. DFT calculations suggested that steric hinderance and the repulsive interaction of the cationic framework toward positively charged species in microenvironments protects the vulnerable bonds in the structure. Diverse functionalities can be bestowed by substituting the counterions of the charged framework with identically charged functional species, which broadens the horizon in the design of MOFs adaptable to a demanding environment with specific functionalities.

Controllable synthesis of graphitic-C3N4 nanodots embedded in N, S co-doped hollow porous carbon via a double-solvent strategy for obtaining high performance of lithium–sulfur batteries.

A Brønsted acid-base bifunctional metal-organic framework (MOF) catalyst, PCN-700-AB [A = Brønsted acid site, TPDC-(COOH) 2 [(1,1′∶4′,1″terphenyl)-2,2″,4,4″-tetracarboxylic acid] and B = Brønsted basic site, BDC-NH 2 ], was designed precisely and synthesized successfully through sequential installation of Brønsted acid and base functionalities in a crystalline zirconium (Zr)-MOF. The installation underwent single-crystal-to-singlecrystal transformation throughout the process; hence, the structure of the bifunctional catalyst could be characterized accurately via single-crystal X-ray crystallography. The bifunctional MOF catalyst obtained exhibited excellent acid-base catalytic activity for a cascade of one-pot deacetalization-Knoevenagel condensation reaction. The work presented here could be considered as a promising solution to incorporate multifunctional components readily, especially the hostile aspects, into one MOF structure.

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