Optimal metal domain size for photocatalysis with hybrid semiconductor-metal nanorods

Semiconductor-metal hybrid nanostructures offer a highly controllable platform for light-induced charge separation, with direct relevance for their implementation in photocatalysis. Advances in the synthesis allow for control over the size, shape and morphology, providing tunability of the optical and electronic properties. A critical determining factor of the photocatalytic cycle is the metal domain characteristics and in particular its size, a subject that lacks deep understanding. Here, using a well-defined model system of cadmium sulfide-gold nanorods, we address the effect of the gold tip size on the photocatalytic function, including the charge transfer dynamics and hydrogen production efficiency. A combination of transient absorption, hydrogen evolution kinetics and theoretical modelling reveal a non-monotonic behaviour with size of the gold tip, leading to an optimal metal domain size for the most efficient photocatalysis. We show that this results from the size-dependent interplay of the metal domain charging, the relative band-alignments, and the resulting kinetics

Charge Carrier Dynamics in Photocatalytic Hybrid Semiconductor-Metal Nanorods: Crossover from Auger Recombination to Charge Transfer

Hybrid semiconductor-metal nanoparticles (HNPs) manifest unique, synergistic electronic and optical properties as a result of combining semiconductor and metal physics via a controlled interface. These structures can exhibit spatial charge separation across the semiconductor-metal junction upon light absorption, enabling their use as photocatalysts. The combination of the photocatalytic activity of the metal domain with the ability to generate and accommodate multiple excitons in the semiconducting domain can lead to improved photocatalytic performance because injecting multiple charge carriers into the active catalytic sites can increase the quantum yield. Herein, we show a significant metal domain size dependence of the charge carrier dynamics as well as the photocatalytic hydrogen generation efficiencies under nonlinear excitation conditions. An understanding of this size dependence allows one to control the charge carrier dynamics following the absorption of light. Using a model hybrid semiconductor-metal CdS-Au nanorod system and combining transient absorption and hydrogen evolution kinetics, we reveal faster and more efficient charge separation and transfer under multiexciton excitation conditions for large metal domains compared to small ones. Theoretical modeling uncovers a competition between the kinetics of Auger recombination and charge separation. A crossover in the dominant process from Auger recombination to charge separation as the metal domain size increases allows for effective multiexciton dissociation and harvesting in large metal domain HNPs. This was also found to lead to relative improvement of their photocatalytic activity under nonlinear excitation conditions

Time-to-Sell of New Green Housing

This research explores the time-to-sell (TTS) of green real estate. We employ data on primary market transactions in six newly developed multi-story condominiums—of which three are green and three are conventionally built—located in a single neighborhood of Netanya, Israel. We find that, after addressing the potential endogeneity between unit TTS and price, the average TTS of units in green, as compared to conventional, structures is significantly shorter. Considering developers' financing cost, this shorter TTS is equivalent to an indirect price premium of 1%–5%. We also find that whenever the indirect green premium associated with TTS decreases, the green quality-adjusted price premium increases. Thus, considering both price and TTS, we estimate a total green price premium of about 5%

The local cost of terror: Effects of the second Palestinian Intifada on Jerusalem house prices

This research presents new findings on the economic cost of terror. To that end, we provide evidence of changes in house prices in the Gilo neighborhood of Jerusalem in the wake of the 2000 Second Palestinian Intifada. During that period, Gilo suffered from sporadic and ongoing gunfire from the neighboring Palestinian village of Beit Jala. Our sample includes 555 housing transactions from the Gilo neighborhood of Jerusalem over the 1997-2008 period. Results of VAR estimation indicate that shooting events result in a lagged 12% reduction in Gilo house values. However, as evidenced in the impulse response functions, those effects are largely reversed within 18 months of the terror event. Difference-in-difference analysis of the micro-data permits further assessment of the neighborhood spatial incidence of terror. Results indicate an average quality-adjusted house price decline of about 10% among "frontline" relative to "non-frontline" dwellings in Gilo in the aftermath of the outbreak of hostilities; moreover, much of that effect persisted some five years subsequent to the cessation of violence. Research findings suggest substantial residential property value effects of terrorism as incurred by households living in conflict areas. Those same households--like many others--would be the direct beneficiaries of conflict resolution.Terror House prices Palestinian-Israeli conflict

Optimal metal domain size for photocatalysis with hybrid semiconductor-metal nanorods.

Semiconductor-metal hybrid nanostructures offer a highly controllable platform for light-induced charge separation, with direct relevance for their implementation in photocatalysis. Advances in the synthesis allow for control over the size, shape and morphology, providing tunability of the optical and electronic properties. A critical determining factor of the photocatalytic cycle is the metal domain characteristics and in particular its size, a subject that lacks deep understanding. Here, using a well-defined model system of cadmium sulfide-gold nanorods, we address the effect of the gold tip size on the photocatalytic function, including the charge transfer dynamics and hydrogen production efficiency. A combination of transient absorption, hydrogen evolution kinetics and theoretical modelling reveal a non-monotonic behaviour with size of the gold tip, leading to an optimal metal domain size for the most efficient photocatalysis. We show that this results from the size-dependent interplay of the metal domain charging, the relative band-alignments, and the resulting kinetics