Hot carriers (HCs) and thermal effects, stemming from plasmon decays, are crucial for most plasmonic applications. However, quantifying these two effects remains extremely challenging due to the experimental difficulty in accurately measuring the temperature at reaction sites. Herein, we provide a novel strategy to disentangle HCs from photothermal effects based on the different traits of heat dissipation (long range) and HCs transport (short range), and quantitatively uncover the dominant and potential‐dependent role of photothermal effect by investigating the rapid‐ and slow‐response currents in plasmon‐mediated electrochemistry at nanostructured Ag electrode. Furthermore, the plasmoelectric surface potential is found to contribute to the rapid‐response currents, which is absent in the previous studies.

Platinum-based catalysts are widely used in hydrogen evolution reactions; however, their applications are restricted because of the cost-efficiency trade-off. Here, we present a thermodynamics-based design strategy for synthesizing an Al 73 Mn 7 Ru 20 (atomic %) metal catalyst via combinatorial magnetron co-sputtering. The new electrocatalyst is composed of ~2 nanometers of medium-entropy nanocrystals surrounded by ~2 nanometers of amorphous regions. The catalyst exhibits exceptional performance, similar to that of single-atom catalysts and better than that of nanocluster-based catalysts. We use aluminum rather than a noble metal as the principal element of the catalyst and ruthenium, which is cheaper than platinum, as the noble metal component. The design strategy provides an efficient route for the development of electrocatalysts for use in large-scale hydrogen production. Moreover, the superior hydrogen reaction evolution created by the synergistic effect of the nano-dual-phase structure is expected to guide the development of high-performance catalysts in other alloy systems.

Plasmon-mediated chemical reactions (PMCRs) possess desirable opportunities for manipulating the reaction outcomes due to the unique impact from surface plasmons. However, achieving PMCR product selectivity by tuning the light wavelength has rarely been demonstrated and the underlying mechanism of product selectivity remains elusive. This work studies the reaction mechanism of one classical type of PMCR, plasmon-aided reduction of p-nitrothiophenol (PNTP), and discovers that the reduction product of PNTP can be easily manipulated by adjusting the excitation light wavelength due to the different thermal and hot-electron effects induced by the different wavelengths. Specifically, the sole product of p,p′-dimercaptoazobenzene is obtained under 514 nm light due to the dominant thermal effect thus created, whereas p-aminothiophenol is more favorably produced under 785 nm light, which enables more efficient generation of hot electrons.

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Hot carriers (HCs) and thermal effects, stemming from plasmon decays, are crucial for most plasmonic applications. However, quantifying these two effects remains extremely challenging due to the experimental difficulty in accurately measuring the temperature at reaction sites. Herein, we provide a novel strategy to disentangle HCs from photothermal effects based on the different traits of heat dissipation (long range) and HCs transport (short range), and quantitatively uncover the dominant and potential-dependent role of photothermal effect by investigating the rapid-and slow-response currents in plasmon-mediated electrochemistry at nanostructured Ag electrode. Furthermore, the plasmoelectric surface potential is found to contribute to the rapid-response currents, which is absent in the previous studies.Mostplasmonicapplications,suchasphotothermaltherapy, photodetection, and plasmon-mediated chemical reactions (PMCRs), are closely associated with the nonradiative decays of plasmons where hot carriers (HCs, electrons well above and holes well below the Fermi level of metals) are generated (HC effect) and the local heating is induced (thermal effect). [1] To quantify these two effects is of paramount importance for designing and optimizing energy-efficient plasmonic devices. Recently, several attempts have been made for distinguishing these effects, giving conflicting conclusions. [2] In these studies, thermal effect was first identified by virtue of the temperature change recorded using a thermal camera, and the contribution of HCs was then deduced by subtracting the thermal effect from the overall plasmonic effects. Unfortunately, the accurate measurement of the surface temperature at the reaction sites remains an exceptionally difficulty task for current techniques, and even a small error may result in a completely different conclusion because the reaction rates are exponentially dependent on temperature. [3] Herein, to bypass this difficulty, the HCs and thermal contributions in plasmon-mediated electrochemistry at nanostructured Ag electrode were decoupled and quantified based on its photoelectrochemical behaviors, taking advantage of the very different transport distances of phonons and HCs as well as the high temporal resolution in photoelectrochemical measurement. The dominant and potential-dependent role of thermal effect were readily revealed by differentiating the rapid-(I RC , non-thermal effect) and slow-(I SC , thermal effect) response currents in their photocurrent profiles. In essence, the nonthermal processes were found to originate from populating O 2 antibonding orbital by hot electron under cathodic biases, or from the "plasmoelectric effects" under anodic biases. Furthermore, the ratio between I SC and I RC can be manipulated by adjusting the electrode potential, laser wavelength and intensity, pointing to a promising route to control the thermal and nonthermal contributions to PMCRs for achieving optimal reaction selectivity and yields.The plasmonic Ag electrodes that feature a surface consist...

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Water splitting through efficient catalysts represents an ultimate solution for carbon neutrality within 40 years. To achieve this goal, amorphous photocatalysts are noted for their promising performances. Among them, the best known is black titania (amorphous TiO x , x ≤ 2). However, despite a large number of studies on black titania, its color origin, structure−property relationship, and photocatalytic mechanism remain a topic of hot debate, largely due to the difficulty to calculate its precise electronic structure. Here, using ab initio molecular dynamics simulations, we report the precise electronic structures of black titania and further reveal the generic evolution pattern of the electronic structures of covalent compounds upon amorphization and reduction. An interesting "disproportionation-like" process resulting in metal clusters of Ti is discovered in heavily reduced amorphous titania, accompanied by oxygen vacancies in different energy states. This study elucidates the workings of amorphous catalysts and offers practical guidance for enhancing their performances.

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