Search

Single metal atoms decorated on earth‐abundant transition‐metal‐based supports have attracted intensive attention toward oxygen evolution reaction (OER) due to their decent activity and low cost. However, further optimizing the catalytic performance is severely plagued by the limited active sites. Conventional optimization relies primarily on increasing the metal loading but is extremely difficult. Thus, it is imperative to go beyond the current design paradigms. Herein, it is reported that the anchored highly active single metal atoms can reinforce the electrochemical reconstruction of the supports and thus yield more substrate active sites. Consequently, increased amount of active sites and enhanced intrinsic activity can be readily realized simultaneously. Taking Ni2P4O12 decorated with single Ir atoms as a typical example, an extraordinary activity of η10 = 186 mV and η100 = 238 mV and robust stability up to 108 h are achieved. Mechanistic study uncovers that the reinforced reconstruction of Ni2P4O12 originates from the promoted PO43− leaching by single Ir atoms, which is an intrinsic feature of the supports to achieve such reinforcement. The proposed concept, decorating single metal atoms on supports featured by facile anion leaching, opens a new avenue to the design of practical electrocatalysts for efficient OER. [ABSTRACT FROM AUTHOR]

Recently, the bismuth‐rich strategy via increasing the bismuth content has been becoming one of the most appealing approaches to improve the photocatalytic performance of bismuth oxyhalides. However, insights into the mechanism behind the encouraging experiments are missing. Herein, we report the results of the theory‐led comprehensive picture of bismuth‐rich strategy in bismuth oxyhalide photocatalysts, selecting Bi5O7X (X = F, Cl, Br, I) as a prototype. First‐principle calculations revealed that the strategy enables good n‐type conductivity, large intrinsic internal electric field, high photoreduction ability and outstanding harvest of visible light, and particularly ranked the intrinsic activity of this family: Bi5O7F > Bi5O7I > Bi5O7Br > Bi5O7Cl. Designed experiments confirmed the theoretical predictions, and together, these results are expected to aid future development of advanced photocatalysts. [ABSTRACT FROM AUTHOR]

With rising CO2 emissions caused by the massive consumption of fossil fuels, it is highly desirable to develop strategies that adopt renewable energy to convert CO2 into value‐added chemical feedstocks. Over the past decades, photocatalytic reduction of CO2 using light energy has attracted considerable attention. However, the advanced photocatalysis techniques cannot exert their action where light is unavailable. Here, a method for CO2 reduction on basis of vibration‐driven piezoelectricity to yield a piezo‐electrocatalysis effect which requires mechanical vibration rather than light, is proposed. Under mild vibration and sacrificial agent‐free conditions, the piezoelectric BaTiO3 catalyst provides a suitable piezo‐potential to overcome the redox potential of CO2 and convert it into CO with a maximum yield of 63.3 µmol g−1, achieving a reactivity comparable to those of photocatalysts. The piezo‐electrocatalytic CO2 reduction reaction adds a new avenue in addition to the existing photocatalytic techniques by expanding the scope of energy utilization to promote carbon neutrality. [ABSTRACT FROM AUTHOR]

Highly efficient photocathode with onset potential beyond 0.6 V is very desirable in order to construct photoelectrochemical (PEC) device for stand‐alone overall water splitting. In this work, it is reported a nonfullerene PBDB‐T:ITIC bulk heterojunction (BHJ) based photocathode delivering unprecedented positive onset potential of 0.8 V and optimal photocurrent density of −11.7 mA cm−2 at 0 V in pH 1 solution. The yielded high ideal ratiometric power‐saved efficiency (Φsaved,ideal) of 4.1% is a record among the previous organic photocathodes. When the electrolyte pH moves to neutral, the Φsaved,ideal is still to be 3.2%, yet being twice more than the currently reported highest value. Pairing with TiOx, the hole transport layer of CuOx with more efficient charge carrier transportation and hole extraction ability excels MoO3 and NiOx, contributing to the highly efficient solar hydrogen production in both acidic and neutral solutions. Premixing the BHJ blend precursor with an anti‐oxidative agent is proved to be a beneficial strategy to improve the PEC stability by suppressing the photo‐oxidation degradation of organic polymer materials. Subsequently a conceptual PEC cell comprising of tandem CuOx/BHJ/TiOx/Pt photocathode and BiVO4/NiFeOx photoanode with a high solar‐to‐hydrogen efficiency up to 1.1% is fabricated in neutral solution without assistance of extra bias. [ABSTRACT FROM AUTHOR]