Triggering in-plane defect cluster on MoS_(2) for accelerated dinitrogen electroreduction to ammonia

Electrochemical nitrogen reduction reaction (eNRR) is an alternative promising manner for sustainable N2 fixation with low-emission. The major challenge for developing an efficient electrocatalyst is the cleaving of the stable Ntriple bondN triple bonds. Herein, we design a new MoS_(2) with in-plane defect cluster through a bottom-up approach for the first time, where the defect cluster is composed of three adjacent S vacancies. The well-defined in-plane defect clusters could contribute to the strong chemical adsorption and activation towards inert nitrogen, achieving an excellent eNRR performance with an ammonia yield rate of 43.4 ± 3 μg h^(−1) mgcat.^(−1) and a Faradaic efficiency of 16.8 ± 2% at −0.3 V (vs. RHE). The performance is much higher than that of MoS_(2) with the edge defect. Isotopic labeling confirms that N atoms of produced NH4+ originate from N2. Furthermore, the in-plane defect clusters realized the alternate hydrogenation of nitrogen in a side-on way to synthesize ammonia. This work provides a prospecting strategy for fine-tuning in-plane defects in a catalyst, and also promotes the progress of eNRR.

Rationally designed ultrathin Ni(OH)_(2)/titanate nanosheet heterostructure for photocatalytic CO_(2) reduction

Dye-sensitized photocatalysis has been extensively studied for photocatalytic solar energy conversion due to the advantage in capturing long-wavelength photons with a high absorption coefficient.The rational integration of photosensitizer with semiconductor and cocatalyst to collaboratively operate in one system is highly desired.Here,we fabricate a Ni(OH)_(2)-loaded titanate nanosheet(Ni(OH)_(2)/H_(2)Ti_(6)O_(13))composite for high-performance dye-sensitized photocatalytic CO_(2) reduction.The ultrathin H_(2)Ti_(6)O_(13) nanosheets with negative surface charge provide an excellent support to anchor the dye photosensitizer,while the loaded Ni(OH)2 serves as an adsorbent of CO_(2) and electron sink of photoelectrons.As such,the photoelectrons derived from the[Ru(bpy)3]Cl_(2) sensitizer can be targeted transfer to the Ni(OH)_(2) active sites via the H_(2) Ti_(6)O_(13) nanosheets linker.A high CO production rate of 1801μmol g^(-1) h^(-1) is obtained over the optimal Ni(OH)_(2)/H_(2)Ti_(6)O_(13),while the pure H_(2)Ti_(6)O_(13) shows significantly lower CO_(2) reduction performance.The work is anticipated to trigger more research attention on the rational design and synthesis of earth-abundant transition metal-based cocatalysts decorated on ultrathin 2D platforms for artificially photocatalytic CO_(2) reduction.