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[Display omitted] Non-precious metals have shown attractive catalytic prospects in hydrogen production from ammonia borane hydrolysis. However, the sluggish reaction kinetics in the hydrolysis process remains a challenge. Herein, P-bridged Fe-X-Co coupled sites in hollow carbon spheres (Fe-CoP@C) has been synthesized through in situ template solvothermal and subsequent surface-phosphorization. Benefiting from the optimized electronic structure induced by Fe doping to enhance the specific activity of Co sites, bimetallic synergy and hollow structure, the as-prepared Fe-CoP@C exhibits superior performances with a turnover frequency (TOF) of 183.5 min−1, and stability of over 5 cycles for ammonia borane hydrolysis, comparable to noble metal catalysts. Theoretical calculations reveal that the P-bridged Fe-X-Co coupled sites on the Fe-CoP@C catalyst surfaces is beneficial to adsorb reactant molecules and reduce their reaction barrier. This strategy of constructing hollow P-bridged bimetallic coupled sites may open new avenues for non-precious metal catalysis. [ABSTRACT FROM AUTHOR]

Anchoring of single-atom Pt2+ and Pt0 on the surface of Sb 2 S 3 NRs highly benefits to the formation of metal (Pt)-semiconductor (Sb 2 S 3) electric interaction, which synergistically improves the broadband light harvesting and promotes the Sb 2 S 3 -to-Pt electron transfer following inhibited photoexciton recombination kinetics and enhanced H proton adsorption capacity, resulting higher and more durable photoactivity for H 2 O-to-H 2 conversion. [Display omitted] • Single atomic Pt2+/Pt0 active sites were successfully anchored on the Sb 2 S 3 nanorods. • The metal (Pt)-semiconductor (Sb 2 S 3) electric interaction was formed. • The optimal composite catalyst possesses enhanced H proton adsorption capacity. • Higher and more durable photoactivity for H 2 O-to-H 2 conversion were achieved. • The mechanism of multisite cocatalysis for photoactivity improvement was elucidated. Single atomic metal (SAM) cocatalysis is a potential strategy to improve the performance of photocatalytic materials. However, the cocatalytic mechanism of SAM sites in different valence states is rarely reported. Herein, single atomic Pt2+/Pt0 active sites were anchored on Sb 2 S 3 nanorods to synergistically improve the photoactivity for hydrogen production under simulated sunlight. Experimental results and density functional theory calculations indicated that the coexistence of single atomic Pt2+/Pt0 sites synergistically improves the broadband light harvesting and promotes the Sb 2 S 3 -to-Pt electron transfer following inhibited photoexciton recombination kinetics and enhanced H proton adsorption capacity, resulting higher and more durable photoactivity for hydrogen production. Therefore, the optimal Sb 2 S 3 -Pt 0.9‰ composite catalyst achieved remarkably enhanced hydrogen evolution rate of 1.37 mmol∙g−1∙h−1 (about 105-fold greater of that of Sb 2 S 3 NRs) under faintly alkaline condition, and about 5.41 % of apparent quantum yield (AQY 700 nm) was achieved, which shows obvious superiority in hydrogen production by contrasting with the reported Sb 2 S 3 -based photocatalysts and conventional semiconductor photocatalytic materials modified with noble metals. This study elucidate a well-defined mechanism of multisite cocatalysis for photoactivity improvement. [ABSTRACT FROM AUTHOR]

A novel ternary photocatalyst Ni 3 S 4 @ZIS@C 3 N 5 with type II and Z-type heterojunctions was synthesized for the first time by hydrothermal and electrostatic self-assembly methods, effectively avoiding the thermal decomposition of C 3 N 5 during the synthesis of the complex. The best ternary catalyst Ni 3 S 4 @ZIS@C 3 N 5 is capable of achieving an optimal hydrogen evolution rate of 9750 mmol g−1 h−1, which is approximately 10.89 times as high as that of C 3 N 5 , indicating that the complex effectively enhanced the photocatalytic properties of the monomer. The coexistence of two types of heterojunctions in the complex effectively enhances photocatalytic performance, in which the monomer ZIS constructs type II scheme with Ni 3 S 4 and Z-type scheme with C 3 N 5 , respectively. The two heterojunctions complement each other and jointly promote the rapid electron transfer from Ni 3 S 4 and C 3 N 5 to the ZIS surface. In conclusion, the cooperation of the two heterojunctions efficiently facilitates the migration of photogenerated carriers, thus enhancing the photocatalytic hydrogen generation performance of Ni 3 S 4 @ZIS@C 3 N 5. • The ternary composite photocatalyst Ni 3 S 4 @ZIS@C 3 N 5 was successfully synthesized for the first time. • The thermal decomposition of C 3 N 5 was effectively avoided by electrostatic self-assembly. • The cooperation of type II and Z-type heterojunction enhanced the photocatalytic hydrogen production performance. [ABSTRACT FROM AUTHOR]

[Display omitted] The rational design and preparation of advanced electrocatalysts for the hydrogen evolution reaction (HER) under alkaline conditions is the key to achieving sustainable hydrogen production. Herein, a new type of nitrogen-doped porous carbon nanosheets (NPCN) loaded with platinum group metals (Pd, Pt or Ru) were prepared. The introduction of melamine not only realized the doping of N -species, but also optimized the morphology and surface functional groups of the prepared catalysts. The prepared Pd-NPCN, Pt-NPCN and Ru-NPCN with a metal loading of about 10 wt% showed outstanding HER activity (21, 9 and 11 mv at 10 mA cm−2 current density), small Tafel slopes (49, 30 and 30 mV dec−1) and good stability in 1.0 M KOH. In addition, the mechanism of the introduction of melamine to improve the catalytic performance of HER was also discussed. Therefore, this work provides promising alternatives to traditional Pt-based catalysts, and is instructive for the design of high-efficiency alkaline HER catalysts. [ABSTRACT FROM AUTHOR]

Plasma-catalytic WGS was upgraded under 150 °C low temperature and the underlying mechanisms were proposed by Experimental and theoretical results. [Display omitted] • Plasma-catalytic WGS reaction achieves 96% CO conversion at 150 °C. • In-situ experimental results reveal the participation of gaseous radicals. • DFT calculations propose a WGS reaction mechanism under plasma condition. • Microkinetic model clarify the enhancement by radicals and vibrational excitation. Low temperature WGS reaction is kinetically limited though it is thermodynamically favored. Herein, an outstanding synergistic effect between dielectric barrier discharge (DBD) plasma and non-precious CuO x /CeO 2 catalysts was observed to robustly accelerate the water gas shift (WGS) reaction at 150 °C (increase from 6% to 96% after plasma on). The apparent activation energy of the reaction was remarkablly diminished by plasma (69.6 to 15.0 kJ/mol). In-situ characterization experiments (e. g. OES and DRIFTS) revealed that the OH radicals generated by plasma-induced H 2 O dissociation was found to participate in the WGS reaction. In the furtherly study in DFT calculation and microkinetic modelling investigation, the OH radicals were proved to be one of the reasons for the giant increase in reaction rate. Besides, the vibrational excitation of reactants (e. g. CO) promoted by plasma could also reduce the reaction barriers of some crucial elementary reactions, thus accelerating the reaction rate. [ABSTRACT FROM AUTHOR]

[Display omitted] Solar-driven photocatalytic H 2 evolution could tackle the issue of fossil fuels-triggered greenhouse gas emission with sustainable clean energy. However, splitting water into hydrogen with high performance by a single semiconductor is challenging because of the poor charge separation efficiency. Herein, a novel ternary Cu@TiO 2 -Cu 2 O hybrid photocatalyst with multiple charge transfer channels has been designed for efficient solar-to-hydrogen evolution. Indeed, the ternary Cu@TiO 2 -Cu 2 O hybrid by coupling Cu@TiO 2 with Cu 2 O nanoparticles shows highly-efficient photocatalytic hydrogen generation with rate of 12000.6 μmol·g−1·h−1, which is 4.4, 2.1, and 1.9 times higher than the pure TiO 2 (2728.8 μmol·g−1·h−1), binary Cu@TiO 2 (5595.5 μmol·g−1·h−1), and TiO 2 -Cu 2 O (6076.8 μmol·g−1·h−1) composite, respectively. In such a Cu@TiO 2 -Cu 2 O hybrid, the formed internal electric field in the TiO 2 -Cu 2 O p-n junction allows the electrons in Cu 2 O to migrate to TiO 2 , while the electrons in the CB of TiO 2 could flow into Cu via the Schottky junction at the Cu@TiO 2 interface. In this regard, a multiple charge transfer is achieved between the Cu@TiO 2 and Cu 2 O, which facilitates promoted charge separation and results in the construction of electron-accumulated center (Cu) and hole-enriched surface (Cu 2 O). This p-n/Schottky junctions with steered charge transfer assists the hydrogen production upon the Cu@TiO 2 -Cu 2 O ternary photocatalyst. [ABSTRACT FROM AUTHOR]