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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]

There are Type-II, S-Scheme, and Type-I heterojunctions in 4-Methyl-5-vinylthiazole (MVTh) modified Ni-MOF/g-C 3 N 4 /CdS. The aforementioned three heterojunctions form a closed-loop path for electron migration, and MVTh can accelerate the electron migration within the closed-loop path by facilitating the electron migration within Ni-MOF. The photocatalytic H 2 evolution rate of Ni-MOF/g-C 3 N 4 /MVTh/CdS is up to 17.844 mmol·g−1·h−1 without precious cocatalysts. [Display omitted] • We pioneered the use of Ni-MOF (BTC) in the photocatalytic hydrogen production. • 4-Methyl-5-vinyl thiazole can drive the directional electron transfer in Ni-MOF (BTC). • A triangular closed-loop path for electron transport was first designed. • The H 2 production rate is up to 17.844 mmol·g−1·h−1 without precious cocatalysts. The construction of heterojunction systems is an effective way to efficiently generate hydrogen by water photolysis. In this work, Ni-MOF (trimesic acid, (BTC)) and g-C 3 N 4 (denoted as CN) were combined, and then Ni-MOF/CN was modified by 4-Methyl-5-vinyl thiazole (denoted as MVTh). Finally, CdS was loaded on the surface of Ni-MOF/CN/MVTh to prepare the photocatalyst Ni-MOF/g-C 3 N 4 /MVTh/CdS (denoted as Ni/CN/M/Cd) with a triangular closed-loop path heterojunction for the first time. As a photocatalyst without precious metal cocatalysts, Ni/CN/M/Cd displayed high H 2 evolution (17.844 mmol·g−1·h−1) under an optimum CdS loading of 40 wt%. The H 2 evolution rate was approximately 79 times that of Ni-MOF/CN and exceeded those of almost all catalysts based on MOF/CN in the literature. The triangular closed-loop heterojunction formed between Ni-MOF, g-C 3 N 4 , and CdS could realize the directional migration of photocarriers and significantly diminished the transfer resistance of carriers. The Ni2+ in Ni-MOF provided many cocatalytic sites for H 2 evolution via g-C 3 N 4 and CdS. Furthermore, charge carrier separation in Ni-MOF/CN/CdS improved after the innovative addition of MVTh. This study provides a reference for the construction of a closed-loop heterojunction system without precious metal cocatalysts. [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] • PtRu catalysts composed of Pt and RuO 2 are synthesized via cyclic electrodeposition. • PtRu catalyst shows unprecedented performance for ECH of phenol to cyclohexanol. • PtRu catalyst possesses outstanding reusability in acidic electrolyte. • The activation of phenol is observed via in situ Raman spectroscopy. • The direct reduction mechanism with proton-coupled electron transfer is proposed. Electrocatalytic hydrogenation (ECH) of phenol has been recognized as a promising route towards facile and green production of cyclohexanol. However, the practical application is hindered by product selectivity and catalyst durability. Herein, a series of PtRu electrocatalysts composed of metallic Pt0 and RuO 2 species are in situ fabricated on carbon paper via cyclic electrodeposition, showing outstanding activity and stability for ECH of phenol. At ambient temperature and a current density of 10 mA cm−2, the optimal Pt3Ru3 catalyst achieves a 100 % selectivity to cyclohexanol at a 100 % conversion of phenol in 0.1 M H 2 SO 4. At 100 mA cm−2, Pt3Ru3 achieves an outstanding faradaic efficiency of ∼87 % and a cyclohexanol production of 52.6 mg cm−2 h−1. Two parallel ECH pathways from phenol to cyclohexanol are identified. In situ Raman spectroscopy and kinetic study reveal that phenol could be hydrogenated over Pt3Ru3 in acidic electrolyte via proton-coupled electron transfer with the destruction of conjugated π bond of aromatic ring. This work offers an effective approach for facile construction of durable electrode material and an efficient electrochemical strategy for phenol hydrogenation. [ABSTRACT FROM AUTHOR]

Single-atomic gold decorated CdS nanocatalyst for atom transfer radical addition of alkenes under blue-LED light. [Display omitted] • The Au SASs decorated CdS nanocatalyst was synthesized via a photoreduction strategy. • The host (CdS)-guest (Au) electron transfer mechanism was formed on this nanocatalyst. • ATRA reactions of alkenes can be achieved in high yields under blue-LED-induction. • The excellent selectivity is presented on this nanocatalyst. Atom transfer radical addition (ATRA) is commonly applied to introduce perfluoroalkyl groups into organic molecules, but it often suffers from harsh reaction condition, poor yield and expensive catalyst usage for practical application. Light-induced ATRA reaction is of great significance due to its merits of mild reaction condition and easy operation, but it is generally difficult to achieve high yield because of the lack of ideal photosensitizers. Herein, an Au single-atom sites (SASs) decorated hexagonal cadmium sulfide (CdS) nanocatalyst (Cat CdS-Au) was synthesized to catalyze ATRA reaction under mild blue-LED-induction. As a result, the synergetic effect of CdS-Au interaction enhanced the optical properties and promoted the host (CdS)-guest (Au) electron transfer, leading to high ATRA yields (88–98%) and excellent selectivity even choosing different alkene substrates, which is remarkably superior over existing reaction systems (60–90% yields) ever reported in literatures. The present work sheds light on realizing high ATRA reaction yield via a green and high-efficient synthetic strategy. [ABSTRACT FROM AUTHOR]

The humic substances (HS) - mediated electron transfer process is of great significance to the reduction and degradation of pollutants and the improvement of soil quality. Different soil conditions lead to different characteristics of HS, resulting in differences in the electron transfer capacity (ETC) of HS. It is unclear how the environmental conditions in soil affect the ETC by affecting on HS. In this study, the response relationship of soil microenvironment, HS and ETC has been studied. The results show that the ETC follows the descending order of: Langshan > Nanchang > Anqing > Beijing > Guilin. There were significant differences in ETC in soil HS in different regions. There were significant differences in electron-donating capacity (EDC) in soil HS in different regions and depths. EDC in soil was higher than electron-accepting capacity (EAC), and on average, are 22.4 times higher than the EAC. The HS components of soils in different regions are different. The most significant differences were in tyrosine-like substances and soluble microbial by-products (SMPs). The five components of the soil HS from Langshan were the most different from those in other regions. There were differences in SMPs and humic-like substances in soils of different depths in Anqing and Guilin. ETC can be affected by the composition of HS components in different regions. The composition of HS at different soil depths in the same regions had little effect on ETC. SMPs can promote ETC and EDC, and tyrosine-like substance can promote EDC. Moisture content, pH and TOC are the main factors affecting the composition of HS components. This results can provide a research basis for the sustainable and safe utilization of agricultural soil. [ABSTRACT FROM AUTHOR]