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To achieve low-cost photocatalytic hydrogen (H 2) production, it is necessary to develop low-priced transition metal co-catalysts to replace the roles of noble metals for photocatalytic H 2 evolution. Herein, a co-catalyst of Mo-doped CoS x (Mo-CoS x) was synthesized by using the hydrothermal procedure, then attached to g-C 3 N 4 to construct a composite photocatalyst. As a co-catalyst, Mo-CoS x can work as an electron acceptor, it is utilized to receive electrons generated by g-C 3 N 4 photocatalyst on the surface of the catalyst, and inhibit the recombination of those electrons, thus showing enhanced charge transfer ability as well as reduction ability. The optimized Mo-CoS x /g-C 3 N 4 delivered a prominent photocatalytic H 2 evolution rate of 2062.4 μmol h−1 g−1, which was ∼193 times higher than g-C 3 N 4. Its AQE at 400 nm and 420 nm were 11.05% and 6.83%, respectively. This work provides a novel non-precious metal co-catalyst/g-C 3 N 4 photocatalyst that is expected to be an acceptable cost route to solar energy conversion. A co-catalyst of Mo-doped CoS x (Mo-CoS x) was synthesized and used to promote the charge separation and reduce the energy barrier for proton reduction. As expected, the photocatalytic H 2 evolution rate of optimal Mo-CoS x /g-C 3 N 4 is 2062.4 μmol h−1 g−1, which is 193-fold compared with pristine g-C 3 N 4. [Display omitted] • A co-catalyst of Mo-doped CoS x (Mo-CoS x) was synthesized by using hydrothermal procedure. • An efficient Mo-CoS x /g-C 3 N 4 hetorojunction was designed for photocatalytic hydrogen evolution. • Mo-CoS x promoted the charge separation and reduced the energy barrier for proton reduction. [ABSTRACT FROM AUTHOR]

A metal coordination supramolecule constructed by 1,2,3-triazopyridine derivatives (PYTA) coordinated Pt(II) or Pd(II) can be worked as a cocatalyst to boost photocatalytic hydrogen evolution. [Display omitted] • 1,2,3-triazopyridine derivatives(PYTA) coordinated Pt(II) or Pd(II) supramolecular is constructed. • PYTA-Pd(II) and PYTA-Pt(II) are used as co-catalysts for photocatalytic H 2 evolution. • PYTA-Pd(II) and PYTA-Pt(II) enhance the charge transfer and H 2 evolution. • TOF of Pd(II) or Pt(II) is prominently higher than that of common Pd and Pt metal. In artificial photocatalysis, sluggish kinetics of surface redox reactions and high charge recombination have been the barriers to photocatalytic conversion efficiency. Herein, metallosupramolecular complexes PYTA-Pd(II) and PYTA-Pt(II) were constructed by 1,2,3-triazopyridine derivatives (PYTA) coordinated Pt(II) and Pd(II). Originating from their planar conjugate structure and metal active center, PYTA-Pd(II) and PYTA-Pt(II) worked as molecular co-catalysts that can not only reduce the energy barrier of hydrogen evolution but also promote charge transfer. When g-C 3 N 4 (CN) is loaded with PYTA-Pd(II) or PYTA-Pt(II), its photocatalytic H 2 evolution reaction activity increased by 264 and 303 times, respectively. Moreover, the turnover frequency (TOF) of the Pd(II) in the CN/PYTA-Pd(II) is 25.94-fold than that of the Pd metal in the CN/Pd photocatalyst. And the TOF of Pt(II) in the CN/PYTA-Pt(II) photocatalyst is 9.37-fold than that of the Pt metal in the CN/Pt photocatalyst. These metallosupramolecular co-catalysts represent a new and highly effective approach to boost photocatalytic H 2 evolution and have provided fertile new ground for creating high-efficiency photosynthesis systems, increasing the utilization efficiency of noble-metal. [ABSTRACT FROM AUTHOR]

Formic acid is an appealing hydrogen storage material. In order to rapidly produce hydrogen from formic acid under relatively mild conditions, high-efficiency and stable photocatalytic systems are of great significance to prompt hydrogen (H2) evolution from formic acid. In this paper, an efficient and stable photocatalytic system (CdS/P/MoS2) for H2 production from formic acid is successfully constructed by elemental P doping of CdS nanorods combining with in situ photodeposition of MoS2. In this system, P doping reduces the band gap of CdS for enhanced light absorption, as well as promoting the separation of photogenerated charge carriers. More importantly, MoS2 nanoparticles decorated on P-doped CdS nanorods can play as noble-metal-free cocatalysts, which increase the light adsorption, facilitate the charge transfer and effectively accelerate the hydrogen evolution reaction. Consequently, the apparent quantum efficiency (AQE) of the designed CdS/P/MoS2 is up to 6.39% at 420 nm, while the H2 evolution rate is boosted to 68.89 mmol·g−1·h−1, which is 10 times higher than that of pristine CdS. This study could provide an alternative strategy for the development of competitive CdS-based photocatalysts as well as noble-metal-free photocatalytic systems toward efficient hydrogen production. [ABSTRACT FROM AUTHOR]

A metal complex (R-TAP-Pd(II)) constructed by chiral molecule R-TAP coordinated Pd(II) was used to modify g-C 3 N 4 to promote the separation efficiency of photogenerated carriers. Meanwhile, the R-TAP-Pd(II) acts as an activation site for proton reduction reaction, which enhances the photocatalytic H 2 evolution. [Display omitted] The photocatalytic H 2 production activity of polymer carbon nitride (g-C 3 N 4) is limited by the rapid recombination of photoelectron-hole pairs and slow surface reduction dynamic process. Here, a supramolecular complex (named R-TAP-Pd(II)) was fabricated via self-assembly of (R)-N-(1-phenylethyl)-4-(4-(pyridin-2-yl)-1H-1,2,3-triazol-1-yl)benzamide (R-TAP) with Pd(II) and used to modify g-C 3 N 4. In the R-TAP-Pd(II)@g-C 3 N 4 composite photocatalyst, the spin polarization of R-TAP-Pd(II) can promote charge transfer and inhibit photogenerated carrier recombination, as confirmed by spectral tests and photoelectrochemical performance tests. Electrochemical tests and in situ X-ray photoelectron spectroscopy (XPS) tests proved that the Pd(II) ion in the R-TAP-Pd(II) molecule can serve as active sites to accelerate H 2 production. The R-TAP-Pd(II)@g-C 3 N 4 presented a photocatalytic H 2 generation rate of 1085 μmol g−1 h−1 when exposed to visible light, which was a about 278-fold increase compared with g-C 3 N 4. This work finds a new approach to boost the photocatalytic efficiency of g-C 3 N 4 via supramolecular self-assembly. [ABSTRACT FROM AUTHOR]

• The Schottky connection between MoB 2 and g-C 3 N 4 allows for faster separation of photoexcited electron-hole pairs. • The addition of MoB 2 to g-C 3 N 4 improves its reduction ability, resulting in more efficient H 2 production. • The light absorption ability of g-C 3 N 4 is improved via modification with MoB 2. • MoB 2 @g-C 3 N 4 composite photocatalysis shows excellent photocatalytic hydrogen production activity. The g-C 3 N 4 material, which exhibits a sensitivity to visible light and has a band position that is appropriate for the photoreduction of H 2 , has garnered significant interest. However, the ability of g-C 3 N 4 to use light for photocatalysis is restricted due to its insufficient capacity to absorb light and its poor reaction kinetics on the surface. The researchers opted for the metallic MoB 2 to create a Schottky junction coupled with g-C 3 N 4. The incorporation of MoB 2 nanoparticles onto g-C 3 N 4 enhances its light absorption capacity and promotes the efficient separation and transfer of photogenerated charge. In addition, MoB 2 nanoparticles served as active sites to accelerate H 2 evolution. Compared to g-C 3 N 4 , the MoB 2 @g-C 3 N 4 composite exhibited a nearly 51-fold increase in H 2 production rate, indicating a significant improvement in photocatalytic activity. The present investigation demonstrated the potential of metallic MoB 2 as a modified material during a photocatalytic H 2 evolution reaction. [ABSTRACT FROM AUTHOR]

A noble-metal-free photocatalyst was successfully constructed by the integration of phosphorus doping and in situ loading Ni 2 P/Cu 3 P on g-C 3 N 4. Experimental investigations showed that the fast charge transfer, the accelerated kinetics of surface redox reaction, and the enhanced light absorption, were the critical factors for photocatalytic hydrogen evolution from water. [Display omitted] • Ni 2 P/Cu 3 P@P-C 3 N 4 was constructed by in situ loading Ni 2 P/Cu 3 P and P doping on g-C 3 N 4. • Ni 2 P/Cu 3 P@P-C 3 N 4 showed the fast charge transfer and redox reaction. • The photocatalytic H 2 evolution rate of Ni 2 P/Cu 3 P@P-C 3 N 4 is 201-fold than g-C 3 N 4. Research on the subject of photolysis focuses on the creation of effective non-precious metal co-catalysts. Graphitic carbon nitride (g-C 3 N 4) is a promising candidate for photocatalytic hydrogen generation from water. But its photocatalytic activity is limited by the slow redox reaction, high carrier recombination rate, and inadequate optical absorption. Incorporating in situ loading Ni 2 P/Cu 3 P and phosphorus doping on g-C 3 N 4 is effective in overcoming the drawbacks. Phosphorus doping reduces the band gap of g-C 3 N 4 for increased light absorption and improves the separation of photogenerated charge. Additionally, Ni 2 P/Cu 3 P heterojunctions anchored on P-doped g-C 3 N 4 (P-C 3 N 4) as non-noble co-catalysts boost light adsorption, enabling charge transfer and speeding the hydrogen evolution process. The resultant Ni 2 P/Cu 3 P@P-C 3 N 4 composite photocatalyst achieves an effective photocatalytic hydrogen evolution rate of 201 times greater than that of g-C 3 N 4 (12.9 μmol·h−1·g−1). This work is instructive to develop efficient g-C 3 N 4 -based photocatalysts for photocatalytic water splitting without the need for noble metals. [ABSTRACT FROM AUTHOR]