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[Display omitted] It is challenging to develop high-efficient and stable nonprecious metal-based electrocatalyst for oxygen evolution reaction (OER) in acid for proton exchange membrane (PEM) water splitting. Herein, P atoms were introduced into the lattice of spinel Co 3 O 4 (P-Co 3 O 4) to replace with octahedral coordinated Co3+ via a hydrothermal process following a thermal treatment. The formation of PO 6 geometric configuration unit in Co 3 O 4 can trigger electron rearrangement around Co ions, which resulted in the high-active Co2+ site on the surface, significantly decreasing the energy barrier of rate-determining step for OER. Moreover, the weaker covalency of the Co 3d-O 2p bond and higher formation energy of oxygen vacancy around Co2+ in P-Co 3 O 4 inhibited the participation of lattice oxygen during OER process, enabling that P-Co 3 O 4 can work stably in acidic media. The obtained P-Co 3 O 4 afforded satisfying stability over 30 h in a PEM electrolysis device with an overpotential of 400 mV@10 mA/cm2 in 0.1 M HClO 4. [ABSTRACT FROM AUTHOR]

It is an effective approach to regulate the structure of photocatalysts by introducing the heteroatoms into the lattice for extended light absorption and enhanced charge separation. In this work, the P atoms were introduced to substitute the corner C atoms of g-C 3 N 4 by calcinating the melamine-phytic acid derived supramolecular with high-density phosphate groups, which is synthesized by hydrothermal method. The intermediate state produced by the introduction of P atoms leads to the enhanced light absorption of P–CN (7.2g-IP6) with a negative shifted conduction band position, which benefits the photocatalytic hydrogen reaction kinetically. Moreover, the electron transferred from P atom to the surrounding N atoms results in the positively charged P center, which could act as Lewis acid site. Such formed Lewis acid site at positively charged P center together with the Lewis base sites, such as amine or imine groups in P–CN, makes it easier to separate photogenerated charges, thus enabling the P–CN (7.2g-IP6) to exhibit an enhanced photocatalytic hydrogen rate of 2.743 mmol·g−1·h−1, which is about 6.77 times that of pristine g-C 3 N 4 (0.405 mmol·g−1·h−1). This work provides an alternative approach to regulating the structure of photocatalysts. • Melamine-Phytic Acid Derived Supramolecular (MP) was obtained by hydrothermal method. • P atoms was in situ introduced into g-C 3 N 4 by calcinating the MP precursor. • The P doped g-C 3 N 4 showed extended absorption and enhanced charge separation. • The P doped g-C 3 N 4 exhibited superior photocatalytic performance than pristine CN. [ABSTRACT FROM AUTHOR]

It is a great challenge to design active and durable oxygen evolution reaction (OER) electrocatalysts for proton exchange membrane (PEM) electrolyzer due to the high dissolution of electrocatalysts in acidic solution. Herein, the Nd‐doped RuO2 (Nd0.1RuOx) is developed for enhanced oxygen evolution in 0.5 m H2SO4 solution with an overpotential of 211 mV to achieve 10 mA cm−2. The theoretical calculation reveals that the improved activity of Nd0.1RuOx is due to the moderate decrease of d‐band center energy, which balances the adsorption and desorption of oxygen intermediates. Moreover, the formation of more high valence state Ru4+ in Nd0.1RuOx is beneficial to the chemical stability of Ru species during the OER process, indicating that the introduction of Nd can effectively suppress the dissolution of Ru in acidic electrolytes. In addition, the PEM electrolyzer using Nd0.1RuOx/CC as the anode can be operated at 10 mA cm−2 stably for 50 h. This study sheds new light on the design of the OER catalysts in acid by engineering the electronic structure of RuO2. [ABSTRACT FROM AUTHOR]

It is of great importance to promote charge separation in photocatalysts for enhanced photocatalytic activity under visible light irradiation. In this work, a type-II heterostructured photocatalyst was constructed by compositing phosphorus-doped g-C3N4 (P-CN) and Rh-doped SrTiO3 (Rh-STO) via a thermal calcination treatment. A series of characterizations were conducted to investigate the structure of heterostructured P-CN/Rh-STO. It was found that Rh-STO interacted with in situ generated P atoms from the decomposition of P-CN during the calcination process, thus leading to the formation of heterojunction of P-CN/Rh-STO. Compared with the single component, i.e., P-CN or Rh-STO, the obtained P-CN/Rh-STO showed superior photocatalytic activity to that of both P-CN and Rh-STO due to the effective charge separation across the heterojunction between P-CN and Rh-STO. [ABSTRACT FROM AUTHOR]

Photocatalytic hydrogen production has been considered a promising approach to obtain green hydrogen energy. Crystalline porous materials have arisen as key photocatalysts for efficient hydrogen production. Here, we report a strategy to in situ photodeposit platinum clusters as cocatalyst on a covalent organic framework, which makes it an efficient photocatalyst for light-driven hydrogen evolution. Periodically dispersed adsorption sites of platinum species are constructed by introducing adjacent hydroxyl group and imine-N in the region of the covalent organic framework structural unit where photogenerated electrons converge, leading to the in situ reduction of the adsorbed platinum species into metal clusters by photogenerated electrons. The widespread platinum clusters on the covalent organic framework expose large active surface and greatly facilitate the electron transfer, finally contributing to a high photocatalytic hydrogen evolution rate of 42432 μmol g−1 h−1 at 1 wt% platinum loading. This work provides a direction for structural design on covalent organic frameworks to precisely manipulate cocatalyst morphologies and positions at the atomic level for developing efficient photocatalysts. Porous covalent organic frameworks have arisen as tunable photocatalysts for H2 production. Here, authors report frameworks engineered with co-catalyst binding sites to improve photocatalytic H2 evolution performances. [ABSTRACT FROM AUTHOR]

Ce-doped NiO catalyst supported on MoO₂ nanorods (Ce-NiO@MoO₂) was constructed as a high-performance oxygen evolution reaction (OER) electrocatalyst. The introduction of Ce induced the formation of nanoflower-like NiO on the MoO₂ nanorod substrate. Ce doping not only created numerous unsaturated Ni coordination sites with higher oxidation states, serving as active sites, but also strengthened the adsorption of oxygen intermediates by upshifting the Ni 3d band center, thereby reducing the energy barrier of the rate-determining OH* → O* step. Consequently, the Ce-NiO@MoO₂ catalyst exhibited remarkable OER activity, with a low overpotential of 313 mV and outstanding 200-hour stability at 1000 mA cm⁻², which is attributed to unsaturated Ni active sites and promoted charge and mass transfer facilitated by the unique hierarchical structure. These findings highlight the crucial role of Ce doping in improving electrocatalytic performance and offer insights into developing efficient and cost-effective catalysts for large-scale hydrogen production via water electrolysis. [Display omitted] • Ce-NiO@MoO 2 showed excellent OER activity with a low overpotential of 313 mV and outstanding 200-hour stability at 1000 mA cm−2. • Ce doping created numerous unsaturated Ni sites with high OER activity and facilitated Ni2+ to Ni3+ transition. • Ce doping and oxygen vacancies strengthened the adsorption of oxygen intermediates by upshifting the Ni 3d band center. • The hierarchical core-shell structure and low RDS energy barrier synergistically enhanced OER activity at 1000 mA cm−2. [ABSTRACT FROM AUTHOR]

• Ce-doped Ni(OH) x /Cu(OH) 2 was construct for efficient OER. • Ce-doped Ni(OH) x /Cu(OH) 2 required an overpotential of 225 mV to reach 10 mA cm−2. • Ce-doped Ni(OH) x /Cu(OH) 2 can work stably for 50 at 100 mA cm−2. It is urgent to develop highly efficient anode materials for electrocatalytic oxygen evolution reactions due to their sluggish kinetics. In this work, Ce-doped amorphous Ni(OH) x was constructed on Cu(OH) 2 nanorods via the simple electrodeposition method. It was demonstrated that the Ce dopant resulted in the charge transfer from Ni to O, leading to the Ni3+ with a higher valence state, and thus functioning as active sites with more intrinsic activity. Moreover, the Ce dopant could also reduce the charge transfer resistance, leading to faster charge transport during the OER process. The obtained sample exhibited excellent OER performance with an overpotential of 225 mV at 10 mA cm−2 and stable operation at 100 mA cm−2 for 50 h. [ABSTRACT FROM AUTHOR]

• Triphenylphosphine (PPh3) was used for the phosphorization of g-C 3 N 4. • g-C 3 N 4 (PPh3) showed extended light absorption and promoted charge separation. • g-C 3 N 4 (PPh3) exhibited higher photocatalytic activity than g-C 3 N 4. It is an effective strategy to regulate the structure of photocatalysts for enhanced photocatalytic hydrogen evolution. In this work, a facile method was developed to introduce P atoms into g-C 3 N 4 via the thermal calcination treatment. In contrast to pristine g-C 3 N 4 , the obtained P-CN(PPh3) exhibited a negative shift of conduction band edge with enhanced light absorption after the introduction of P atoms into g-C 3 N 4 , thus benefiting the photocatalytic hydrogen evolution. Moreover, the introduction of P element in g-C 3 N 4 can also improve the charge separation during the photocatalytic hydrogen reaction, significantly accelerating the photocatalytic hydrogen production rate of P-CN(PPh3). [ABSTRACT FROM AUTHOR]