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Graphical abstract Highlights • One-pot synthesis of noble-metal-free MoS 2 /CdS is time and energy-saving. • In-situ synthesized MoS 2 /CdS significantly retards charge recombination. • Optimized MoS 2 /CdS exhibits outstanding performance among similar catalytic systems. Abstract Semiconductor-based photocatalytic degradation of organic pollutant shows bright prospect and has potential to address the global environmental issues. But the low efficiency, currently, is still an obstacle, which stems from ultrafast charge recombination. In this manuscript, MoS 2 /CdS nanodots-on-nanorods heterostructures were successfully synthesized via a novel but facile one-pot solvothermal approach with less time and energy consumption. The in-situ synthesized MoS 2 /CdS heterostructures with intimate interface between MoS 2 and CdS facilitate photogenerated charge transportation and separation. Besides, the discrete distribution of MoS 2 nanodots on CdS nanorods offers a great many active sites for organic dye degradation. As a result, the optimized MoS 2 /CdS hybrid shows an excellent photodegradation performance of rhodamine B (RhB) with 99.11% of RhB decomposition in 45 min, which is the advanced among all the similar catalytic systems. Our findings will give inspiration for developing low-cost and efficient catalysts for photodegradation of organic pollutants. [ABSTRACT FROM AUTHOR]

We presented the first demonstration of a new structure KD*P crystal as electro-optic switch, in which the thermal depolarization loss was intrinsically reduced. The thermally induced birefringence and depolarization of both cylindrical and rectangular crystalline structure were simulated. The higher pulse energy or average power output was achieved in the diode pumped E-O Q-switched laser using a rectangular KD*P crystal. At the repetition rate of 100 Hz, the maximum average output power was 27.2 W at 145 A pump current, corresponding to the pulse energy was 272 mJ with pulse width of 65 ns and the beam quality of M 2 =20.4. Comparing the highest average power or corresponding single pulse energy, the laser with the rectangular KD*P crystal was two times of the laser with the traditional cylindrical KD*P crystal. [ABSTRACT FROM AUTHOR]

Designing efficient non-precious electrocatalysts to boost water splitting for green energy is a worthy and crucial objective, while it is still an enormous challenge. Herein, single-phase Ni5P4 ultrathin porous nanosheets grown on Ni foam constructed using the three-dimensional single-phase hierarchical nanoflower Ni5P4 (defined as 3D SHF-Ni5P4) were assembled via a simple hydrothermal and phosphating process in an enclosed space. Benefitting from the special structure and morphology of 3D hierarchical porous ultrathin nanosheets, as well as their increasing number of active sites, the 3D SHF-Ni5P4 exhibited outstanding performance with low overpotentials of 180 mV and 106 mV for achieving a current density of 10 mA cm−2 in 1 M KOH toward both the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER), and the Tafel slopes were 54 mV dec−1 and 79 mV dec−1, respectively. The overall water separation setup, using 3D SHF-Ni5P4 as both the cathode and anode in 1.0 M KOH, achieved a current density of 10 mA cm−2 at a low voltage of 1.47 V, which surpasses that of the commercial Pt C/NF‖‖RuO2/NF (1.52 V). This work highlights an achievable strategy for the controllable fabrication of a 3D single-phase hierarchical nanoflower Ni5P4 electrocatalyst, constructed with ultrathin porous nanosheets containing plenty of active sites. It provided new insights into developing cost-effective single-phase electrocatalysts towards green energy by water splitting. [ABSTRACT FROM AUTHOR]

In the work, we have focused on the surface variations of the LiNi 0.90 Co 0.04 Mn 0.03 Al 0.03 O 2 induced by the lithium ion conductor Li 0.34 La 0.56 TiO 3 and over-lithiated oxide Li 2 NiO 2 double coverings. The influence of various covering materials on particles morphology, crystal structure and electrochemical properties have been explored. It is found that the Li 0.34 La 0.56 TiO 3 firm layer could reduce the catalytic decomposition of electrolyte and further maintain the stable particles morphology and crystal structure of cathode after long-term cycling. In addition, the Li 2 NiO 2 served as the lithium supplement additive could compensate the irreversible active lithium ions loss during cycling and then relieve the cyclic capacity attenuation. Comparatively, the cathodes after Li 0.34 La 0.56 TiO 3 coating deliver the obvious enhanced rate capability, superior discharging capacity at low temperature and more stable cyclic performance than those of pristine LiNi 0.90 Co 0.04 Mn 0.03 Al 0.03 O 2. Besides, the Li 0.34 La 0.56 TiO 3 and Li 2 NiO 2 co-coated sample demonstrates the superior safety performance and cyclic stability when applied in the pouch battery in comparison with the pristine cathode. [Display omitted] • Li 0.34 La 0.56 TiO 3 and Li 2 NiO 2 co-covering is adopted to enhance LiNi 0.90 Co 0.04 Mn 0.03 Al 0.03 O 2. • Li 0.34 La 0.56 TiO 3 layer could maintain the morphology and structure stability. • Li 2 NiO 2 could compensate the irreversible active Li+ loss. • Li 0.34 La 0.56 TiO 3 and Li 2 NiO 2 co-coated cathode delivers the superior safety and cyclic stability. [ABSTRACT FROM AUTHOR]

The development of excellent photocatalysts for hydrogen evolution is of great significance to solving the global energy crisis. In this work, a novel 3D hierarchical CdS/NiAl-LDH photocatalyst was fabricated by a facile electrostatic assembly strategy, which was composed of 1D CdS nanorods and 3D flower-like NiAl-LDH microspheres. Under the visible irradiation, the CNA-20 hierarchical photocatalyst presents the optimum hydrogen evolution rate achieved to 3.24 mmol g−1 h−1, which is improved 6.23-fold in comparison with the pure CdS. Through the analysis of energy band structures and first-principles calculation, the type-Ⅱ charge transfer mechanism was proposed. Driven by the built-in electric field, as well as the effect of intimate interface contact of CdS and NiAl-LDH, the photogenerated charge could be achieved rapidly separate and migrate, which effectively promotes the H 2 evolution. This well-designed synergistic 1D/3D interface interaction and provides an economic approach to rationally developing metal-free photocatalysts for hydrogen production. [Display omitted] • A novel 3D hierarchical CdS/NiAl-LDH photocatalyst was fabricated by the electrostatic self-assembly strategy. • The CdS/NiAl-LDH photocatalyst displays excellent H 2 production activity and stability. • DFT calculations helped to explain the charge transfer at the heterojunction interface between CdS and NiAl. • A possible charge transfer mechanism during the photocatalytic H 2 evolution was proposed. [ABSTRACT FROM AUTHOR]

The utilization of Bi/Sn alloy-based materials has garnered significant interest as a promising avenue for the development of sodium-ion batteries and the achievement of electrocatalytic CO 2 reduction. This is due to their notable attributes of high theoretical specific capacity and low working potential, as well as their abundance and high catalytic activity. Nevertheless, the practical application potential of these alloys is restrained by their inadequate electrical conductivity without incorporating conductive carbon networks to improve the electrical conductivity of the composite material and consequential volumetric fluctuations, which ultimately lead to unsatisfactory cycle life and the depletion of active components. A single-atom Bi-coated Sn nanoparticle was synthesized utilizing metal-organic framework (MOF) compounds as precursors. The resulting composite exhibits the ability to mitigate volume changes that arise during charge and discharge processes, while also enhancing the catalytic activity of the system for CO 2 reduction through synergistic effects. Upon pyrolysis of the MOFs at elevated temperatures, a carbon matrix "protective layer" is formed to prevent the loss of active substances under conditions of electrode pulverization. This leads to improved cycle stability and coulomb efficiency of the battery. The ion permeation and gas diffusion are facilitated by the three-dimensional porous structures of composites. The conductive networks further improve the conductivity of materials, prevent the shedding of electrode material from electrodes, and facilitate electron transport. Consequently, the electrode demonstrates exceptional electrochemical performance, as evidenced by a high capacity of 510 mAh g−1 after 1000 cycles and a reversible capacity of 497 mAh g−1 after 500 cycles. Furthermore, the composite material demonstrates a notable degree of selectivity towards CO 2 reduction, as evidenced by a coulombic efficiency of 95.7% for HCOOH at a potential of −1.1 V but only a coulombic efficiency of 2.3% for H 2. Furthermore, the composite material exhibits commendable stability. The findings presented in this study offer valuable technical insights towards the attainment of carbon neutrality and carbon peaking. • A single-atom Bi-coated Sn nanoparticle was synthesized utilizing metal-organic framework compounds as precursors. • The composites exhibit superior sodium storage stability and electrocatalytic CO 2 reduction capability. • The composite demonstrates a coulombic efficiency (CE) of 95.7% for HCOOH at a potential of −1.1 V but only a CE of 2.3% for H 2. [ABSTRACT FROM AUTHOR]

The 1D Mn 0.47 Cd 0.53 S nanorods loaded with 0D CoWO 4 nanoparticles were prepared, in addition, a possible mechanism of the photocatalytic H 2 production activity was proposed. [Display omitted] • CoWO 4 Modified Mn 0.47 Cd 0.53 S was synthesized by simple hydrothermal process. • The CoWO 4 /Mn 0.47 Cd 0.53 S-25 can be used as a low cost catalyst for H 2 evolution. • The CoWO 4 /Mn 0.47 Cd 0.53 S-25 demonstrates excellent H 2 production activity and stability. To enhance the photocatalytic activity, loading proper semiconductor with high efficiency and low cost is one of the most valid approaches. Herein, various amounts of CoWO 4 as a novel metal-free material were loaded on Mn 0.47 Cd 0.53 S (MCS) nanorods for photocatalytic hydrogen production reaction. The CoWO 4 /Mn 0.47 Cd 0.53 S-25 (CW/MCS-25) exhibits the highest hydrogen production rate of 41.53 mmol·h−1·g−1 in the Na 2 S/Na 2 SO 3 system, which is about 2.68 times higher than that of pristine MCS. The Mapping and HRTEM reveals the deposited of CoWO 4 on the MCS. The detailed analyses of XPS, EIS, TRPL spectra and transient photocurrent responses indicate that CoWO 4 and MCS interacted closely and the photogenerated electrons of CoWO 4 can be transferred into MCS. In particular, the introduction of CoWO 4 can further transfer the photogenerated holes of MCS, thereby inhibiting the photocorrosion of MCS and improving photocatalytic activity. This work provides a reference for the exploration of noble metal-free composite material and shows great potential in the photocatalytic application. [ABSTRACT FROM AUTHOR]

Heterometallic cluster-organic frameworks with fascinating architectures and multi-functionality have the potential to be applied in various fields. However, in comparison with p–d, d–d, and d–f heterometallic cluster-organic frameworks, p–f heterometallic cluster-organic frameworks are far less explored even though they possess multiple merits. Herein, two novel isomorphic 4p–4f heterometallic cluster-organic frameworks based on high-nuclear [Ln11Ge12] (Ln = Pr, L1 and Nd, L2) second building units have been successfully synthesized via a hydrothermal approach by using bis(carboxyethylgermanium) sesquioxide (H2E2Ge2O3, E = –CH2CH2COO–). The [Ln11Ge12] cluster is constructed with two Ln-capped Ge6-rings sandwiching a gear-like [Ln9] unit. The as-prepared 4p–4f heterometallic [Ln11Ge12] cluster-organic frameworks possess two-dimensional (2D) layered structures. Moreover, the property study reveals the selective and sensitive luminescence sensing of Fe3+ with L1, exhibiting its promising application in environmental monitoring. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel dinuclear cobalt complex with definite structure was successfully synthesized and used as a cocatalyst in a photocatalyst H 2 production system. • This system exhibits an average H 2 evolution rate of 1045 μmol·h−1 within 8 h. • This system can work for 24 h with a TON of 16,400. Photocatalytic water splitting to produce hydrogen has gradually become a research hotspot in recent years, and molecular cocatalysts especially cobalt-based complexes as proton reduction cocatalysts have attracted wide attention due to their high activity and selectivity. In this study, CdS nanorods were employed as photosensitizers, and a novel dinuclear cobalt-bis(thiosemicarbazone) complex with definite structure was used as a cocatalyst to improve visible-light-driven hydrogen evolution. Under the optimum conditions, this noble metal-free system exhibited an average hydrogen evolution rate of 1045 μmol·h−1 in 8 h irradiation. This system could work for 24 h with a TON of 16,400, and the average apparent quantum yield of this system is ∼21% at 420 nm. On the basis of photoelectrochemical studies and electrochemical analysis, we proposed a possible mechanism for hydrogen production in this three-component system. [ABSTRACT FROM AUTHOR]