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A series of sub-nanoclusters (M/C-X, M = Pt, Pd, Ru. C = KB, CNT, rGO. X = O, N, S) synthesized by engineering anchor sites and reaction time. These materials have an excellent catalytic effect on the hydrogen evolution reaction.

The first synthesized porous Pd59W8Rh19Bi14 metallene combines OH adsorption effects, electronic effects and C–C bond cleavage site strategies to improve EOR performance. The metallene stable structure further accelerates the mass transfer rate.

Site-selective coupling of benzene and eosin Y into carbon-deficient g-C3N4 was performed with spatially separated charge carriers and enhanced photocatalytic performances.

As ammonia is an important chemical raw material, a lot of efforts have been made in the field of electrochemical nitrogen reduction (NRR) to promote artificial nitrogen fixation. At present, research on NRR is widely focused on improving the catalyst's adsorption and activation of N2. However, it has not yet been studied how to promote the desorption of NH3 by the catalyst to obtain continuous and stable catalytic activity. Herein, we synthesized Pd octahedrons and icosahedrons with similar sizes and studied the role of twins in NRR for the first time. At −0.2 V vs. RHE, the Pd icosahedron achieved a high NH3 yield and FE, which were 17.56 μg h−1 cm−2 (43.9 μg h−1 mgcat.−1) and 31.98%, respectively. After 200 h of electrolysis, the NH3 yield of Pd icosahedrons did not significantly decrease, which maintained excellent catalytic stability. Its performance is better than other catalysts that have been reported. In situ FTIR measurements and DFT calculation proved that due to the existence of the twin structure, the energy required for the potential-determining step and the NH3 desorption step of the Pd catalyst is greatly reduced. Accelerating the desorption of NH3 improves the utilization of active sites due to which the Pd icosahedron maintains continuous excellent catalytic activity. This provides a new direction for the design of catalysts to improve their NRR performance.

H2O2 has a wide range of uses as an oxidant and is also utilized as a high density and environmentally friendly fuel. In this study, crystalline g-C3N4 was modified with K+, Ni and N-doped carbon by thermal-polymerization of Ni2+-anchored and polyvinyl pyrrolidone-encapsulated melamine-cyanuric acid supramolecules, followed by re-calcination in a KCl–LiCl mixture. The obtained strip-like g-C3N4 nanocrystals exhibited high charge separation efficiency and good light absorption capability. Density-functional theory calculations confirmed that the orbital hybridization of Ni–N atoms enabled the formation of charge-transfer channels, which can capture electrons, achieve enhanced oxygen adsorption and reduction via a two-electron pathway. Under the synergistic effects of K+, Ni and N-doped carbon dopants and crystallinity, the obtained sample exhibited high photocatalytic H2O2 yields of 79.6 μM in O2-saturated pure water, which was 10-fold higher than the yield using pristine g-C3N4. This work provides a novel design for production of highly efficient photocatalysts for H2O2 production.

Solar-driven photocatalytic water-splitting for H2 production holds great promise to alleviate the growing energy and environmental crisis. Nevertheless, it is still challenging up to now to develop noble-metal-free photocatalysts which are efficient for the H2 evolution reaction (HER). In this work, based on the ion-exchange and alloying reactions between Zn and Cd ions in liquids, a template-assisted ion-exchange strategy combined with subsequent electrostatic assembly process was employed to prepare uniform ZnS@CdS@Cd0.5Zn0.5S-MoS2 hollow nanospheres for the first time. Under visible-light irradiation (λ > 420 nm), the ZnS@CdS@Cd0.5Zn0.5S-MoS2 hybrid exhibits an optimal HER activity of 50.65 mmol h−1 g−1, which is 20 times more than that of its Pt-decorated ZnS@CdS@Cd0.5Zn0.5S counterpart and superior to that of most CdS-based photocatalysts ever reported. Moreover, the ZnS@CdS@Cd0.5Zn0.5S-MoS2 hybrid exhibits good stability for the long-term HER. The outstanding HER capability of ZnS@CdS@Cd0.5Zn0.5S-MoS2 could be attributed to the dramatically facilitated separation of charge carriers, abundant active sites from the defect-rich 1T/2H MoS2 few-layered nanosheets, and enhanced light-harvesting of the hollow nanostructure. The findings indicated here could benefit the exploitation of high-performance photocatalysts for promising solar-to-fuel applications.

The electrochemical N2 reduction reaction (NRR) under ambient conditions is highly attractive. However, it is still a challenge to achieve a high NH3 yield rate at low overpotential. Herein, we report RuO2 nanoparticles with different degrees of surface selenation, which show excellent NRR performance at low overpotential. The NH3 yield rate and FE of RuO2–Se0.18/C reach 12.97 μg h−1 cm−2 and 26.01% at −0.1 V vs. RHE, respectively, which is the highest NH3 yield rate reported at low overpotential. The RuO2–Se0.18/C catalyst also shows excellent stability. The related NH3 yield rate stays pretty constant after 50 h of electrolysis. The density functional theory (DFT) calculations show multiple promoted-synergism of surface selenation on the RuO2 catalyst. First, optimized surface selenization could drive the adsorption of N2 on RuO2 sites. Second, surface hydrogenation promoted by surface selenization can suppress the hydrogen evolution reaction (HER, competitive reaction), enabling high NRR performance at low potential. Third, optimizing the surface selenization on RuO2 can promote N2 activation (*N2 → *NNH). Fourth, surface selenization can promote NH3 desorption (the rate-limiting step).

Both an excess and shortage of iron(III), away from normal permissible limits, can induce serious disorders, therefore its detection is significant, but still remains a challenge. Luminescent metal–organic frameworks (LMOFs) are a class of attractive materials for the detection of Fe3+ ions. However, improvement in their hydrolytic stability, speed, sensitivity, and selectivity of function is the key to the advanced application of LMOFs in an aqueous environment. Herein, two hydrostable LMOFs, Zn-DTA and Cd-DTA, based on the π-conjugated aromatic ligand 2,5-di(1H-imidazol-1-yl)terephthalic acid (H2DTA), were selected as highly efficient sensors for the rapid, sensitive and selective detection of Fe3+ in aqueous solutions. On the basis of the rigid structure and multiple coordination sites of the H2DTA ligand, Zn-DTA and Cd-DTA possess brilliant stability and excellent fluorescence emission. Both of them exhibit high selectivity (Ksv = 8400 and 6420 M−1) and high sensitivity (0.82 and 1.07 μM) for the rapid detection (less than 30 s) of small quantities of Fe3+ (0.2 mg mL−1) in water. It is worth noting that the compounds not only remain stable in the water for a long time but also maintain structural integrity at high temperatures. To the best of our knowledge, Zn-DTA and Cd-DTA, as two exceptionally stable MOF chemosensors used for the selective detection of Fe3+, show very rare behavior compared to the reported Zn/Cd-MOFs. The quenching mechanism for such a high selectivity can be mainly explained by the competition between the absorption of Fe3+ and the excitation of the compounds. Moreover, the introduced carboxyl O atoms of Zn-DTA additionally donate their lone-pair electrons to the Fe3+ ions, leading to enhanced detection ability. Our work reveals the enormous potential of LMOFs as an appealing platform upon which to construct sensing materials.

Correction for ‘Designed synthesis of unique ZnS@CdS@Cd0.5Zn0.5S-MoS2 hollow nanospheres for efficient visible-light-driven H2 evolution’ by Bowen Sun et al., CrystEngComm, 2020, 22, 2743–2755, DOI: 10.1039/D0CE00064G.

An acrylate monomer and diacrylate crosslinker containing a spacer of undecylene were synthesized and crosslinked liquid-crystalline polymer films with different crosslinking densities were prepared by photopolymerization of mixtures of the monomer and the crosslinker. Due to the relatively long spacer, distinct bending behavior was observed in the film with a low crosslinking density: when the temperature was lower than 90 °C, the film first bent away from the light source and then towards it upon the irradiation of UV light. As the temperature was raised above 90 °C, the film bent directly towards the light source. X-ray diffraction was used to probe the phase structures of the film at different temperatures and a plausible mechanism was presented to explain the distinct phenomenon. In addition, when the crosslinking density was increased, all the films bent directly towards the light source with faster speed, which is related to their modulus and order parameters.