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Converting lignin, a key sustainable biopolymer, into valuable oxygen-containing compounds is a significant challenge. To address such a challenge, photocatalytic self-transfer hydrogenolysis strategy is employed utilizing a CdS(x%)/TiO 2 heterojunction photocatalyst, with minimal CdS loading on TiO 2. The CdS(3 %)/TiO 2 catalyst, under blue light, dehydrogenates HC α –OH groups, transferring hydrogen to C β –O bonds, cleaving β-O-4 ether bonds in lignin model compounds yielding over 95 % phenols and acetophenones. It utilizes glyceryl moieties as a hydrogen source, yielding ∼ 24 % of diverse lignin monomer derivatives from teak lignin. Improved charge separation in the CdS(3 %)/TiO 2 catalyst is revealed by electrochemical and spectral analyses and exhibits delayed charge carrier recombination. Scavenging studies confirm a type II charge transfer mechanism and support visible-light-driven lignin fragmentation. The present photocatalytic process offers a promising, cost-effective approach for converting lignin into valuable aromatic compounds, advancing renewable biomass-derived chemicals. [Display omitted] • CdS/TiO 2 type-II heterojunction facilitated efficient charge separation. • CdS(3%)/TiO 2 afforded renewable chemicals from lignin model compounds. • Additive-free hydrogenolysis was achieved under mild photocatalytic conditions. • CdS(3%)/TiO 2 showed exceptional photocatalytic stability and reusability. • High monomer yield (24%) and excellent activity were achieved with native lignin. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • In this work, we represents the first attempt on combining polyoxotantalate with metal sulfide via simple hydrothermal method to get a new-type Na 8 Ta 6 O 19 /Cd 0.7 Zn 0.3 S composite photocatalysts for visible-light-driven H 2 production from water splitting. • The composite photocatalyst of Na 8 Ta 6 O 19 /Cd 0.7 Zn 0.3 S has excellent visible-light-driven hydrogen evolution performance with good stability. • The achievement provides a new strategy to develop highly efficient and new-type photocatalysts for the sustainable utilization of solar energy. Abstract Polyoxometalates have been emerged in the field of photocatalytic hydrogen evolution reaction (HER) with attempt to get efficient, inexpensive, recyclable, and environmentally-benign photocatalysts. Here, it demonstrated that the combination of polyoxotantalates with metal sulfides can form none-noble-metal binary composite photocatalysts for efficient water splitting with visible-light. With the strategy, the first series of noble-metal-free composite photocatalysts based on the combination of hexatantalate Na 8 Ta 6 O 19 and metal sulfide Cd x Zn (1-x) S have been prepared and used as a heterogeneous photocatalyst. The Na 8 Ta 6 O 19 /Cd x Zn (1-x) S exhibits efficient hydrogen production activity, even without any cocatalysts. The maximum H 2 -evolution rate reaches 43.05 mmol h−1 g-1 (based on 10 mg catalyst) with the apparent quantum yield of 37% at 420 nm, which is the highest value ever reported so far for polyoxometalate-based photocatalysts to our knowledge. The achievement provides a new strategy to develop highly efficient and new-type photocatalysts for the sustainable utilization of solar energy by merging polyoxotantalate chemistry with photoredox catalysis. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A novel Ti 3 C 2 (TiO 2)@CdS/MoS 2 composite photocatalyst system was fabricated. • The band type of II junction and Z-scheme are organically combined. • The regulation of charge separation and transfer direction is realized successfully. • A high H 2 yield rate of 344.74 μmol h−1 g−1 can be reached in pure water. Abstract Spontaneous photocatalytic H 2 evolution from solar-driven water splitting is highly attractive for converting abundant solar energy to valuable fuel. Regulation of the direction of photocarriers separation and transport is an important factor influencing solar energy conversion efficiency. Here, structural design and energy band engineering are employed to design and construct a novel Ti 3 C 2 (TiO 2)@CdS/MoS 2 composite photocatalyst. The transfer direction of photogenerated electrons and holes is achieved via rational conjunction of Ti 3 C 2 and MoS 2. This well designed photocatalytic system possesses remarkable H 2 evolution rate (8.47 mmol h−1 g−1) and excellent photocatalytic stability. Furthermore, a high H 2 yield rate of 344.74 μmol h−1 g−1 can be reached in pure water without any electron sacrificial agents. Through combination with the scope of a type II junction between CdS and MoS 2 , the new Z-scheme between CdS and TiO 2 transformed from Ti 3 C 2 sets up a multi-step separation of electron-hole pairs. This process prolongs the lifetime of photogenerated electrons and makes them reach the active sites to initiate an efficient photocatalytic redox reaction. This work demonstrates that the design philosophy of selectively controlling the transfer direction of electrons and holes has promising applications in solar energyutilisation. [ABSTRACT FROM AUTHOR]

In this study, Pt@Cu 2 O/WO 3 composite photocatalyst was constructed via coupling Cu 2 O onto the edged (200) and (020) facets of square-like WO 3 nanoplates and followed by photodeposition of Pt onto Cu 2 O. The remarkably enhanced photocatalytic water oxidation activity over such assembled Pt@Cu 2 O/WO 3 composite photocatalyst was observed. The superior photocatalytic performance can be attributed to intrinsic nature of charge separation between different facets of square-like WO 3 , highly efficient WO 3 -to-Cu 2 O electron transfer occurring at the intimate contact interface between WO 3 and Cu 2 O, and Pt as reduction cocatalyst. This work will provide new deep insights into the design of crystal-based Z-scheme heterostructure photocatalysts by facet-preferentially coupling one semiconductor with another. [ABSTRACT FROM AUTHOR]

A novel composite with special structure and excellent performance, 5,10,15,20-tetrakis(4-hydroxyphenyl) porphyrin (THPP) coated Cu 2 O nanoparticle (Cu 2 O/THPP), was facilely prepared by a simple method. UV–vis spectra, FTIR and fluorescence spectra were used to explore the interaction mechanism between THPP molecule and Cu 2 O nanoparticle. The results demonstrated that the center of the THPP macrocycle could coordinate with Cu 2 O, besides hydrogen bond and/or electrostatic interaction between peripheries of THPP macrocycle and Cu 2 O. Furthermore, photocatalytic hydrogen evolution performance of the composite was investigated. The composite displayed more excellent performance for hydrogen evolution than that of pure THPP, pure Cu 2 O or 5,10,15,20-tetraphenylporphyrin (TPP) coated Cu 2 O nanoparticle (Cu 2 O/TPP). By means of fluorescence spectra, electrochemical impedance spectra and photoelectronic performance measurement, the mechanism of electron transfer in the composite was explored. The results showed that the strong synergetic interaction caused by the special combination mode between THPP and Cu 2 O can quicken the transfer of photo-generated electrons, and was very favorable to improve the performance of the Cu 2 O/THPP composite. [ABSTRACT FROM AUTHOR]

Highlights: [•] g-C3N4-WO3 photocatalysts with different main parts of C3N4 or WO3 were prepared. [•] The band–band transfer for g-C3N4/WO3 and the Z-scheme for WO3/g-C3N4 were proposed. [•] The activity of g-C3N4/WO3 is not obviously increased compared with pure WO3. [•] The activity of WO3/g-C3N4 is increased greatly compared with pure g-C3N4. [ABSTRACT FROM AUTHOR]

• A new photocatalyst TiO 2 @amylose/polyiodide/HEC was designed for the first time. • The photocatalyst possessed tunable and self-indicating delayed onset of performance. • Amylose/polyiodide contributed to stable stage and self-color-changing property. • HEC contributed to active stage's start occurring simultaneously with color changing. • A new photocatalyst for the first time for ideal photodegradable plastic development. The photocatalyst can be used as additives to plastic to increase the degradability of plastic products. However, the performance of photocatalyst cannot be delayed resulting in the unstable performance of plastic products during their usage. Even though when the delay can be realized, there is no color changing to indicate whether the performance starts or not. This hinders the industrial application of photocatalytic technology in plastic degradation. In this study, a new type of composite photocatalyst, TiO 2 @amylose/polyiodide/hydroxyethyl cellulose (T@AIH), is elaborately designed with self-indicating delayed onset of performance. T@AIH is prepared via the wet chemistry method. The periods before and after onset are named stable stage and active stage, respectively. The T@AIH is blue at stable stage, and the color changes to white when the photocatalytic performance of T@AIH starts. The length for the stable stage and reaction rate for the active stage are tunable. The properties of T@AIH at different stages are characterized. The results suggest that efficient I 3 −/I 5 − interconversion of polyiodide in amylose helical pitch plays a key role in electron-hole recombination, resulting in the stable stage. High diffusivity of polyiodide in HEC plays a crucial role in initiating the active stage and making it happen simultaneously with color changing. The performance of sample T@A 0.1 IH on low density polyethylene (LDPE) degradation is tested. This study proposes a new photocatalyst to increase the degradability of plastic in a self-indicating and delayed-onset way for the first time. [ABSTRACT FROM AUTHOR]