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It is an effective method to explore the full spectrum responsive photocatalysts for enhancing their photocatalytic activity. Herein, we have combined the upconversion phosphor with semiconductor to design the full‐spectrum light responsive photocatalyst. A facile approach has been developed for synthesis of NaYF4:Yb,Tm@TiO2 core‐shell structured composite. The morphologies, crystal phases, chemical compositions, optical performance, and photoelectric properties were characterized. Based on SEM and TEM observation, the formation mechanism of NaYF4:Yb,Tm@TiO2 composite was discussed in detail. The results of photodegradation experiment showed that 22% of Rhodamine B dye in the solution was photodegradated by NaYF4:Yb,Tm@TiO2 composite under NIR light irradiation within 150 min, suggesting that the NaYF4:Yb,Tm@TiO2 core‐shell structured composite displayed photocatalytic activity under NIR light irradiation. Furthermore, the photocatalytic ability of NaYF4:Yb,Tm@TiO2 is obvious superior to that of TiO2 under the full‐spectrum light irradiation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Zn x Cd 1-x S was firstly applied to photo-Fenton system as catalyst and co-catalyst. • The ZCS-3 photo-Fenton system exhibited satisfactory catalytic performance. • The photocatalysis of that system was synergized with co-catalysis. The exploration of new catalysts or co-catalysts to promoting the circulation efficiency between Fe3+ and Fe2+ in photo-Fenton system is of great significance for sewage treatment. Herein, metallic sulfides (Zn x Cd 1-x S) with different molar ratio of Zn/Cd were constructed by a facile solvothermal technology and applied to photo-Fenton system as both catalyst and co-catalyst for the first time. The catalytic activity of photo-Fenton systems could be enhanced by adding any as-prepared samples. Moreover, photo-Fenton system containing ZCS-3 (molar ratio of Zn:Cd = 3:7) presented the highest degradation rate for Rhodamine B (RhB, 93.5%), which showed significant improvement compared with that of photo-system without ZCS-3(43.7%). The excellent performance of this photo-Fenton system was mainly ascribed to the synergistic effect between photocatalytic and co-catalytic of ZCS-3. EPR and XPS results confirmed that the Zn2+ in the ZCS-3 would be reduced to Zn+ by the •O2–, which generated under visible light irradiation in photo-Fenton system. Thereby, more Zn+/Zn2+ exposed on the ZCS-3 surface during this photo-Fenton reaction, ensuring the acceleration of conversion between Fe2+ and Fe3+. The catalytic mechanism revealed that the formation of stable double recycles of Zn2+/Zn+ and Fe2+/Fe3+ in catalytic process displayed prominent enhancement for the catalytic properties of the photo-Fenton system. [ABSTRACT FROM AUTHOR]

[Display omitted] • CuS-Cu 9 S 8 micro-flower was applied to Fenton system as co-catalyst. • CuS-Cu 9 S 8 has positive influence on the degradation of organic pollutions. • Cu+/Cu2+ redox pairs in the CuS-Cu 9 S 8 accelerated the Fe2+/Fe3+ conversion cycle. The co-catalyst plays an important role for improving the catalysis efficiency in Fenton system. In this paper, a new co-catalyst, CuS-Cu 9 S 8 micro-flower was successfully prepared by a facilely hydrothermal method. The effect of co-catalysis for CuS-Cu 9 S 8 micro-flower was evaluated by degradation of Rhodamine B (RhB) in Fenton system, and the RhB solution could be degraded 90% in 15 min in the CuS-Cu 9 S 8 co-catalytic Fenton system under optimal condition, which is apparently better than that of the conventional Fenton system (59%). And EPR result shows that the unsaturated S atoms on the surface of CuS-Cu 9 S 8 can capture protons to form H 2 S and expose more Cu+/Cu2+ active sites on the surface of CuS-Cu 9 S 8 flower. The high co-catalytic activity of CuS-Cu 9 S 8 on pollutant degradation can be attributed to the acceleration for the rate-limiting Fe2+/Fe3+conversion by the exposed Cu+ /Cu2+ redox pairs. The cycle experiments show that CuS-Cu 9 S 8 has excellent chemical stability and reusability. [ABSTRACT FROM AUTHOR]

• The novel Yb3+/Tm3+ co-doped Ti 3 C 2 /Ag@Ag 3 VO 4 composite was fabricated by in-situ partially reduction-hydrothermal strategy. • The resultant Yb3+/Tm3+ co-doped Ti 3 C 2 /Ag@Ag 3 VO 4 composite exhibited enhanced photo-degradation performance under visible light irradiation. • The synthetic process and the corresponding photocatalytic mechanism was proposed and investigated detailedly. A novel Yb3+/Tm3+ co-doped Ti 3 C 2 /Ag/Ag 3 VO 4 composite with stable and robust photodegradation performance was synthesized by in-situ partially reduction along with hydrothermal strategy. In the composite, block-like Ag 3 VO 4 particles are self-assembled on the surface of 2D Ti 3 C 2 MXene accompanied by partial reduction of Ag+ to Ag0. Photodegradation results showed that the resulting Yb3+/Tm3+ co-doped Ti 3 C 2 /Ag/Ag 3 VO 4 composite with optimal Yb/Tm proportion (Y/T:0.3/0.005) presented a boosting photocatalytic performance for degradation of tetracycline (TC) and organic dyes under visible light irradiation. The removal efficiency was 97% for TC in 20 min, 96% for rhodamine B in 25 min, and 99% for methylene blue in 20 min, which was higher than that of Ag/Ag 3 VO 4 composite. As manifested by photoelectrochemical measurements, the enhanced photocatalytic performance of the Y/T:0.3/0.005 composite was attributed to the improved light absorption and excellent charge separation induced by the formation of intermediate energy states after co-doping Yb3+/Tm3+ ions. Meanwhile, the photocatalytic mechanism of the photocatalyst was also investigated through electron spin resonance (ESR) spectra and trapping experiments, which verified that the active species of h+ and ·O 2 − play the important role for photodegradation of tetracyline and organic dyes. [ABSTRACT FROM AUTHOR]

Ternary Ti 3 C 2 –OH/ln 2 S 3 /CdS composites with an efficient visible-light-driven photocatalytic performance have been prepared via a facile hydrothermal synthesis method. The photo-degradation experiments verified that Ti 3 C 2 –OH/ln 2 S 3 /CdS composite with a large surface area of 68.2 m2/g exhibited an enhanced photocatalytic activity and adsorption capacity towards Rhodamine B under visible light irradiation, which was higher than that of the naked CdS and ln 2 S 3 , respectively. Furthermore, Ti 3 C 2 –OH/ln 2 S 3 /CdS composite showed robust degradation efficiency for mixture dyes of RhB and Methyl Orange (MO), and its catalytic ability was superior to that of ternary GO/ln 2 S 3 /CdS composite. The trapping experiments for active species revealed that hole (h+) and •O 2 − species played a critical role in the removal of organic pollutants. In summary, the enhanced photocatalytic performance of Ti 3 C 2 –OH/ln 2 S 3 /CdS photocatalyst was derived from an excellent charge carrier separation and transfer of Ti 3 C 2 –OH MXene and the synergistic effect between CdS and ln 2 S 3 which resulting in strong visible light response. Image 1 • The Ti 3 C 2 –OH/In 2 S 3 /CdS composite was fabricated via a facile hydrothermal route. • The Ti 3 C 2 –OH/In 2 S 3 /CdS composite exhibited enhanced photo-degradation performance under visible light irradiation. • The photocatalytic mechanism of the Ti 3 C 2 –OH/In 2 S 3 /CdS composite has been investigated carefully. [ABSTRACT FROM AUTHOR]