Qianqian Tang, Longshuai Zhang* and Jian-Ping Zou*
ABSTRACT
Advanced oxidation processes (AOPs), which generate reactive radicals like ·OH, ·SO4- and ·O2- for degradation and mineralization of organic wastes and contaminants, have been recognized as promising approaches in wastewater treatment. However, due to the stronger oxidability, these reactive radicals exhibit lower selectivity of degradation. Conversely, 1O2 is a weak oxidant that has strong electrophilicity and selectivity to remove electrons from electron-rich substances with long life, wide pH tolerance, and high selectivity. Currently, the commonly used method of producing 1O2 is the disproportionation of O2-. But the competitive reaction, the Haber-Weiss reaction (·O2- + H2O2 → ·OH + OH- + O2), significantly reduces the yield of 1O2. Thus, to activate PMS or PDS by effective catalysts for highly selective and efficient generation of 1O2 is necessary. Single-atom catalysts (SACs) with higher selectivity and efficiency in catalytic reactions are promising catalysts to approach that goal. In particular, the N-doped carbon supported SACs have exhibited significantly enhanced 1O2 generation selectivity from the activated PMS. However, the sparse and random distribution of N atoms, which act as coordination sites for metal atoms, causes the low metal loading and inhomogeneous local coordination environments, and further retards the high-efficient generation of 1O2.
Hongdong Li, Yue Pan, Jianping Lai*, Lei Wang* and Shouhua Feng
ABSTRACT
Sulfonate-Functionalized Polyoxovanadate-Based Metal-Organic Polyhedra for Enhanced Proton Conduction via the Synergy of Linker and Metal Cluster Vertex
Yu Zhang, Shan-Shan Liu, Bo Li, Hanqi You, Longxi Zhang, Zhenyi Zhang, Hong-Ying Zang*, Qi Zheng* and Weimin Xuan*
ABSTRACT
Shuwei Chai, Xiong Xiao, Yabei Li and Changhua An*
ABSTRACT
Guobing Mao, Heng Wu, Tianyang Qiu, Dingjie Bao, Longjie Lai, Wenguang Tu* and Qi Liu*
ABSTRACT
Hongnan Jia, Na Yao, Juan Zhu, Yujia Liu, Yunhao Lao, Hengjiang Cong* and Wei Luo*
ABSTRACT
Zhaoyang An, Hui Xue*, Jing Sun, Niankun Guo, Tianshan Song, Jiawen Sun, Yi-Ru Hao and Qin Wang*
ABSTRACT
Xingwang Yan, Bin Wang, Mengxia Ji, Qi Jiang, Gaopeng Liu, Pengjun Liu*, Sheng Yin, Huaming Li and Jiexiang Xia*
ABSTRACT
Designing simple, efficient, and environmentally friendly methods to construct high-efficient photocatalysts is an important strategy to promote the further development of the field of photocatalysis. Herein, flower-like carbon quantum dots (CQDs)/BiOBr composite photocatalysts have been prepared via in-situ synthesis by mechanical ball milling in the existence of ionic liquid. The CQDs/BiOBr composites exhibit higher photo-degradation performance for tetracycline (TC) than BiOBr monomer and the commercial Bi2O3 under visible light irradiation. For comparison, the different Br sources and synthetic methods are chosen to prepare BiOBr and CQDs/BiOBr composites. Photocatalysts prepared by ball milling and ionic liquid present significantly enhanced photocatalytic performance for removing TC. In addition, the introduction of CQDs could distinctly enhance the photocatalytic performances of pure BiOBr. The reason is that CQDs as electron acceptor effectively separate electrons and holes and inhibit their recombination. The intermediates during photocatalytic degradation were tested using liquid chromatography-mass spectrometry (LC-MS) and possible degradation pathways were given. During degradation, ?OH, O2?- and h+ were identified to be the main active species based on electron spin resonance (ESR) spectra and free radical trapping experiments. A possible mechanism of CQDs/BiOBr with enhanced photocatalytic performances was further proposed.
Ni(OH)2 Derived from NiS2 Induced by Reflux Playing Three Roles for Hydrogen/oxygen Evolution Reaction
Sheng-Jun Xu*, Ya-Nan Zhou, Guo-Ping Shen and Bin Dong*
ABSTRACT
Developing efficient and promising non-noble catalysts for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is vital but still a huge challenge for the clean energy system. Herein, we have integrated the active components for OER (Ni(OH)2) and HER (NiS2 and Ni(OH)2) into Ni(OH)2@NiS2 heterostructures by a facile reflux method. The in-situ formed Ni(OH)2 thin layer is coated on the surface of hollow NiS2 nanosphere. The uniform Ni(OH)2@NiS2 hollow sphere processes enlarge the electrochemically active specific surface area and enhance the intrinsic activity compared to NiS2 precursor, which affords a current density of 10 mA cm-2 at the overpotential of 309 mV and 100 mA cm-2 at 359 mV for OER. Meanwhile, Ni(OH)2@NiS2 can reach 10 mA cm-2 at 233 mV for HER, superior to pure NiS2. The enhanced performance can be attributed to the synergy between Ni(OH)2 and NiS2. Specifically, Ni(OH)2 has three functions for water splitting: providing active sites for hydrogen adsorption and hydroxyl group desorption and working as real OER active sites. Moreover, Ni(OH)2@NiS2 displays great stability for OER (50 h) and HER (30 h).
Synergism of 1D CdS/2D Modified Ti3C2Tx MXene Heterojunctions for Boosted Photocatalytic Hydrogen Production
Shi Cheng, Qianqian Xiong, Chengxiao Zhao* and Xiaofei Yang*
ABSTRACT