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It is important for water utilities to provide esthetically acceptable drinking water to the public, because our consumers always initially judge the quality of the tap water by its color, taste, and odor (T&O). Microorganisms in drinking water contribute largely to T&O production and drinking water distribution systems (DWDS) are known to harbor biofilms and microorganisms in bulk water, even in the presence of a disinfectant. These microbes include T&O-causing bacteria, fungi, and algae, which may lead to unwanted effects on the organoleptic quality of distributed water. Importantly, the understanding of types of these microbes and their T&O compound-producing mechanisms is needed to prevent T&O formation during drinking water distribution. Additionally, new disinfection strategies and operation methods of DWDS are also needed for better control of T&O problems in drinking water. This review covers: (1) the microbial species which can produce T&O compounds in DWDS; (2) typical T&O compounds in DWDS and their formation mechanisms by microorganisms; (3) several common factors in DWDS which can influence the growth and T&O generation of microbes; and (4) several strategies to control biofilm and T&O compound formation in DWDS. At the end of this review, recommendations were given based on the conclusion of this review.

MXene quantum dots (MQDs) offer wide applications owing to the abundant surface chemistry, tunable energy‐level structure, and unique properties. However, the application of MQDs in electrochemical energy conversion, including hydrogen evolution reaction (HER), remains to be realized, as it remains a challenge to precisely control the types of surface groups and tune the structure of energy levels in MQDs, owing to the high surface energy–induced strong agglomeration in post‐processing. Consequently, the determination of the exact catalytically active sites and processes involved in such an electrocatalysis is challenging because of the complexity of the synthetic process and reaction conditions. Herein, we demonstrated the spontaneous evolution of the surface groups of the Ti2CTx MQDs (x: the content of O atom), i.e., replacement of the ‐Cl functional groups by O‐terminated ones during the cathode reaction. This process resulted in a low Gibbs free energy (0.26 eV) in HER. Our steady Ti2COx/Cu2O/Cu foam systems exhibited a low overpotential of 175 mV at 10 mA cm−2 in 1 M aq. KOH, and excellent operational stability over 165 h at a constant current density of −10 mA cm−2.