Atomically Dispersed d10 s-block Au Boosts Photocatalytic 1e- Water Oxidation for Self-Cleaning, Sanitation and Safe Drinkable Water­­ (preprint)

Providing affordable safe drinking water and universal sanitation poses a grand challenge especially after the global COVID-19 pandemic. In this work, we developed atomically dispersed Au on potassium-incorporated polymeric carbon nitride (AuKPCN) that could simultaneously boost photocatalytic generation of ·OH and H2O2 with an apparent quantum efficiency over 90% at 400–420 nm. The introduction of potassium into the poly(heptazine imide) matrix formed strong K-N bonds, preventing Au from forming strong interactions with N. Instead, Au formed a bond with C, only having weak interactions with N on KPCN, which rendered Au with an oxidation number close to 0. The results of in-situ vibrational spectroscopy, isotopic experiments, transient absorption spectroscopy and time-dependent density functional theory (TDDFT) simulations revealed that the low-valent Au could append its 6s orbital into the band diagram of AuKPCN that formed a trapping level for generating highly localized holes under photoexcitation. These highly localized holes could boost the 1e− water oxidation reaction to form highly oxidative ·OH and simultaneously unbind the hydrogen atom in H2O molecule, which greatly promoted the hydrogenation process during the 2e− oxygen reduction reaction (ORR) to produce H2O2. The photogenerated ·OH on AuKPCN led to a more than 120-fold efficiency enhancement for visible-light-response superhydrophilicity as compared to that of the commercial TiO2. The onsite fixed-bed reactor under photo-illumination achieved a remarkable 132.5 LH2O m− 2 day− 1 water disinfection rate (lg6), which is about 30 times superior than the TiO2 photocatalytic advanced oxidation process in the most ideal case (< 4 LH2O m− 2 day− 1; lg4).

Integrating health behavior theories to predict COVID-19 vaccines uptake intent among the American public (preprint)

Wide uptake of coronavirus disease 2019 (COVID-19) vaccines is key to containing the ongoing pandemic. Integrating constructs from three prominent health behavior theories (HBT) including the extended parallel process model (EPPM), the health belief model (HBM) and the theory of planned behavior (TPB), the current study seeks to identify sociopsychological factors that influence American public’s COVID-19 vaccines uptake intent. An online survey was delivered to a national sample (N = 934) with demographic composition similar to the U.S. population. This study assessed the influences of risk perception and fear associated with COVID-19, beliefs about and attitudes toward COVID-19 vaccines, self-efficacy, social and psychological contexts, and demographic characteristics on people’s intention to get COVID-19 vaccines. Most respondents intended to get a COVID-19 vaccine once it is available. However, participants tended to underestimate their risks of contracting COVID-19, which may prevent them from getting vaccinated. Exposure to COVID-19 infections and deaths led to higher uptake intent via the mediation of fear. Concerns about the safety of COVID-19 vaccines negatively influenced vaccination intention, while perceived community benefits of the vaccines were positively associated with vaccination intention. Positive attitudes toward vaccines in general and recent vaccine history were also positively linked to COVID-19 vaccines uptake intent. This study attests the effectiveness of HBT constructs in predicting COVID-19 vaccines uptake intent. The results point to the importance of fostering confidence in vaccine safety in interventions seeking to promote COVID-19 vaccines uptake.