As
a spontaneous renewable energy-based technology, with an astonishing
ability to destroy recalcitrant organic pollutants under ambient conditions,
solar-driven heterogeneous photocatalysis has sparked immense interest
over the past decade. However, creating photocatalysts with astounding
visible-light harnessing capacity and undemanding recuperation persists
as a significant hurdle to the widespread exploitation of photocatalysis
in water treatment. Herein, we propose a potentially nontoxic, robust,
durable, and self-supporting photocatalyst, based on the in situ growth
of few-layer (FL) WS2 nanosheets on the interpenetrating
channels of nitrogen (N)-doped graphene aerogel (henceforth denoted
as “WNGA”). Constructed through a mild hydrothermal
processing scheme, WNGA shows self-floating capability, exceptional
mechanical resilience, and remarkable solar absorption in the visible
range. In addition, the coexistence of pyridinic N species and FL-WS2 clusters synergistically provides surplus active sites for
catalytic reactions. Besides, the interconnected conductive networks
of WNGA coherently upregulate charge separation and transfer in 3D.
As a result of these beneficial attributes, WNGA presents prominent
photocatalytic activity and excellent recycling stability. For instance,
through a combination of adsorption and partial oxidation, WNGA can
dissociate up to 93% caffeine, the most widely consumed psychoactive
substance, into innocuous products over multiple cycles. As a figure-of-merit
for the commercial potential of WNGA, we also demonstrate the photocatalytic
degradation of caffeine in four different real matrixes, viz., tap
water, pond water, municipal wastewater, and hospital wastewater.
The exceptional photocatalytic properties, improved durability, and
facile retrieval opportunities validate the application potential
of WNGA to eliminate psychoactive substances in aqueous environments.