Size and shape regulated synthesis of silver nanocapsules for highly selective and sensitive ultralow bivalent copper ion sensor application

Abstract

The development of highly robust, quantitative, sensitive and naked eye colorimetric sensing of bivalent copper ions using bio-inspired synthesis of size and shape controlled silver nanocapsules (AgNCs) is reported herein. By carefully adjusting the reaction conditions, size and shape control over the resulting AgNCs can be realized, with a regulated size (10 nm) and shape (capsules). Such facile, one-pot and eco-friendly synthesized AgNCs with controlled size and shape sense selectively and sensitively the Cu²⁺ ion in industrial effluents with an ultralow detection limit of 2.6 × 10⁻⁹ mol L⁻¹. The formation and sensing mechanism of the AgNCs are demonstrated and discussed. The proposed method was successfully utilized for the determination of Cu²⁺ in different water samples.